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This month, host Bill McGeeney is joined by astronomer, historian, author, science communicator, and dark-sky consultant, John Barentine of the Dark Sky Consulting LLC and Conservationist, Kaitlyn Evans. Learn more at LightPollutionNews.com.
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What did you think of this Episode? Text Us!
This month, host Bill McGeeney is joined by astronomer, historian, author, science communicator, and dark-sky consultant, John Barentine of the Dark Sky Consulting LLC and Conservationist, Kaitlyn Evans. Learn more at LightPollutionNews.com.
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Light pollution news 6. Unpacking the Lightplicks. Boy oh boy, what a show we have for you today. John Barrington of Dark Sky Consulting joins us, along with everyone's favorite bird or conservationist, caitlin Evans. This month we ask Texas, is 7 enough? Leave some dark sky reserves for the rest of us, texas? We learn that birds are not only remarkable meteorologists, but they have on-time departure numbers that will make American Airlines blush. And do you want to take a mini course on light pollution? Do you have it in you, light pollution 101? if you will, all that and more on this month's Light Pollution News, get ready for a new LPN coming your way right now.
Bill M:Welcome all to another Light Pollution News, the place you hear about all the news related to light pollution. As a reminder, you can read all these articles, learn lighting tips and more by visiting our website at light pollution newscom. The article listing for this show and for all shows can also be found at our Reddit r slash light pollution news And big news we now have an Instagram account. You can join us over at instagram at light pollution news. I'm your host, bill McGeady, and today I'm very excited to have with me science communicator. Remember the American Astronomical Society, the International Astronomical Society, any Royal Astronomical Society, john Barantine, how are you doing?
John B:I'm doing great, bill. How are you today?
Bill M:Doing alright, no big frustrations early on. I think we're doing great. And over here, next to John, i have a bird fanatic, caitlin Evans. You recall her from episodes two and three. Caitlin, you seen any good birds lately?
Kaitlyn E:Yeah, i saw my first-ever Canada warbler this week, so that was pretty exciting.
Bill M:Yeah. So what's the deal about Canada warbler? Why is that exciting?
Kaitlyn E:I mean, they're just migrants that come through the Philadelphia area so they don't breed here, so it's a little bit more rare of a sighting. They're a pretty magnificent looking warbler. They have like a blue gray back and a yellow front with like a black speckled necklace. They're pretty spectacular.
Bill M:Okay, it doesn't look like every other warbler, it's not just yellow.
Kaitlyn E:No, it looks a little different.
Bill M:Okay, John, do you have any experience chasing after warblers?
John B:Not warblers, but we've got some interesting birds down here. We're just winding up cardinal season, so our Arizona cardinals are out in full force and all of our migrants are leaving town because it will be blazing hot very soon.
Bill M:Oh yeah, no doubt.
Kaitlyn E:Doesn't sound like a bad idea, are?
John B:they just for animals or people?
Bill M:Well, today we start out with a humble admission. This one comes from Dana Millbank of the Washington Post. I was busted by the light police and they have a point. Dana Millbank purchased a home in Soon-A-Be, not-so-rural Virginia. At night he kept the formerly vacant lot lit to a degree that spurned one commentator to call it a spaceship lighting. Millbank recaps being visited by the light police. At first he was taken back, but later he not only was able to appreciate their efforts, he also ended up converting his blinding always-on light the white floodlights, over two nights.
Bill M:Warm 2700 Kelvin motion-sensing light. A per ruskin-heartly, the executive director of the International Dark Sky Association. For 4.5 billion years there was no artificial light at night. It's really only the last five human generations that we transform that. It's one of the most profound transformations of our environment. Many of you may recall an earlier story, way back in a hormone of darkness episode, showcasing concerns by local residents prior to a 760 housing development now 761 housing development. That included a town center and it was moving into Colpepper County, virginia. Per the Rappahannock News. The development features a resort style swimming pool, a clubhouse, a tot lot, multiple sports fields, sports courts, all connected by a network of biking and walking trails, which isn't really different than a lot of the places down suburban DC. John, is it possible for new developments and population growth to exist without sacrificing the night?
John B:Bill, i think fundamentally the answer to that is no, but there are degrees of that, in the sense that we live with alterations that humans have made to the environment every day and we do so in a way that doesn't materially affect the quality of our lives, because we've managed to bring pollution sources under control. I think that's sort of the best of what we could hope for. As Ruskin mentioned in his quote that you read, you know we've been using electric light for the lower 100 years and at this point there's really no going back. We can't reset the world to the way it was before there was light pollution, but what we could do is look at creative ways to limit the further growth so that we don't have to sacrifice the conveniences and the benefits that artificial light at night brings. But we can try to prevent sort of the worst of the damage to the environment, and all the time we find out more information about exactly what that is.
John B:One approach that people are thinking about is limiting the rate of new growth of light in the world to sort of the rate of growth of the human population, and you can think of it as a lumens per capita, the way that we measure all kinds of other things per head of population, and that number varies quite a bit depending on where you are in the world.
John B:We use a lot more light per person here in the United States and Europe and other places than the rest of the world.
John B:But you could look at an area and say, all right, you know there's so many people, there's a certain amount of light that we see from satellite images, for example, and you divide one by the other and you get a number. And if we could restrict the growth of light to about keeping that number level over time, i think we could head off sort of the worst of what might be coming. But otherwise, without any meaningful controls on that, what we have seen in the last decade or so is that the rate of light that's appearing on the Earth at night has been growing at a rate that's about double that of the population growth on average throughout the world, and in some places it's a lot higher than that. So the first step would be saying all right, what's a reasonable number here? Can we contain it to that number over time so that if you're adding light in one place you're taking light away somewhere else, to try to maintain something like a balance?
Bill M:So in this area, this Rappahannock has a IDA designation, as an international dark sky designation Is to your point. if you're going to have more people move into the area, is it going to ever be sustainable to be able to protect those places?
John B:That's a question that we just don't know the answer to yet. Again, i think we can do a lot with lighting design and public policy that governments how light is used at night to try to limit that as much as possible. But even if we got to a point where the light consumption per person, as it were, were held steady and we were only seeing changes that reflected population growth, then you still have that problem where, over time, there will be more light as there are more people And as people increasingly concentrate into built-up areas and cities around the world. The cities are really the source of a lot of the problem, and one thing that we know from research is that that light can reach very large distances away from the source. So even if we said, all right, well, the city is growing at a certain rate and there's only so much we can do, the cities get brighter.
John B:And even if we sacrifice the cities and I don't think we have to do that, but if we did, it is not as though their light is just purely contained within the area around the city It's going to reach, in some cases, hundreds of miles away from where it's generated and it's increasingly intruding into areas that have otherwise been largely protected up to this point, and we don't really know what the solution to that is yet, although over time, you know, maybe technology will yield ways to use light, and increasingly efficient ways, to the point that we need much less of it to get the job done. And I think maybe that's the best that we can hope for, that we can settle into some sort of new equilibrium in the future where again we're providing for the needs that people have that are very legitimate at night, but we're also not going overboard to the point that we're now beginning to affect the well-being of wildlife, that's, you know, maybe hours away from the source of all of that light.
Bill M:Right or maybe not. Maybe 15 minutes, or maybe even a few feet away from the source of that light. It is springtime and you can definitely see all the bugs congregating around these LED lamps. Caitlin, do you have any thoughts on that?
Kaitlyn E:Yeah, i thought a good point they made in the article was that you know the homeowner that had all these bright lights. once somebody pointed out the fact to this homeowner that he had, you know, a great view of the sky, that this was actually a valuable resource, he began to feel protected of this resource. You know someone said to him hey, you have this valuable, scarce resource like you should be proud of this thing, and I think maybe, just like some education and giving people like a different mindset like you know, telling them this is a valuable resource, like that could maybe, you know, go a little ways and convincing people to try and take some steps towards protecting this.
Bill M:Yeah, i don't want to hit on it just yet, but I definitely think when you lose a resource and you didn't know whatever existed, you know that's something that we're looking at as a. We're looking at a night sky extinction, right Like that's something that could possibly happen in our lifetimes. So, yeah, we can get in. We'll get into that a little later, but how about we move on to the next one? I like this conversation we're having here. This is good. So full disclosure. I came across this article, actually in a paid ad in Metta. The article itself is from January 22. It's been old but it's not untimely And I enjoyed the article and I thought it would be pretty interesting just to bring the topic into the Intel PN. The Forgotten Medieval Habit of Two Sleeps And that's by Zaria Gourvet of the BBC Gourvet opened my eyes to something I never knew about the medieval custom of two sleeps.
Bill M:For those of you unaware, two sleeps are exactly what it sounds like. Folks have partaken a communal nap, complete with rigid sleep arrangement conventions, sometime around 9 to 11 pm, and then awaken for a few more hours to do everything from hangout to brew beer. In fact, the idea of multiple sleeps crossed cultures and was found in places as far away from Europe as indigenous South America. How can one circadian rhythm make sense of all this? Well, for starters, until the invention of the alarm clock which Gourvet points out was humorously invented by a clock salesman who couldn't wake up on time, so he created an alarm clock. Very good on him People had no firm way to wake up on a consistent time. The Industrial Revolution enforced a whole new circadian standard, and there's some size behind this. In a 1992 study, these short-footed periods human sleep in biophasic researcher Thomas Weir found after four weeks of 10-hour days. His subject began to engage in this two-sleeve cycle involving one to three-hour periods for which they became awake and engaged in between.
Bill M:In Paul Bogard's End of Night, he mentions repeatedly that documents from the Middle Ages only recalled nighttime being used for crime. Even Gourvet couldn't help herself, but right criminals took the opportunity to skulk around and make trouble. However, gourvet also paints a varied use of the time known as morning sleep, which is the second sleep To me, this makes plenty of sense. The tendency to describe darkness as evil is a medieval legacy that we still have yet to shake to this day, despite the fact that great majority of crimes happen when most people are active And granted a lot of the information. The base information that they were able to ascertain for the two sleeps came from criminal complaints. So, john, i'm curious what are your thoughts on the two sleeps? Is this how we came up with so many great astronomical inventions over time?
John B:It is kind of interesting to be able to think about people in sort of the pre-industrial world that didn't have the access to light at night even oil lamps, candles, that sort of thing being more active and therefore looking at the sky at night and they were more in tune with it or they were thinking about it more often. There is a lot of evidence that has come about since the time of the where paper from 92, both for and against myphasic sleep in humans. What's interesting to me is that no one's really come up with a good working theory for why humans should have this kind of sleep pattern as opposed to some others. Because we see it in nature. In other animals We see polyphasic sleep, where they're awake in sleep and awake in sleep throughout a period of time. And then we see animals that are so-called monophasic sleepers. They only they go to sleep, they stay asleep for some number of hours and then they're awake. But there's a huge diversity in the animal world of sleep models, as it were. But we just don't know why. In humans, what would be the evolutionary advantage of having this sleep pattern?
John B:One suggestion is that humans are subject to becoming prey for predators at night and that they needed to have at least a little bit of wakefulness during their sleep cycle in order to stay safe, and we've seen evidence for and against the the two-phase sleep cycle and people that's emerged in about the last 15 years or so, and I think at the end of the day it is probably more complicated than that.
John B:It's not a simple function of our light exposure or what our, our culture has to say about sleep. It's a bit more complex than that, and I dug up a quote for this from my colleague, anne Alsbrook, who's now a postdoc at the Max Planck Institute for Ornithology in Germany. She did some research on this when she was a graduate student at the University of Melbourne in Australia, and a few years ago she wrote that since the invention and widespread use of electric light, there had been other social, cultural and technological changes that are also likely to have affected sleep, and so she concludes that it's difficult to isolate the role of just artificial light at night on sleep if all we look at are historical records. So I think the the the case is very much not closed and that there's still more that we're going to learn about how people sleep.
Bill M:I'm amazed that they woke up, brewed beer And then went to bed again, that I mean it takes a good three to four hours to take care of. You know at least part of the process. But that blew my mind. But that's a very it's very interesting to imagine a world where you didn't have a strict, you know, nine, 10 o'clock to six, seven o'clock.
Kaitlyn E:And I wonder if any of that could have to do with, like, seasonal darkness and latitude, like you know, in the winter, when you have these long, long hours of darkness, like maybe the human body just doesn't want to sleep for 12 hours, maybe it needs to break it up into, you know, more manageable chunks of sleep.
Bill M:Oh, that's an interesting point You're saying based on the amount of daylight you naturally receive.
Kaitlyn E:Yeah, like if you're in a Northern latitude, like during the winter, like you're probably not going to sleep 12 to 16 hours.
Bill M:Johnny, you aware of any studies that looked at the actual impact of overall daylight?
John B:Yes, and and Kaylin may be onto something there There's a paper that was led by a researcher named Gandhi Atish about eight years ago that looked at three pre-industrial societies, mostly in the equatorial regions, and their group did not find any evidence for this two phase sleep, and they think this is their kind of working hypothesis for what's going on. They believe that until humans migrated out of the equatorial regions and towards the higher latitudes, that this seat pattern probably didn't exist in humans, and their conclusion from their paper was that they think it may have been a consequence of longer winter nights at higher latitudes. So that idea might be exactly what did it, which means that in the distant past there wouldn't have been this two phase sleep. We were all just monophasic sleepers, and as humans migrated eventually, you know, to higher latitudes, especially in the Northern Hemisphere, they ran into these large seasonal differences in the duration of the night, and that's what encouraged them to become two phase sleepers.
Bill M:It's pretty interesting, pretty interesting. This is Kaylin little workings there, so time for some quick hits. How about we jump into just a few here? You want to learn about light pollution? There's a mini course for that. Jennifer Sensible of Clean Technica has a link there. Quoting Sensible, as I got older, i traveled a lot more and solved a problem more for what it is. Not only did I see that in many places there is no refuge from it, but I also saw that it was slowly growing worse. Places that have been dark 30 years ago have more and more light creeping onto the horizon. If you're interested in learning more and, more importantly, know someone who might be benefiting from learning more, sensible links up to a international dark sky mini course on light pollution light pollution 101. You can just go right to that link and it will give you a little overview. John, do you have any background on it? Did you play hand in, or is that just the IDA with that one?
John B:on it. No, it's IDA. I used to be on the staff there and it's something that we talked about putting something like that together for quite a long time, so it's nice to see that it's finally ready and that people can begin to use it and benefit from it.
Bill M:Yeah, yeah, i saw it on a link and I clicked it and I asked Michael Reimer us. He asked me hey, is this real, is this legit? And he's like, yeah, where'd it come from? Next up there's a play date at the National Museum of Natural History Lights Out exhibit, an exhibit we spoke about previously, where you can go down and learn about the effects of light pollution. But unfortunately the play date has passed by the time we listened to the show and hell by the time we recorded it. But I just want to throw that in there that they are doing some cool things. Keep an eye out The National Museum of Natural History with their Lights Out exhibit.
Kaitlyn E:I did see they have one coming up June 27th, so I haven't completely missed it all.
Bill M:Okay, great, yeah, i didn't see a new one scheduled, but that's great to hear. I guess they probably have it every month. I'm thinking, yeah, well, that's kind of fun. And then, evidently, gambling websites have decided to honor April's International Dark Sky Week and a strange new content marketing campaign, and which was to rank the best places in each state to see some rises in the sunsets, with my favorite one, ann Arbor, named Best Place for Sun Rises Sunsets in Michigan, which comes to us from Click on Detroit, whereby a quote study examined Michigan's most popular cities. According to Click on Detroit, to celebrate International Astrology Day on Saturday, which was the International Astronomy Day, staff at Great Lakes Stakes, a Michigan online gambling news site, looked at the light pollution levels in the five most populated cities around the Mitten and determined which offers the best viewing every morning and every evening. So I'll just let you guys enjoy the paragraph for what it is, and we have one more, one more astrology item to talk about here.
Bill M:Starbathing is now a new outdoor travel trend that we should all be trying for 2023. According to Amy Beachham at Stylist, evidently as an attempt to distress and promote mindfulness, romanticism about sleeping under the stars has birth a 70% increase in searches for the term starbathing on hip camp And, to be sure, hip camp recommends checking a stargazing calendar which outlines a major astrological events like supermoon, pink moon, star showers, many more. It's always good to be planning your trips around those major astrological events. Let's take a breather here, folks. I wanna thank my guests today, john Barentine and Katelyn Evans. John, the pleasures are as you have you on the show. Is there anything you'd like people at home to know about Any projects you're working on, any big things coming up to keep an eye out.
John B:Yeah, bill. I mentioned a little while ago that I'd previously been on the staff of the International Barker Sky Association. I've been immersed in this world for about the past decade or so And prior to that, my background is in astronomy And I did that professionally for a number of years. I would say at this point in my life that my mission is to try to help people see the stars and experience a sense of connection to the cosmos or, among other reasons, that it may lead them to have more concern for the protection of our planet, and it goes in line with the broader sort of science communication goals that I have, which is to get people thinking about these really big issues that confront us as a society and as a species that we're gonna have to deal with this century, and to hopefully get people thinking about this bigger picture And if they can focus a bit on the universe, they can realize that we're just one small part of this and that we need to do everything that we can to protect our home.
John B:Something that I do on the side sort of is that I'm also a historian of science in an amateur sense, and I work a lot on history of astronomy And a lot of what we're faced with right now not only in light pollution, but bigger questions like climate change certainly has historical precedence that we should know about, because it helps us put into context what we're going through and compare it to what people experienced in the past.
John B:What to keep an eye out for coming up, something that's changing our world right now very rapidly And I know we're gonna talk a little bit more about coming up is the influence of all of these satellites that are being watched into orbit around the Earth right now Many thousands of them. The number has more than doubled in just the last two years, and it's changing our night sky very quickly, and that's true no matter where you're at in the world. So what I'm telling people is go see the night sky now, while it's still possible, because it may not look like this in a few more years. And if you are listening to this and you're in North America or can get here next spring, there is a total solar eclipse coming up on April 8th of next year, and if you are anywhere near it, please go see it. It will change your life.
Bill M:Yeah, it's incredible. I saw the one in 2016, right 2017. 2017, down in Tennessee, saw it down near Nashville And that moment when everything goes dark is magical. There's nothing like it.
John B:There's nothing like it.
Bill M:Yeah, wow, Caitlin the other half of today's panel, So very glad that you're back with us. For those of you not aware, Caitlin actually works hard behind the scenes here at LPN handling articles and the Instagram account for late pollution news. Is there anything new going on in your end?
Kaitlyn E:Yeah, i would always just recommend checking out our articles. A lot of them are focused on how to use outdoor light in a home environment in a dark sky friendly way, because we realize this is something people are gonna do. We're not gonna be able to tell people no lights outdoors ever, so we're just trying to give people options for how to do this in a responsible, dark sky friendly way.
Bill M:Yeah, we do have plenty of articles out there on light pollution newscom. Just definitely over at our website, check it out. We have show notes for all of these shows including all the links, and you can actually listen to the shows right there on the website, light pollution newscom And, of course, our Instagram lightpollutionnews and Reddit late pollution news. Let's see what else went down in May. This is an interesting one. It came to us in a PR piece that was very much unlike most PR pieces. I see out there.
Bill M:Industry must face an inconvenient truth Most LED lights at night are unhealthy. Dr Martin Moore Eid, a circadian clock expert, recently published an article in LED Magazine chastising the lighting industry for not recognizing and reining in the negative externalities of its product. Pr piece, such effects being obesity, diabetes, depression, cancer and more. He cites three categories of industry responses, making the correlation that long-term denial and outright ignorance of the facts may result in an asbestos scale, liability or even draconian regulations. Pr piece. The recent survey by the circadian light research center of 2,697 peer-reviewed scientific articles confirm that the human circadian clocks are highly sensitive to blue wavelengths and that exposure to such wavelengths can lead to major health disorders. Moore Eid calls for the industry to harvest the commercial opportunity to greatly limit future liability by creating and managing its own standards for circadian modulated lighting. This is something that Michael Colligan over at the Restoring Darkness podcast clamors about very often. John, have you heard anything from lighting industry in regard to any kind of responsibility for their products?
John B:No, i really haven't lately, bill. One thing that we can say is that with the introduction of LED in particular, it's not as though there's some obvious public health crisis that is related to this. There was a time several years ago when at least the rumor mill involving people in the lighting industry was that lighting companies were starting to look at their potential exposure to legal liability because of their products. Given some of the stories that were out there at the time, i'm not aware that any lawsuits were filed or that anybody's planning anything like that. Part of the reason is that we just don't have a good handle on the science side relating the exposure to this kind of light to specific health problems in specific individuals. We have sort of population studies where you'll look at the incidents of certain kinds of disease like the ones that were mentioned diabetes, obesity, cardiovascular disease, et cetera in large group of people in epidemiology studies And they try to link that with the amount of light that we think is there in their environment using satellite measurements.
John B:We don't have a lot of direct measurements of. Think about people in their houses at night, where they get most of their light exposure indoors. Are they getting it from staring at their screens too late at night? Are they watching TV? Are they getting light coming in around the coverings on their windows from outside sources? There was a health researcher named Richard Stevens He passed away a few years ago, but he was a long time and very well recognized researcher in this area at the University of Connecticut And he told me that we really had no idea, and we still don't, what the consequences of a low level of light exposure chronically every night for years and years, especially in sleeping rooms like bedrooms.
John B:We don't know what that does to people in terms of their health.
John B:We don't know what the exact relationship is between the sort of the dose of light that we get, so to speak, and the resulting reaction in the body other than in these sort of large population studies.
John B:And so we can't draw a direct line from one to the other, and I think that is the weak link right now. If we study these groups, we can conclude that too much light at night for you is probably bad and that it is linked to these disorders. But if there were a cause for legal liability, you would have to be able to say because an individual's light exposure history resulted in them getting plastic cancer, for example, or developing diabetes. It's going to be really hard to establish that from a legal perspective, so I'm not aware that anybody in the industry is really worried about this right now. I think it's being chalked up to sort of a general sense of lifestyle, especially in Western countries. But there is always a possibility, as we learn more, that we'll find out there is some threshold And if you regularly exceed that under certain circumstances, then your probability of developing these diseases goes way up And we may eventually have to confront that as a society if it starts to become a drag on the cost of delivering health care.
Bill M:Yeah, yeah To your point, John. I think trying to compare it to an asbestos-scaled liability is a bit. It's alarmist. I don't think it's really realistic. Asbestos is very easy to kind of measure And you can identify the actual illness within the lungs, but for light, light is a little different, unless you're going to do, i guess, a survey of everyone who works a night shift for 30 years, and even at that, how do you discern out other issues that may have come up? I suspect, and I've always wondered if you're working a night shift for 30 years, your normal habits are probably going to be different from the fact that you have to kind of fit your body into that night rhythm. So things are going to be kind of stressed and changed because everyone else is operating under a different schedule than you. So I've always wondered how much of that is. Maybe people who work those night shifts may have additional issues going on just from the fact that they're kind of the oddball in society. Society doesn't really make time for them.
Kaitlyn E:Yeah, and this issue kind of makes me think of like we're talking about pollution. You have your point source and non-point source. You're getting these this light, you're getting these inputs from all over. You're never going to be able to point to any specific source And you have all these other environmental inputs, so it's going to be really hard, i think, to tie anything to one thing specifically.
John B:And to your point, bill, there are studies like the kinds you're describing, looking at shift workers over the span of 30 plus years, where efforts were made to try to control for all of the other lifestyle factors which, if we're talking about cancer for example, that's an incredibly complex human disease that has lots of potential origin points And there is a signal that remains even when you try to control for those lifestyle factors. So we really do have reason to believe that chronic exposure to light at night is bad for people, and I mean it's a simple hypothesis that seems to be borne out every time we do a test. but it's exactly what Caitlin just said Isolating that as opposed to something else in individuals is really tough. And it's even more difficult if you're trying to make a case that it's something like a liability on the scale of asbestos or cigarette smoke.
John B:And in the asbestos case, of course, for a long time before it was realized that there was any human health effect, everybody thought it was a great thing right. And we still sort of have that mentality with light. is that it's a great thing, it's beneficial to us at night. How could it have a downside? But you kind of have to get outside of that mentality and open yourself up to the possibility that this thing that seems great on the outside might be a problem before when you begin digging into it, you see evidence for that problem starting to show up.
Bill M:And that's an excellent point. Curious I thought that was interesting that someone was actually calling out saying that we need to look at how we use light. We need to take a step back and question it and say, hey, are we doing what's best for people? In a similar vein, this one comes to us from Reddit Unpacking the Wall Pack by Dan Weisman in LD Plus, a magazine. Weissman, who recently purchased a telescope for his family in Cambridge Massachusetts, discovered that the scope could only afford him views of some solar objects and a few brightly burning stars.
Bill M:The ire of Weissman's pen takes shape in the form of rectangular fixtures, be it box-like or simply a panel. These days, these light fixtures typically can be found hanging on an exterior wall or above an exterior door. With a lot of aesthetic value, this light is often put up under the pretense of security and safety. By recommended practices and adopted municipal codes.
Bill M:Weissman recognizes labels that often accompany what he calls glare bombs, including contractor select, energy efficient and light pollution friendly. Further, per an earlier LD plus A article, such lighting, driven by its extreme contrast, is exceedingly common in minority communities, where light is weaponized as a tool of power, it becomes a device of alienation, creating a zone of control and separation. Weissman recognizes that the true reason such fixtures are often selected is driven by cost. It may take equally as much cost to persuade building and homeowners away from such lighting in a realm of more responsible, lower-lumen lights. Weissman calls for producers of these glare bombs to be labeled as polluters, putting them in line with fossil fuel manufacturers and PFAS makers. Is Weissman right? Is it a bit extreme to label these manufacturers in the same ilk as a petro or chemical industry?
John B:I think there's no doubt at this point. We have a lot of evidence that artificial light at night is a pollutant and it is as powerful and potent a pollutant as chemical pollutants, for example. It's having that series of an effect on wildlife, on the nighttime environment, etc. So can we say that this is pollution-sure? I don't know that we can put this in the same category as something like oil companies affecting the climate. There's attempted litigation going on. There are people that are trying to change laws where that's concerned.
John B:There's this notion in environmental law called polluter pays. So if you do damage to the environment because of your product, that you should bear the primary responsibility for correcting that. Should consumers know about the risks that are associated with the products they buy? Absolutely, if those risks are clearly identified and backed up by science. Yes. If it's speculative, that's a little bit harder to accept. But I don't know that we want to put big black box warning labels on lighting packaging and say that if you buy and use this thing it's destroying the environment. It really depends on the context in which it's used. Should we allow sale of glare bombs like wallpacks? I think it's arguable that if that's what the people of an area, town or town or whatever. If they choose to allow it or prohibit it, they should be allowed to do that.
John B:If we decide that artificial light at night is a pollutant at a certain level and we treat it like other forms of pollution, there will probably be some federal regulation coming down the road that limits that. You might not have that option in your community. It's no different than the way that we handle air and water pollution. If you buy a car, you can't opt to not have a catalytic converter. We're long past those days. I can foresee a future in which, probably at the federal level, there's a recognition that light is a pollutant and that some kinds of things that generate light are more polluting than others. They may be subject to more strict regulation in that regard. But I just don't yet think we're at the point where we're yet seriously talking about that sort of more extreme action in response to this problem.
Bill M:Yeah, to that point. I wonder, when we have a lot, of, a lot of times with the glare bombs, there's not as much recognition of the environmental impact or ecological impact, but much more on a nuisance impact. From that standpoint, do you think there's any validity in just being able to have best practices around having these products sold with shielding? Do you think there's any validity in just doing something as simple as that?
John B:I do. Sometimes we talk about in this business whether we're treating so-called the supply side of the problem or the demand side. And the supply side is the existence of light fixtures that have a lot of glare. People like them. They use them for security lighting. It's not so much as what it does to the person that's the recipient of that light, but it makes the owner of the property feel better because they're lighting up tonight. They use this sort of what's believed to be common sense to say that that will prevent people from doing the various things that night around their property.
John B:We don't really have any evidence that works that way, but that's what people think. We could deal with the demand side if we added to local lighting ordinances, for example, a prohibition on what we call light trespass. That concept says that if you emit light on your property, you are obligated to ensure that the light stays on your property. If I can draw a direct line in space, i can follow a light ray from the source of the light, from the lamp itself, and that lands on somebody else's property, no matter how near or far they are. Then we would say that light trespass is taking place and we could write a code that would prohibit that.
John B:If that became predominant and there was a lot of public support for it and it was well implemented and enforced, i think you would start to see the market demand for those kinds of light sources drop off precipitously. There are shielded wallpacks. You can buy that right now. If they are installed correctly, they will completely prevent that sense of trespass. But until people know about that and choose that style of light fixture, unless there's a prohibition on the trespass part, you're always going to have people that are just blasting floodlighting in every possible direction because it makes them feel better about themselves at night. So yes, i think we can work on problems like that from both directions and in places where we're implementing that we're starting to get some good results.
Bill M:And where are we seeing that implement it?
John B:Any of the international dark sky communities that are recognized by IDA my hometown here, tucson, arizona. We have a great outdoor lighting code. You don't see a lot of really great glaring sources around at night. Towns like Flagstaff in Northern Arizona, the world's first dark sky city. It's been shown it can be done. Where it usually fails is it's the enforcement side. If somebody puts up a glare bomb in contradiction to what the law calls for and nobody raises that issue with the municipality, people can make grumble about it but nothing will ever happen. So with any kind of change to the law, we have to have some program of education and awareness that aims to increase the public support for these proposals and these. What become policies? And what you want in the end is a lot of voluntary compliance, because no community wants to play bad cop and go tell people that they have to disconnect their lighting. It's just not popular. So if you get that groundswell support on a popular level because people support the policy, i think the chances that the bad stuff goes in are greatly reduced.
Bill M:Why do you think it's not popular?
John B:It's not popular for a couple of reasons. One is there is a really strong human psychology that makes us afraid of the dark and it just makes us feel safer if the outside spaces at night are more like they are during the day time. As I said earlier, there's not a great deal of evidence that it works that way, but that is what is in our minds And you mentioned sort of the inheritance of the medieval world and that we still talk about light and dark in a sort of good and evil sense. It's very pervasive.
Bill M:All of our phrases. Darkness is always bad and light is always good.
John B:Absolutely. It's really deeply ingrained in our culture. But don't overlook the possibility that a lot of people really feel this in a visceral way. They are viscerally afraid of the dark and they will do anything to try to avoid it. The other thing that we confront a lot is the notion of private property rights and people saying I just simply don't want anybody telling me what I can do on my property. If I want to light it at night, because I'll feel better if the light is out there, I should be allowed to do that and the community shouldn't have anything to say about that. Always, a course is depending on where you're at, but that's another influence that we see quite frequently.
Bill M:Yeah, yeah, caitlin, do you have any thoughts?
Kaitlyn E:Yeah, I was just going to ask like, do you find that people that are being protective of their rights for their private property, are they open to educational opportunities? Like when you show them like the glare bomb wall pack versus like the fully shielded? you can show them, you can still get this much light and you actually have better visibility. when you don't have the glare bomb, You can actually see what's going on a lot more. Are people receptive to that or do they still tend to resist that?
John B:It's a little bit of both. Caitlin, i'm glad you asked that question. I think certain people are always going to be receptive to these ideas, especially if you show them, if they can see it for themselves. It makes a very big difference as opposed to talking about it in the abstract.
John B:The other tactics that I use when talking to groups whether they're, you know, citizens, groups, city councils, that sort of thing is that I say you know what? I think you're right, i think property rights are important And I think that's something that comes along with our rights, our responsibilities, and one of those is to ensure that your neighbors also have their private property rights. And that's when the light bulb, figuratively speaking, goes on and people say okay, i see what you mean. That in the sense that I should be able to do what I want with my property. At the point that it becomes a nuisance to my neighbors, i'm depriving them of the same right. And a lot of people take exception to that. They don't like that idea because they flip the situation around and they say well, i wouldn't want my neighbor doing something that's infringing on me, and the best example that I can think of that I always use when this comes up is.
John B:I'll ask the same people that are resistant to having limits like this, like a light trespass provision in their code Does your town have a noise ordinance? They'll say, yeah, you know, like what do you do when your neighbors are having a loud party and it's early in the morning? Well, we call cops. right, because you have an understanding with sound that you can create a problem for your neighbors that interferes with their enjoyment of their property. Do you want to be on the receiving end of that? And they go oh, no, no, no. So if I can get through on that, and then I can show them an example of how better lighting is, really better it changes things And I'm surprised at the number of people that are receptive to that.
Bill M:That is excellent. I love that approach to it, john. That's a very clever approach, a very smart approach, very logical approach. We see this you go camping nowadays I don't know if how it is out west Good camping and you have RVs that you know everyone usually abides by the noise ordinance, but then RVs will light up their surroundings like it's kind of some kind of prison camp. and I'm a tent camper and it doesn't make for great nights. You know you can't sleep when you have everyone trying to light it up like a truck stop. But you know, maybe you should knock on some doors there and hopefully we won't get shot. So I think this may be a piece. this may be a spot too where you want to talk about lights, impact and actually influence people's decision making and influence their hearts.
Bill M:On the ecology front, we take a closer look at our avian friends. This is from the Washington Post songbirds, dusk and clear skies, scientists exploring migratory flights and this comes from Aaron Blakemore. Bird migration season is ending here in the mid-Atlantic. I was lucky enough to catch several orals and indigo bunting last week. and okay, lynn, you found a. Canada warbler. Researchers looked at 400 songbirds and 9 major species, including the yellow rump warbler, the American red star and the bicknull's thrush. The question I hope to answer was how are these birds so darn precise in identifying the best time to take off for their nightly migration? Scientists found that 90% of the migrating birds in the study took off within 69 minutes of dusk, a much narrower takeoff window that even shocked the research team. Per to study, taking off at night is all about maximum flight time. In addition to being able to precisely schedule their takeoffs a feat that every airline I've flown with over the past few years has proven vastly inept at, birds are also apparently good meteorologists. They often depart when the atmospheric pressures rise over the span of a day. Other factors that also trigger migration are sex, age and celestial cues. We spoke about that in a previous episode, where birds will actually use star patterns and lock in on star patterns in their flight.
Bill M:Since we're talking about migrating birds, this one comes to us from WHIY in Philadelphia. The Lights Out initiative appears to be saving birds from crashing into buildings by Sophia Schmidt. Pseumonary results indicate that bird death counts are down 70% at one Marcus Street tower since it began participating in Lights Out. Combine the lights with reflective or transparent glass and that spells fatal trouble for our migrating warblers. Per Keith Russell, a program manager for urban conservation with Audubon Mid-Atlantic, we've lost almost a third of our birds. Collisions are contributing to that. If we're going to want to preserve the bird populations here in North America, we have to take a look at these types of problems, and this is a preventable one. What are your thoughts on birds? You know nighttime and birds have become a big topic over the past few years.
John B:We know more about this Bill than we do how those same lights affect people. Relative to our conversation earlier about how it was having effects on human health, We certainly know from research that it's a risk to many bird species, especially those that migrate. The probability that they will collide with building windows is really high, and that's just for the sort of species that are urban resident or spend a lot of their year in cities. The ones that migrate it's a whole different story because their migration pattern is so tuned, like you said, to all these environmental cues, including starlight. If they see a lit city on the horizon in the distance, many of them will be drawn off their route because they're attracted to that light and they get into a downtown situation where there's lots of light sources and lots of vertical surfaces with building glass It's reflecting that light. They become confused and if they don't drop dead from exhaustion, they will collide with windows.
John B:It's vastly underappreciated the effect that this is having. If you think about the decline in bird populations worldwide that has been observed going back to the 1970s, and knowing that this is a component of that we find so many of them that die in cities at night Then you put into context that this is just one stressor that a lot of these species are experiencing right now, that climate change and habitat fragmentation and loss of biodiversity in a lot of areas is affecting them just as badly. It's really starting to put a lot of pressure on these species. Of course, they're connected to the rest of the web of life. If you start messing with that at one side and pulling on these threads, there are consequences that we probably don't even appreciate yet As to why this keeps going on.
John B:With the light aspect, people think of it as an out of sight, out of mind kind of a thing. We're not out there at night, during the overnight hours at least, when these birds are making their migrations and they're dying in these collisions, and they don't see it, they don't know about it and they don't care. Can we change that? That's the hope, partnering with organizations like Audubon to raise awareness of this. Lights Out programs are great, but it's the same way. We need people to think about this as a bigger problem that is going on every night and not just something that's limited to migration season.
Kaitlyn E:Yeah, i think the Lights Out campaigns have been great for spreading awareness about this issue. I know they've been able to reach out to people not just in city areas like that can be suburban residential areas. The majority of bird window collisions are actually residential, not urban areas. So it's a problem everywhere and I think they are doing a great job of trying to get the word out, get people more aware of this issue.
Bill M:One of the things that Keith Russell has mentioned to me regarding strength of Audubon making this argument, being able to convince major players the major player here in Philadelphia to be pulled in that shifted the whole deck of cards with Comcast and the Comcast towers. When they got the president of Comcast on board, everyone else fell into place. And how they did it was through essentially counting how many dead birds were around the building each day and that having the data and having those numbers they could make present a strong argument. John, i feel like that is the Achilles heel to a lot of the dark sky issues we see here There's a correct me where I'm wrong. Do we have data? Do we have enough data? Do you feel like you can make strong arguments in a way that Audubon can say hey, there are a thousand birds that died from your tower tonight?
John B:Oh, yes, directly. We have data from efforts that have gone around cities at night, particularly in North America, counting bird carcasses, collecting them, categorizing them by species, et cetera, and then we can extrapolate from there to account for all of the world's cities on all the nights of the year. And I've heard estimates ranging from, on the low end, perhaps a couple hundred million birds a year, to as many as 10 billion in a year.
John B:These are huge numbers right. I mean, if people could see that, i think they would react to it differently. So we've got the numbers right.
Bill M:I can't even think of them. I can't even imagine what 10 million is.
John B:Yeah, yeah And it goes on every night And again. What the concerns about how the birds fit into this bigger picture? But Audubon, like a lot of organizations, is up against a lot of threats to birds right now And the tough thing is just kind of holding attention on any one of these issues for long enough to start to make especially policy differences. If anything will change the tide, it will be that, but first we have to get the owners of the affected properties to understand that for as much as they are part of the problem right now, they are also potentially part of the solution.
Bill M:Caitlin, do you have anything to add on that?
Kaitlyn E:I know, i think John covered it pretty well.
Bill M:Yeah, one last piece I'll add here. John Audubon's been aware of the connection between lights and birds for over a hundred years. This is something when they and I forget where Keith was telling me, but when they installed an early light on the tower.
Kaitlyn E:It was the first city hall building.
Bill M:First city hall building here in Philadelphia, was it?
Bill M:Okay? So the first city hall building. When they installed the light, they noticed it already started having bird collisions And it's something that has been a researched item for you for a year. Okay, well, we've been a little heavy here for a few articles. How about we do some quick hits and keep the show moving along?
Bill M:The Knoxville Tennessee zoo is offering up what they call Twilight Hours per WVLT-8. Each event will feature a guide to showcase nocturnal critters. I did something similar in Singapore years ago. The zoo had. It was cool. It had very dim lights in the exhibits and it kept the lights kind of dim in the hallways too, as you walked around, as you walked through. It was very, very neat. You didn't really lose your night vision. You didn't really have full night vision, but you didn't really lack. You're kind of in that in-between zone where you can see things. It was very different. It was peaceful, it was cool to see, you know, alligators walking around at night. I don't know. It was a very interesting, not chaotic experience. It's very mellow And I would say you know, star bathing-ish, if we're going to use the article we spoke about earlier today. Have any of you guys ever been to a night zoo?
Kaitlyn E:I have not. No, yeah, i would imagine the animals, at least some of the animals, be more active, though with cooler temperatures versus, you know, in their normal like hot zoo environments and places somewhere like Knoxville That's probably pretty warm in the summer months. I'd imagine they're a little more active in the cooler nighttime temperatures.
Bill M:Sad news from Fox 35. In Orlando, florida, flashlights are posing a major threat to nesting sea turtles. Apparently, a single flashlight can deter female sea turtles from coming on to the beach and nesting. Florida, as I did not know, is home to 90% of the sea turtle nests across the world, so losing sea turtles can affect the global ecosystem. One visitor to Cocoa Beach stated that why don't we just leave them alone, stand back, look, you don't need the flashlight. But another says not surprising, because more buildings that go up, more technology and as it all increases, nature and stuff like that decreases. That's sad commentary, but Florida has done a lot for trying to trying to protect sea turtles And you know I don't know, i don't know how you prevent those flashlights. I know, being down in Florida this past March, you know you have people go out there every night with their flashlights looking for shells and stuff.
Kaitlyn E:Especially, everyone has a flashlight on their phone. now There's not really any way to tell people not to use them. Everyone's got one.
Bill M:Right, right Captured to dark 2023 is officially under way. International Dark Sky Association opens up their annual photo contest, complete with prizes across eight categories and an additional people's choice category. Voting will begin on July 3rd. Entries must be received by June 30th. John, do you capture any good, good photos down, like just you know, just with your regular old camera? Do you capture anything good?
John B:Oh, certainly. We have incredible landscapes out here in the West that really lend themselves to nighttime photography in particular. I'm not a huge photographer, but I know people that are, and the views are just stunning, and it's becoming increasing and easy for people to do this. I've seen people get great results now with just their camera phones. That's really come a long way in the last few years.
Bill M:Yeah, we were talking last month. Last month, bonnie Bonnie Pang was on here saying how you know, you can actually use a little Samsung phone and it's very cool what you can do these days. Hopefully that garners appreciation for it, right? Hopefully it garners appreciation for it. I don't know many other ways you can actually tangibly have like something from the sky, right, other than the image you made that has the Milky Way. It's very cool.
Bill M:Well, good luck to anyone who's entering that. We'll see if I can find some kind of picture, but I don't know if I can compete with you guys out West. You guys have just too many advantages. And hey, you better not speed in a Rosserd Quebec, otherwise you may be waiting around for quite a while. Rosserd is testing out a new traffic light that will stay red until a census on coming traffic. However, there's a catch It will only change to green if the car is going to speed limit. Per a Jalopinic article, fred, the French acronym for educational traffic, calming light. A calming light forces fast drivers to stop and gives them a chance to reconsider their life choices. Such lights are used in Europe, but this will be the first one in a great white North. This feels like an excellent time to take a breather. Still to come.
Bill M:We have a deadly afraid of dark segment, and why the greatest threat to stargazing isn't light pollution. But first I want to thank my guests. The great John Baratine We're so lucky to have you. The other end, i have Caitlin Evans, who handles our social media and a building of many of our great articles. Before we continue, i just want to thank you, the listener at home. As you know, we put a lot of time and effort in every show each month and building a great show. Just for you, please, if you're able to take a second to rate and review this show. Wherever you listen to podcasts, it really helps us out. It helps to raise us in the actual algorithm itself, whatever service you're using. And on that note, we launched a new support button whereby listeners just like you can help us offset things like server costs, editing costs and any promotional costs. All of those things do add up, so we're very grateful And for the price of a coffee, you can help us keep our lights shining just where they have to be. So finally, if you ever need to find any of these articles or anything more, just head right over to our site, light pollution newscom, where you can listen to all the episodes, read articles and learn more about Topic of Light Pollution. Our Instagram is lightpollutionnews And, not to forget, definitely join us over at Reddit on our light pollution news.
Bill M:Let's get back to the show. All right, why? the greatest threat to stargazing isn't light pollution? And this comes to us from Dora and Ellen Urida. At Inverse In her compelling piece, the greatest threat to stargazing is actually the weather, siting notable examples of the Mount Stromlo Observatory in Australia, which burnt down due to brush fires, and the Arecibo Observatory over in Puerto Rico, which sustained structural damage following the winds of Hurricane Maria. While the threat of human cause climate change has presented new challenges, she references proactive burns that actually helped save Los Angeles' Mount Wilson Observatory from wildfire flames in 2020. So I guess it probably doesn't help that most observatories are placed in an arid or drier parts of the world, especially in these days. John, what's your take on the number one existential threat to ground-based observing?
John B:Well, bill, i still think that what threatens ground-based astronomy most is light pollution. It's not to say that we shouldn't be concerned about the changes that are being brought about in the climate that is making a lot of areas drier. Certainly out here, where I'm at in Arizona, our climate is getting drier. That means that our forests are drying out. We were in the midst of a drought that started more than 25 years ago and is still ongoing to this day. Our national observatory at a place called Kid Peak, just west of Tucson, burned last summer. Fortunately, they were able to save almost all of the facilities, but we're seeing an increase in that sort of thing as a consequence.
John B:The other aspect of climate change and weather that's impacting astronomy is just an increasing number of clouds. in many places where we would build observatories that are otherwise under clear conditions for most of the year, they're starting to see more cloudy nights that are related to a warming atmosphere, but we've been dealing with clouds and even with forest fires for a long time. What's creating the biggest efficiency hit for astronomy and making it difficult to do science from the ground is the fact that we're losing dark skies. Keeping everything in proper context, yeah, we should be worried about these things, but I think there are certain of them that we can work on more easily than others that will produce big results. As long as we keep that in mind, that's what I think we should be focused on mainly in the future.
Bill M:Yeah, there's a lot of threats out there. I think really it's about the clouds. That kind of makes sense. What do you explain to me about the clouds and climate warming Right?
John B:As we have been warming the world through human activity in the last couple of hundred years, we're increasing the amount of heat from the sun that's being wrapped near the surface of the earth.
John B:It's the famous greenhouse effect that everybody has heard of. The atmosphere is holding more energy now on average than it did in the past. In certain parts of the world, for example, that drives more convective thunderstorm activity, so especially in places like the tropics. But that's beginning to spread away from the equatorial regions towards the temperate parts of the world, which is where we tend to build observatories. We never put them in the equatorial regions because the weather is just predictably bad all the time. But by the time you get out to 30, 40, 50 degrees away from the equator, the weather is usually a little bit better. We have places like the Atacama Desert in Chile where it's typically very dry, good place to do astronomy. But even there we're seeing an uptick in the number of cloudy nights, and it seems to be related to There's just more energy available to form clouds in the atmosphere than there was in the past.
Bill M:Right, right, wow. Well, on a similar note, the Australian Broadcast Company has an article out there this month A World Without Darkness Could Be a Reality Within a Few Years. Per Carol Redford of Ashot Tourism, western Australia. There are some people in the world who don't actually know what it's like to experience darkness anymore. They're in a city like Beijing, tokyo, london and all those big cities. It's never dark, it's always light. During the day, of course, the sun is up, but at night, with all the artificial light, it never, truly ever, gets dark.
Bill M:In 66 years, since the implementation of the UN Convention on Peaceful Use of Outer Space, around 11,000 satellites orbit the Earth, but it's about to get way busier, driven by innovations that have led to dramatic reductions in costs. Per Stephen Freeland, it's anticipated that somewhere between 100,000 to 500,000 objects will be sent up over the next 10 years And just let me pause it as 100,000 to 500,000 objects. Jon, we just spoke about how clouds are an issue. Does humanity really have a full appreciation for what we're about to do? Could this supersede even into an ecological issue?
John B:I think it's quickly becoming one Bill. To be honest, there's just no historical point of reference for this time that we're in right now in terms of the way that we're changing the Earth in general. We're changing the night sky, whether it's through ground-based light pollution or the increasing presence of satellites, as you mentioned, or what was implied by what you were saying a minute ago. There are a lot of people in the world now who live in places where there is enough light pollution that the sky never really gets completely dark at night. They live in this sort of state of perpetual twilight, and that has all of the consequences and concerns that we've been talking about for most of the show. The especially new thing is the phenomenon of the large number of satellites that are being watched, and it's still a bit like the Wild West, even though there are some international laws that govern that The orbital space around the Earth is almost treated like a sort of no-man's land. In the same way that we legally handle the situation on Antarctica, for example, where you're not supposed to claim territory, even though countries kind of do. Or maritime law, the law of the high seas, how do we deal with legal questions that arise in the oceans where, in principle, nobody claims territory. We have a treaty framework that is supposed to deal with the uses of space. That's been around, as you said, since the late 1960s, but it really doesn't imagine something like the uses that we're talking about now. I said earlier that the number of satellites in orbit around the Earth had more than doubled in about just the last five years or so, and there is a process at the United Nations that's supposed to handle resolving disputes, deciding on what the best practices are, etc. And that process moves really, really slowly by design. To say that it's a glacially slow process is almost a little bit charitable. It just cannot keep up with the rate at which things are changing right now.
John B:But it's not just the satellites in the night sky that are having an effect on the world.
John B:They have to get to space somehow, and that means there are a lot more launches taking place, and launches involve exhaust from rockets that is contributing some things like black carbon to the atmosphere that has a climate warming effect.
John B:Those satellites have to come down when they're done, and there's a prospect now that we're looking at a future in which there are dozens of satellites coming back down to Earth every day to just replace the ones that are being launched, so that you have a more or less kind of steady state on the numbers. We don't know what happens when you put all of that metal into the upper atmosphere, as those satellites burn up when they reenter. From the astronomy standpoint, we might be able to figure out a way eventually to where we can sort of coexist with the satellites. It won't be ideal for us, but we're learning how to cope with it. And that says nothing about the other users of the night sky, especially people from marginalized groups like indigenous populations that have had nothing to do with this. They don't have a seat at the table right now, and so it remains this open question you know who owns space and who should make the decisions about how space is being used?
Bill M:Wow, that's a really that's a lot to take a new job. I guess people you know in general, when people think of who's going to use the night sky, who's going to use that low Earth orbit, it's usually from a commercial or military standpoint And because that's the way it's always been right. One of the things you mentioned about how many people are in a perpetual twilight, you know, here in cloudy nights it's usually it's white, so you have the LEDs that are reflecting upward and it's actually pretty bright on a cloudy night And you can tell because if you look outside you can see the reflection off the clouds once you ground and it actually makes it very much easier to see on a cloudy night than it is on a dark night. Man, there's a lot to unpack there. Caitlin, you have any thoughts?
Kaitlyn E:Yeah, i think you know another issue with the satellite's open space. That's going to be something that most people are never going to see because, like we said, they live in perpetual twilight. If they're never getting out and seeing in dark skies, it's not something they're ever going to notice, it's not going to affect their lives and probably they won't care about it.
Bill M:So, john, to clarify with all the objects coming back down, does this mean we have to walk around with helmets? Is it advisable to sit on your couch at night with a helmet? Do we need to put like shields on some kind of plating on top of our houses? How's that? What are your thoughts on that?
John B:I hope it doesn't come to that, bill. I mean, some of your listeners will probably, if they're of a certain vintage, they'll remember when Skylab came down over Australia in 1979 and there was a contest for who could retrieve the fragments and bring them back as soon as they won some money for doing it. I hope it doesn't come down to that. There will be more instances where objects survive reentry. Most of them are dumped into the oceans by design, and that's something that increasingly the operators and satellites have control over, so they don't have these absolutely uncontrolled random reentries that are dropping satellite pieces on people's houses.
John B:But of course now we're dumping junk into the oceans and sometimes those spacecraft parts have toxic substances that are part of their manufacture, and so it's a potential hazard for marine life. But to be honest, the thing that I'm mostly worried about is not even here on the ground. It's the increasing amount of junk that's orbiting the earth and all of the debris that is posing a risk to everything that's in orbit because of the high relative speeds between these objects that can be many thousands of miles an hour difference, where something as seemingly innocuous as a fleck of paint that comes off of a painted surface that impacts an object at thousands of miles an hour can leave a huge crater in metal because the energies are so high, and I'm really worried that, before this decade is out, that there's a strong risk of a loss of life accident in space resulting from a piece of space debris that hits a space station or a spacecraft that has humans on board. I think that day is coming and it will be sooner than we think.
Bill M:Wow, that's a very sobering and sad thought, john. But how about we move on? a little cheerier thought here about that. The travel front nothing's far from the sky, except for meteors right now. So just enjoy people and travel from. We stay in the land down under All. the reason is all the region is determined to keep its darkness as a stargazers dream.
Bill M:Chantel Francis of newscomau, the small town of Swam reach population 270, resides in southern Australia and received international dark sky reserve status over three years ago on a scale of darkness between zero and 22. The River Murray dark sky reserve at Swam reach measures a whopping 21.9. Tourism has become a growing business. The reserve hosts numerous telescope pads and offers offers tours of the night sky. There's an observant, there's hope for an observatory, hope for a planetarium. They have people moving into town because they want to have the property and be able to stargaze at night.
Bill M:Last month I asked the question whether nighttime is becoming a luxury. In this article, francis writes at least five avid astronomers purchased cabins within a reserve. The property, the reserve itself, is about an eight hour drive from Melbourne. Considering my five hour drive to get the dark skies here in Pennsylvania for cherry springs, that's not bad. That's like a week long vacation. You can make that work. A little bias here, though. Living on a bright I 95 corridor seems like only a select group of people ever get out to see stars, and it appears to be broken down by both income and identity. So my question you to how do we bring about opportunity for equitable access to night sky?
John B:I think you have to start by asking the question whether people are entitled to that, and there's a difference of opinion on it. Some people would say no, but the United Nations says yes. There have been two declarations issued by the United Nations Educational, scientific and Cultural Organization That is otherwise called UNESCO, one in 1994 and one in 2007 that called for a right to starlight, a right to access the night sky. And to just read a little bit of an excerpt of one of those declarations, the one from 2007. It says an unpolluted night sky that allows the enjoyment of the contemplation of the firmament should be considered an inalienable right of humankind, equivalent to all other environmental, social and cultural rights, but at the same time, right. We haven't even decided that living in a clean environment, in a safe world, is a human right. We haven't all decided that, and we live in an economic system that really doesn't prioritize that. Some people are working on that. As an aside, there's a whole movement to try to convey legal rights to nature itself, which otherwise can't defend itself against what humans are doing. But let's say for the moment that you accept the premise that there is some sort of right to starlight or that there should be. I think the best way that we can approach that is to write some laws around it. We can do that, and when we do, we still have to defend that As it is right now. Environmental groups sue the US government all the time to compel it to enforce environmental laws that are already on the books. But if we have a culture where people are more supportive of this idea and they recognize it as something that they want in their environment, i think it gets to be a little bit easier to to implement it like that. How do we do this?
John B:Bill, you mentioned earlier in one of the little excerpts in the articles about how light pollution is, i think, a social justice issue. We know from research that it affects people disproportionately, depending upon their economic status, their race, where they live. Organizations like the US National Park Service have been dealing with this for years. They really fret about the fact that you go to pick any of the big flagship US National Parks And the demographics of the visitors there don't really look like America. It's only a subset of people that are able to access that, and so I think not only do we need to work on light pollution in the near cities.
John B:Again, that's the main source of the problem And it reaches really far away from the source to affect these places. But also we need to figure out ways to improve access. How do we get kids from the inner city, from Philly, to go to a place like Cherry Springs? Are there ways that we can make that possible? I think there are, and for some of them it can be life changing. Just having the validation If you're a kid who's black or brown, from a low economic status and you get to go, experience that is a validation. I think that at some level you matter in this society because we want to share the best of what nature has to offer. And how can that not make us better as a society if we do it?
Kaitlyn E:Yeah, and this topic brings to mind one of the guests we had on a few episodes ago from the Philly Moon men. He sets up his telescope in the center city, brandon Hap.
Kaitlyn E:Brandon yep And he tries to show the moon and planets to people walking by. He sets up local neighborhood events And I think part of the issue of getting support behind initiatives like this is people don't know what they've already lost. You have generations growing up not knowing what a starry sky should look like, and if they don't know it's gone, why are they going to want to bring it back? They don't even know it should be back.
Bill M:Yeah, that's an excellent point. My big fear is that people just aren't going to know. And you go around, you live in a city where we live in a city, so it's a little it. You're a little biased because of your experience with the people around here. You expect people to have a certain perspective and to know what's up in the sky because you're going to see. You know like 35 stars, right, so why would they be curious? But I think to your point, john man, you can. If there's a way to get kids to just be able to see, hey, it does exist. It's not something on a in a planetarium, it's not something you know in a video somewhere on Instagram or wherever. You could have one or two kids, change their lives. They could go down a different course in their life. They could become one of the great astrophysicists of all time. They could become that kid. I think they'll be an amazing feat.
John B:And you know, bill, even if they don't, it's the idea that that those of us that work in science communication really have it. our core is we're. you know, we're not necessarily trying to turn every kid into a scientist Although I I kind of think that every kid is naturally inclined to that but more like they grow up to become full members of our society right, they they're. they're voters, they're parents, they're consumers, and at every one of those steps they can apply the things that they've learned to make their lives better, to make their communities better.
John B:Something that we've been trying to do in dark skies for a long time, when we're able to get people into these places, or even if we're just showing them what good lighting looks like in an urban context, is to get them to to think about that and take away this idea that could exist where I live You know why aren't we doing it like this in my neighborhood? And if we can just get those ideas in their heads that they can create that change. And to Kayoan's very excellent point, it can be hard to do that if they don't know what they're missing. It can be hard to get that support for something that they've never had regular access to. If we can figure out how to get over that, i have a lot of optimism that the situation is going to start to get better.
Bill M:Yeah, and they, they can. to your, to your earlier point, that they don't have to be scientists. They can be just to to have a better perspective on a world, or be artists there's whatever you want. The night sky for me is always, it's always inspired me. I've always felt better after looking at the night sky. So, hopefully, maybe, maybe that doesn't work for everyone, i don't know, but that's me. So we'll begin to wrap up here. We have one little quick hits area and then we'll we'll finish up with our Friday the dark segment. So how about we jump in before we get to the big enchilada?
Bill M:the the best smart lights for the outdoors in 2023, brittany Vincent of CBS, essential. Oh, there's a lot to not love here, but it does fall in line with last month's lumens are coming article. For those of you who feel the need to light your trees, because we need to light our trees at night, i guess this article features spotlights that can be programmed to over 16 million colors. I did not know that there were 16 million colors, including lucky for all of us all shades of white, thank God. That, which you can also do for 500 lumen floodlight set. So spotlights, floodlight sets, it's great. And hey ring has a new solar path lighting. Don't worry about the fixtures themselves. Put out up to 80 lumens of sideways light because the light is not coming down from the top of the LED fixture. So you know, it's astounding when you look at some of these pictures, the amount of redundant lighting that people have. I don't know, it just doesn't make much sense. Yeah, lumens are coming. Whatever people want to light up, they're going to find a way. I guess Next up is the LDS church.
Bill M:We'll get the light up. It's Hebrew Valley Temple, and this comes from some Blake Apgar of the Salt Lake Tribune. The Church of Jesus Christ of Latter-day Saints fought hard to rid itself of any nighttime lighting responsibility by pressuring Walsh County, utah officials to approve new lighting rules which would enable the church to light a proposed new temple the same way it does pretty much every other one of its temples. The church received permission to uplight the temple, enabling an exception to be made in Walsh Church's rather strict, rather stringent nighttime lighting rulebook. However, the temple will be restricted by the level of lumens it can use and it must have exterior lighting turned off an hour after sunset or an hour after normal business hours.
Bill M:We have smart street lights. Smart street lights market is expected to rise to 14 million in the coming seven years, and this is just a market research press release. The pandemic is officially over, but smart street lighting is about to boom. So combine and rush to LED fixtures with the Internet of Things and expect to see street lights moonlighting us traffic and parking monitors, air quality meters and, i'm sure, many more things. Not to mention, it's anticipated that camera connected smart street lighting will increase road safety by lowering the likelihood of accidents and criminality. I'm not really sure how that's going to work, but hey, texas now has seven dark sky communities for spectacular stargazing.
Bill M:Saina, amir from MRT, this cheer on the city of B cave. Everyone I know. Michael was on here last month talking about B cave. B cave is now a member of a growing list of dark sky places already in a lone star state, including two dark sky sanctuaries, five dark sky parks and one dark sky reserve. Nighttime is alive and well, at least in some parts of Texas. John, how do you feel about, about B cave? This is? I feel like Texas is just racking them up right now.
John B:They are, bill and, and really you're setting a good example for the rest of the country. I actually had a little personal stake in that. I used to live in Austin, texas, which is quite close to B cave, and talk to them in the very, very earliest stages of their project, in around 2015 or so. So it was really gratifying to see them get over the finish line with that, because it is a very demanding set of requirements that one has to reach as a community in order to receive this accreditation from the IDA. So I'm thrilled for them and glad to see that they finally made it.
Bill M:And how often do they need to test to make sure light levels are correct for these different reserves? I guess in this case B cave is a community or the right Okay, So I guess how often do they need to retest that light level?
John B:Right. The dark sky communities, which are our cities and towns, are handled a bit differently from the other categories in the program. You mentioned in the description of the story that there were a couple of dark sky sanctuaries, five dark sky parks and a dark sky reserve recently named. It's the biggest one in the world, by the way. It's in West Texas. It's a huge amount of land that's been brought under protection For most of those categories.
John B:They do have to qualify based on the quality of their night skies, which they have to measure in order to make sure that it meets the IDA standard, And then they are obligated to do monitoring on at least an annual basis going forward so that we can see how things are changing and pick up on if there's any trouble spots in the area that need to be dealt with. The communities are a little bit different. They don't have a night sky quality requirement associated with them because the thinking is that any community, no matter how it starts off, could get better over time based on having good outdoor lighting policies and lighting practices. So they submit some measurements of their sky brightness when they apply, but it's not part of what qualifies them. It's more like watching to see in the future? does the conservation part of the program that applies to those communities does? it seem to change the brightness of their night sky over time, And there's a little bit of data we have on that that suggests that it actually does Interesting.
Bill M:We'll be looking to see what happens with B-Cave. Well, congratulations to B-Cave. So we have the afraid of dark coming up next. before we get to that, i did want to tell us a ball back to you, john, real fast. How can people find out about what you're doing, or how can they follow you, or where can they find out more?
John B:People can visit my website, which is wwwdarkskyconsultingcom. That's all one word. I have a blog on there right about stories every month that are of interest to people who follow this kind of thing. I'm on Twitter every day at John Berentine. You can finally find me on Mastodon if you search on my name. The handle is too long to mention, and happy to talk to anybody about this issue. It's my favorite thing in the world And I'll talk to your ear off if you give me the opportunity.
Bill M:And you might have picked up on it. You jumped to Mastodon. Honestly, you have no faith in Twitter. Is that what you're saying?
John B:I'm one of those kind of holdouts that's doing both right now. It's been an interesting experience over there because it's a bit different as a platform. I think they're kind of complementary in certain ways, so I try to be active on both.
Bill M:Oh great Caitlin, anything new coming down on Instagram. What have you got going on?
Kaitlyn E:I'm just going to be posting some highlights from the stories that we've discussed and links to all of our articles and show notes.
Bill M:Okay, well, that's nice and concise. One last thank you to you at home. You make everything we're doing here really worth it. Feel free to reach out to connect with me Bill had light pollution news or you can join in conversation, as we mentioned before, over Reddit on light pollution news, and you can see all the lists of these links over there. So, quick, stop by if you want to check to see anything we talked about here. You can just go there and grab that link and check it out for yourself. Additionally, stop on by to the website for show notes and details and every show we've done, including lighting tips and much more.
Bill M:So how about we jump into it? Let's get into the Afraid of Dark and wrap up with our featured research article. Our Afraid of Dark article is a bit scary. Hilton heads, dark roads and pedestrians are deadly combo. What the town is doing about. This comes from Blake Douglas over at the Island packet Pretty article.
Bill M:Nine pedestrian and cyclist fatalities occurred in 2018, with five occurring after dark. Prior to that period, there were 28 recorded deaths from 2000 to 2016, with 20 of them taking place after dark. In 2018, an 11 year old resident was struck and killed while walking her dog across the intersection. One night, lighting advocates began taking shape. And what otherwise is a very conservation focused island, hilton head, south Carolina, has a limited number of street lights, providing itself on avoiding light pollution and blending nature with construction. Lighting advocates appear to be, at the very least, asking for flashing crosswalk lights on the island to indicate when an individual is crossing.
Bill M:It should be noted that the article shows a chart of nine after dark deaths since 2014. Only two of them occurred at crosswalks. In fact, during the same time frame, six additional deaths occurred at crosswalks during the daytime. As a whole, national Safety Council reports that 74.5% of pedestrian deaths occurred at night, whereby 39.1 of them took place in lit areas and 35.38 took place in on that areas. Alright, so Brian Blotch, an auto safety expert, thinks that, hey, you know what car companies might actually bear some of the blame in this, because they're producing cheaper, ineffectual headlight fixtures and the drivers themselves don't realize they might actually actually clean their headlights. Despite hearing opposition from residents in Hilton Head on new lighting fixtures or new street lighting, it appears that Hilton Head will be receiving lights at two new intersections and possibly more, depending on engineering studies that are currently in progress. So my question here is lighting really the key variable here? More light actually going to solve pedestrian deaths, yeah.
Kaitlyn E:Well, at least in some of these cases. They mentioned one of the main roads, 278. It sounds like speed could certainly be a factor, because they were saying the average speed limit is 45 to 55 miles per hour. And I mean even crossing that in daylight I think would be a bit of a risky endeavor, just judging with that kind of speed. So you know, i think that probably plays a factor in at least some of these issues And I'm sure putting in the flashing walking signs would definitely help to alert drivers from a ways off, like you know. Hey, you might want to slow down a little bit here and that could potentially mitigate some of these issues.
Bill M:Yeah, this is a tough one. This is really tough one because to me it feels like they're pitting light as a bad guy here, in which there's more to the story And it could be road engineering. You know, there's a lot that goes into to pedestrian deaths at night. It's not just light, there's many different variables on the driver's end as well, and this article wanted to frame everything on the fact that light was the blame for having pedestrian accidents, which actually made up, you know, a piece of the total puzzle. But it wasn't the pedestrian accidents at night, wasn't the whole story? There's a equally weird daytime issues going on. So to me this I don't know about you guys To me this felt unfairly. Looking at light, i think there's some great things in there. Right, have a crosswalk lighting? Sure, why not? I mean, what harm could that do? But yeah, it's wondering any thoughts on your end, on either of yours. You know how is that right? Is lighting being unfairly targeted here? I?
John B:think they're probably playing it up beyond what can be justified with the facts, Bill, to be honest. I mean, we have a lot of research on this over many decades and it's very clear that where traffic comes into what they call conflicts, or you have intersecting vehicle traffic or bicyclists or pedestrians that are crossing roads, adding light in certain amounts saves lives. There's absolutely no doubt about that And we would never say that, oh no, you have to take that lighting out because of dark sky concerns. Could it be made better? Probably. I think a place is like maybe not so much in Hilton Head, but we talked about sea turtles earlier and places like the Florida coast where you would have these lighting installations near beaches that were the sea turtle presence as a problem. As far as that goes, You could imagine very well designed lighting that would provide the light that's needed to ensure safety at a crosswalk but didn't intrude onto a beach. People don't put those things together very often, so they just think, well, we just need to make it brighter, And if we make it brighter it'll be more safe. And there's a bit of reciprocity failure in that, because once things become very bright, the glare factor associated with that lighting can be equally dangerous as no light at all.
John B:There's also a little bit of other research on this that looked at the influence of car headlights, which are the light sources that all cars take with them everywhere, right, And how often are their accidents happening in places where it's dark other than headlighting? And, in particular, how does that work as a function of speed, If we're talking about barely low speeds below roughly 35 miles an hour? The research on this suggests that your headlights are better at showing drivers obstacles in the roads than continuous overhead lighting is, So let that sink in for a minute. If that's true and there's good reason to believe that it is then it means that if your speed limits are that low and people aren't driving faster than that speed limit on a routine basis, which traffic law enforcement can really put a dent in that? if law enforcement commits to it that you don't need overhead lighting at all to do the best job, which is with those headlights And interventions like the lit crossings, like the flashing lights.
John B:My city here, Tucson, Arizona, has kind of pioneered this recently with what are called hawk crossings, HAWK. We were one of the first cities in the United States to put these up at midpoints between intersections, because we have a lot of fatalities related to jaywalking And our lights are not as bright as they are in other cities because our city is very conscientious about that And in places where they have put in hawk crossings that have lights that not only flash but they go solid red So drivers have to legally stop as if it were a red light. In an intersection where they have put those in, fatalities have just absolutely plummeted. So a combination of good lighting design, certain kinds of traffic signal interventions and relying on headlights to do what they do best, I think is the key to solving this problem.
Bill M:Yeah, wow, that's, that's impressive Hawk lights. Okay, yeah, i don't know if anything will make the driver stop around here, but we give it a try, man, that'd be nice. Yeah, it definitely felt like we're trying to blame everything on light. And I think to your point, john. You're not saying no light, you're saying just be, recognize what actually are the drivers of the issue and address those.
John B:Yes, strategically strategic placement of light in the right amounts, right times, right places. That's what we know works.
Bill M:Well, let's jump into our featured article, shall we? This comes to us from animal conservation. Manipulating spectra of artificial light affects movement patterns of bats along ecological corridors, so bats are already known to have a wide range of responses to artificial light. Fast flying species tend to be more opportunistic, while slower ones tend to be more light of verse. We know that long wavelengths and reduced intensity can minimize the environmental effects on bats. It's not unheard of for bats to travel upwards of tens of kilometers per night And furthermore, bats are very dependent on the landscape and the structures within those landscapes. Despite the nuances between the species, the consensus that artificial light at night, especially high intensity artificial light at night, negatively affects bats, and this study attempted to answer what exactly bats do when they encounter Alan. How do they react depending on different types of Alan? So the study uses three different types of light fixtures, one green, one red and one white, the control being devoid of any light.
Bill M:The researchers attempted to ascertain the behavior of bats as they encountered lights adjacent to woody areas. Researchers looked at three different back groupings based on their foraging echolocation behavior, that being one of them being a field forager, the other being a forest edge forager and another one narrow space, or, more aptly, a forest foragers. Researchers found that open and edge foraging bats increased their activity when they were close to white and green lights and lesser around red lights. However, narrow space bats were more likely to veer away from all color of lighting. Edge foragers were also less likely to cross a white light, so the positive effects of white and green light on open and edge foraging bats may be attributed to the accumulation of insects around those light sources containing more of the blue light. It just feels like another article really showcasing ecological impact of nighttime lighting. John, i know you have some thoughts on this one.
John B:Yeah, what this says to me, bill, is it reinforces the notion that there is no source of light out there that is is wildlife friendly, although you will see that sometimes applied to certain colors of light or types of lighting, even in the sales literature of lighting companies. So they'll have. For example, they have the sea turtle lights on the Florida coast that are an orange color to which the turtles are less sensitive than other wavelengths. It doesn't mean that they don't see that light, they just react somewhat less to it. I think we tend to with these problems, we go to this notion that technology is always going to save us, that somebody will come up with some sort of technology and it will just it'll solve this problem in a way that we can just put more and more light up and we sort of wash our hands of the issue because we think, oh well, it doesn't affect that species. And it's true.
John B:There's other papers that suggest that a lot of bat species are relatively insensitive to red light, to the extent that there are some communities in Europe that are starting to put up red street lighting in very specific locations in cities and towns that are known to be corridors that bats, as they say, commute along, But as soon as you put up these really red lights they're really red lights, yes, and just limited use trying to keep these corridors open so that the bats can still move freely at night. They won't be drawn off of their. They're foraging routes. But as soon as you put up a light that the bats aren't sensitive to, there's some other species out there in the vicinity that is. And now you have this unintended consequence where now you've conveyed a disadvantage to some species that you weren't even thinking about before.
John B:Pretty much every species that we've studied shows a reaction to artificial light at night And, as we were talking about earlier, it piles on top of these other stressors that they're under. So I think that for as much as yeah, let's figure out, you know where can we use light in creative ways that have less of an impact on species? We have to be mindful that there's just no magic bullet out there that is going to solve the problem. We have to come back to this notion of trying to reduce the overall amount of light that we're putting out there into the world to begin with, and then worry about these additional effects, like what color it is.
Kaitlyn E:Yeah, and to go along with what you're saying, like you know, we can't just add more technology, more different kinds of lights to, you know, work our way out of this, like a point they made in the article is just the mere presence of light can affect the habitat availability of bats And so, like we can't change your light, we can't modify it, just the actual presence is going to affect the habitat availability which, you know, like all animal habitat availability is getting smaller and more fragmented, and this is just another way we're decreasing that habitat and fragmenting it even more.
Bill M:Yeah, without a doubt, John. if I'm a homeowner and I want to be ecologically friendly with my lighting, what should I do?
John B:Number one really ask yourself whether the lighting is necessary in the first place. A lot of the sources that contribute to light pollution is lighting that really doesn't serve an identifiable purpose. Or if it does, let's say you want to light up halfway adjacent to your house. There are ways to put that lighting on timers, to use motion sensing switches and the like to limit the duration that it's on. So if you say, yes, i have a need because I need to you know, when I am out there at night, i need to be able to walk along the path. Okay, how can you then reduce the duration that the light is on?
John B:It's asking those kinds of questions, i think, first and foremost. And then, after you've kind of gone down through that list and, okay, yes, the light is necessary, and you know, yes, i've taken as many opportunities as possible to try to limit the impact of that light being there by limiting its duration or it's making sure that it's the right brightness, it's not too little and it's not too much. Then, after all of those things we would say in general to try to avoid bluer sources of light than other colors. It's not again, it's not a magic bullet, it's not, you know, something that doesn't affect any species if you use a red or a yellow light, but that blue light really affects a lot of species the most. So if you want to do right by the environment and about or by the wildlife that's in the vicinity of your home, try to choose sources that are warmer in color and have less of that blue component.
Bill M:I guess the actual the lumen effect has to be relatively mild.
John B:It does And it doesn't. The thing that is most recent to me is that in the studies that I've looked at, the effects of light on wildlife really start to set in at remarkably low numbers. Oh, lower than we thought before. Yes, the benchmark is, and because everybody can visualize this think about how bright full moonlight is And the numbers aren't important, but just think about being outside on a night with a full moon and roughly how bright that light is We see effects that we can measure in wildlife species down to less than 10% of that. Wow, so it does not take much light to produce a measurable effect that's harmful to wildlife.
Bill M:Well, well, how about green light? So, before we close up today, do you live in Hawaii? I know, i definitely wish I did, but if so, do you recall seeing a green laser streak across the night sky? Well, the Army Corps of Engineers was actually using LiDAR at night to complete a coastal mapping survey. So, don't worry, it wasn't aliens not this time at least But the survey was done at night because there was just literally too much air traffic during the daytime to do it during the day. So, hey, you know green lights, i'll know, i don't know. So that's all we have this month, folks. I really appreciate everyone sticking with us.
Bill M:I want to thank my guests, john Barantine and Caitlin Evans. What a great discussion. This was really educational, really great way to chat and discuss some of these ideas, and I really dive into different topics around light pollution. I want to thank you at home for listening. Again, if you're a fan of the show, you like what we're doing, please help spread the word Show the show with friends, because five star rating review or four star, I don't really care, just give us a rating and review. Hey, for the price of a cup of Joe, you can keep us shining the just enough lumens and I guess emotion sensing light, as John has mentioned, just where's needed.
Bill M:So check out support page light pollution news comm slash support And you can find all these links and more over at light pollution news comm. John, it's been so good to have you here. I have really, really enjoyed all the knowledge and the wealth of information you have shared with us today. Caitlin, always, always a pleasure. So finally, friends, i'm Bill McKinney with LPM. I'm very glad that you could join us. Look forward to seeing you next month and have a great month everyone.