This Week in Space 123 Transcript

Please be advised this transcript is AI-generated and may not be word for word. Time codes refer to the approximate times in the ad-supported version of the show.

00:00 - Rod Pyle (Host)
On today's episode of this Week in Space, we're talking about the upcoming meteor shower, the biggest, the baddest and best of them all the Perseids. Stay with us. Podcasts, you love.

00:13 - Steve Fentress (Guest)
From people you trust. This is TORQED.

00:18 - Rod Pyle (Host)
This is this Week in Space, episode number 123, recorded on August 9th 2024, the Mighty Perseid Meteor Shower. Hello everyone, and welcome to another this Week in Space, what I like to call the Mighty Perseid's edition. I'm Rod Pyle, editor-in-chief of Bad Aster Magazine, and I'm here with my good pal, isaac Arthur of the Science and Futurism with Isaac Arthur YouTube channel, which is very successful. How are you, isaac?

00:47 - Isaac Arthur (Co-host)
Doing great. Glad to be back on for Talk About Meteor Shadows.

00:50 - Rod Pyle (Host)
Thank you, and don't worry, you'll be on many more times. And today we have the pleasure of being joined by my old friend Steve Fentress, astronomer, physicist and recently retired planetarium director of many, many, many three decades. How are you, steve?

01:06 - Steve Fentress (Guest)
That's true, and it's strange to be exchanging emails to set up a Zoom call. I haven't done that for seven months. It's weird.

01:16 - Rod Pyle (Host)
Well, don't get used to being off, because we're going to have you back over and over Before we forget. I'd like to remind you to please don't forget to do us a solid Make sure to like, subscribe and all the other groovy podcast things that we asked you to do, because we're counting on you. And now, drum roll, a space joke from listener Jim, for whom I do not have a last name. Okay, I apologize as ants for this one. This is a boomer joke for sure. Why did Boeing's lawyers make them change the name to starliner isaac?

01:48 - Isaac Arthur (Co-host)
I don't know why did boeing change the name to starliner?

01:51 - Rod Pyle (Host)
because they found out edsel had already been taken.

01:56 - Isaac Arthur (Co-host)
Okay, um, anybody else got one uh, what did the meteor say to Earth? Hello Earth, can I crash at your place?

02:11 - Rod Pyle (Host)
Ah, I like that one better.

02:13 - Steve Fentress (Guest)
Steve. So there is a story that we used to hear that a college student was taking an astronomy class and the professor put a question on the test Could you define what a meteor is? And he wrote a meteor is a flash of light made by a falling meteorite, usually is seen at night. And I hope to God this answer is right, and it was, and the professor did give him full credit for it.

02:40 - Rod Pyle (Host)
That's definitely a planetarium story.

02:42 - Steve Fentress (Guest)
It certainly is. It goes way back, and you know how far back it goes.

02:45 - Rod Pyle (Host)
Yes, I do, because I was there. Well, I've heard that some people start chewing on their old gym socks when it's joke time on this show. But you audience can help Save the cosmos from us and send us your best work, best, worst or most indifferent space joke to twist at twittv, that's T-W-I-S at twittv, that's TWIS at twittv, and we'll be on our way. All right, we've got a lot to cover today, but I do want to do one headline because well, because, starliner. Our email has been full of conversation about this, as are the various online forums that I monitor. Lots of experts, or experts with finger quotes, depending on who it is you're talking to. On both sides of this discussion, this is polarized as the election bottom line, whether it's fair to criticize it or not. No matter how you slice it, starliner does not work as advertised. Whether or not Boeing can and will fix it and or move forward with the program is an open question.

03:43
Some of these sites I monitor. The folks listen to the press conferences and then everybody draws their different conclusions. The most recent NASA press conference was a real study in confusion. There was a lot of talk about the team's doing great. Our teams are wonderful, teamwork, teamwork, teamwork, and the problem is that doesn't tell us members of the media, anything, and that's who these things are supposed to be for. And a lot of these armchair quarterbacks rant and rave about the mainstream media doesn't get it and we're not listening and we're not paying attention and we don't understand how hard it is to fly in space and all that. Actually, a lot of us do. We've been doing this for years. Some of us even went to school for it, and the problem is not so much how we interpret the press conference. So there are media outlets like USA Today that have a pretty, pretty light dive when it comes to this stuff, but for sites like Ars Technica and Spaceflight Today and others, they really do work hard at it, and the problem is there's been a real lack of clarity from NASA and Boeing in these press conferences, and the last one was probably, as much as I love NASA and their media department, one of the I don't want to say worst, more challenging pressers that I've attended in a really long time, and they've been as fuzzy as a patch of mold about this whole thing. As I said, lots of remarks about the great team and validating data and so forth, but that only gets you so far. It's their job, nasa's and Boeing's, to be straight with and comprehensible by the media and while I know it's a burst bubble to many people who have criticisms of how we're doing our job, there are a lot of smart people I'm here, joined by two of them, particularly Isaac, who's definitely a high tent pole in space media, and even engineers in this field. So you know we got to continue to call it as we see it until we get something a little clearer from these guys.

05:38
There was an article on the bite, which is not exactly a high watermark of journalism, but they did a recent article on Starliner that cited some reputable sources and made one think.

05:50
A quote unnamed but reputable source with NASA allegedly said it was 50-50 that Sonny and Butch would come home in a SpaceX Crew Dragon at this point. As we probably all know, nasa contracted SpaceX to study doing just that and other emergency return options on July 14th for about a quarter million dollars, which is cheap by space standards, and you know we got Starliner sitting up there waiting to be used or not, costing almost double what the SpaceX Crew Dragon did in terms of the original contract and Boeing rapidly approaching $2 billion in the hole on the program, with no end of troubles in sight. So one wonders if Boeing will even continue this once they get their capsule back, with or without a crew. It looks like SpaceX could be the sole provider for a while, and of course the whole point of having two contractors is if one system packs up, you've got another to take people up and get them home. But at this point that other would be the Soyuz, and that's not what everybody wants. But there we go. Any comments from the peanut gallery, gentlemen?

06:58 - Isaac Arthur (Co-host)
I would say again, I've been trying to be as optimistic and favorable towards Boeing as possible on this one. I'm still glad there's folks besides just spacex in there, because it's good to have competition. But I think the kindest thing we can say at this point in time has been that, um well, needs done a bit of a disappointment. And again, this is from an industry where actually crashing your probe can at times be considered a success. So the bar is not necessarily that high for getting success, because we know how hard it is. It really is hard, and this doesn't mean they're bad engineers, they don't have to build stuff, it's.

07:34 - Rod Pyle (Host)
But at the same time this one has got to be labeled at best a failure, you know well, what's a bit of a head scratcher to me is, you know again, some of these, the, the broad audience pundits, to say well, you know, space spacex had longer to work out the problems of their capsule, although their problems in flight were never quite this, this impactful, as I recall, and there's some truth to that. However, boeing, which which absorbed McDonnell Douglas and absorbed Aerojet and Rocketdyne and absorbed North American aviation, most remarkably has a lot of institutional history. Now, how many of those people are, there is another conversation how many of them remain. But there is institutional knowledge, there's a lot of practice. They've been working on the space program since the late 50s, so it's not like they're a newcomer. They're scratching their head over gee, how do we make this work so?

08:32 - Isaac Arthur (Co-host)
yeah, they've got the institutional knowledge there. They got the equipment, the supplies, the funding, the background. It's just. This one has gone very poorly, as to why, like an autopsy afterwards, it doesn't look good, of course.

08:49 - Rod Pyle (Host)
And they're going to have to work hard, I think, to restore any confidence in Starline at this point, Steve from your viewpoint?

08:54 - Steve Fentress (Guest)
what's your perception of this whole thing? A couple of things I can remember being taught as a child. One of the big differences between the American space program and the Soviet space program is that the American program is done in the open, whatever happens, everybody gets to see it, and the Soviet program is success stories after the mission is done, if that's how it comes out. And NASA has gone from. Nasa PR has gone from being kind of reluctantly granting information to people other than the big three networks to becoming kind of an aggressive PR operation. I remember that from my days in the planetarium business and I appreciated your comment last week or the week before about how every NASA launch telecast includes a slogan, a commercial, right after launch. Yeah, and when I was working at the planetarium I kept looking for clean versions of those videos that didn't have that. It reminded me of what I read somewhere about people yelling mashed potatoes right after Tiger Woods hits a drive, so their voice would be on the video. So yes, it's hard, it's technically difficult.

10:12 - Rod Pyle (Host)
It's organizationally difficult, but. But if we're getting just happy news from NASA PR, then that becomes suspicious program, when they just cited facts and told you how it was and there was not. For instance, when Apollo 13, the Apollo 13 accident occurred, which was a big deal, much worse than this, because those guys were stuck in there. They didn't hold back much, they were pretty straight up, straight ahead and announced things as they had them. So that's what I'm used to. But no, no use pining about that. All right, well, we're going to go to a quick break and we'll be right back and then it's all. Steve, all the time, stay with us, okay, steve? Hello, hi, I now have proof that you actually listened to the podcast. I appreciate that. Give us a refresher on your background for people who may not have heard you before.

11:01 - Steve Fentress (Guest)
Well, seven months ago I retired after 28 years as the director of the planetarium in Rochester, new York. A great honor to be there, and the new guy who has taken over, jim Bader, is very well qualified and I'm sure he's doing a great job. But I made a point of saying I was going to disappear and stay out of the way. My formative years were back in Southern California working at Griffith Observatory where you did, and also a couple of summers at the Jet Propulsion Laboratory as a temporary audiovisual technician in the Von Karman Auditorium during the Viking Mars landing press conferences. So that really shaped my experience.

11:45 - Rod Pyle (Host)
Yeah, I remember being very envious of you when you had gotten that job there. Didn't realize the time you were sorting slides, but it sounded like heaven.

12:03 - Steve Fentress (Guest)
It was a lot of hurry up and wait of the hottest parking lot at jpl, a rented trailer where they had taken every educational publication that was they didn't have any use for and thrown it in there for the last 10 years and my job was to go out there and organize that trailer.

12:20
So it's like 110 degrees outside the trailer and I'm in there. But I was fascinated because I got to read all this stuff. Uh, the 16 millimeter film library. I was in charge of that, you know, splicing the films and stuff. So I watched all the nasa movies. So there were exciting things, like the press conferences and seeing the first picture from the of the foot pad of Viking one on Mars, but also a lot of the tedious stuff.

12:49 - Rod Pyle (Host)
I had to sneak into JPL or to Caltech auditorium to see that first shot coming back from Viking, which in a way I mean I really wanted to be up at JPL but mere civilians like myself weren't invited. Nor actually were we invited to Caltech. I had to go in the back way. But it was fun being with the, with the press people, when the first picture comes back and it's a foot pad and they're looking around like why are we looking at a foot pad? Where's the horizon? Where's that great shot of mars? But that came in next.

13:16 - Steve Fentress (Guest)
So yeah, but that was the very first one and there was nothing on the picture with no legs or green eyes or anything like that, and no one knew at that point whether there would be.

13:27 - Isaac Arthur (Co-host)
So I just have to ask, all the years you've been running the planetarium, what would you say the biggest crowd, please, was? What show did they always like the most?

13:36 - Steve Fentress (Guest)
Oh, it's all over the place, and one of the things I think I'm proudest of of the Strassenberg Planetarium is that we turned it into a very flexible, respected, well-liked community asset. So there's everything going on in there, from Taylor Swift laser to astrophysics lectures to scout programs. A couple of things that really stick out in my mind were current events programs we did for the Voyager 2 Neptune encounter and for the Shoemaker-Levy 9 impact on Jupiter back when satellite television and the internet were new, and we would run those, updating them daily, and run them several evenings in a row and the phone just wouldn't stop ringing. That was very satisfying. And then toward the end I really enjoyed doing homeschool astronomy programs with middle school age kids. I think I have a soft spot for that age because you know things are just starting to really click and it's exciting to be in on that phase of somebody's life and show them all this neat stuff we have in astronomy and space.

14:47 - Rod Pyle (Host)
Before I forget, I want to remind people that Steve has a book out which is available on Amazon, as well as other outlets, called Sky to Space, with a subtitle. That's so long I can never remember it, but give us a quick blurb on that if you would.

14:59 - Steve Fentress (Guest)
Yeah, sky to Space, astronomy Beyond the Basics, with Comparisons, ratios and Proportions. So the idea here this was really made to lead up to the April 8th eclipse, but it still has a lot of good stuff in it and the theme is using like fourth grade math how far in the universe can you get in understanding what's out there and what we can see? And the answer is pretty far. So a lot of the book is about predicting eclipses, but there's also things on the apparent size of the moon. We analyzed Chesley Bonestell's famous painting of Saturn as seen from Titan. You know and reverse engineer how he figured out how large to make Saturn in the sky, exoplanet systems, things like that. So it's still out there and you have to update it for whatever your next eclipse will be. But the basic astronomy is still good so is your.

15:52 - Rod Pyle (Host)
Is your experience similar to mine that you're not yet making a living just off that book title?

15:57 - Steve Fentress (Guest)
that would be similar. Yes, although there was a little bump last time I was on this show and mentioned it. So thanks, rod fantastic.

16:05 - Rod Pyle (Host)
It's a great book. It really is fun. And, by the way, besides, uh, the planetarium work and astronomy and so forth, steve is also a gifted artist and musician, and while the music didn't play a part in that book, um, certainly the artwork is impressive. I I had not realized when you first told me about it that it was going to be not just filled with your drawings of things to explain everything, but even with your ability to still write with your hands, which is something that I lost a long time ago.

16:36 - Steve Fentress (Guest)
Very impressive 160 hand-drawn pages.

16:40 - Rod Pyle (Host)
There you go and done. Well, isaac, sorry, go ahead.

16:45 - Isaac Arthur (Co-host)
When the Eclipse came out, he had come right into my area to see it. We were just right down the road from my house there. We had a magnificent view of that in April, so the eclipse for a lot of us is one of those events that was a once-in-a-lifetime chance to go see something really amazing right from your own backyard. Right from your own backyard and I've seen a lot of ways. That kind of leads to our topic for today of the meteor showers, because that is another one of those things you just lay out in your backyard and see without telescopes, without anything, just with the naked eye and with less pressure about time and location, with meteors as well oh my god.

17:18 - Rod Pyle (Host)
Yeah, I, as a kid, I used to be able to sit out. We had a back patio of our house in pasadena, california, which is not exactly rural, but I can still see stuff these days. I still live in the same area and I go outside and there's just the sky is just this big orange wash with three or four stars poking through. So things have changed.

17:37 - Isaac Arthur (Co-host)
It's getting harder and harder to find good dark skies I hear that anecdote going in for the eclipses because I have the freeway lighting coming off from both sides of my south and my west side. So when the uh a lot not very good night viewing, but when the eclipse came the lighting actually all turned out on the freeway. It was kind of neat. So but yeah, it's not not easy to find a good place to do a lot of nighttime watching anymore, even in rural areas all right.

18:01 - Rod Pyle (Host)
well, we're going to talk a little bit more about that, and we actually are going to talk about the Perseids, and we'll be back right after this short break. Stand by, all right, steve. Tell us about the Perseid meteor shower and why it's going to be special this year.

18:16 - Steve Fentress (Guest)
Well, every year at this time around August 12th we have extra meteors appearing in the sky and this particular event is called in the trade the Perseid meteor shower, and at its peak activity you'll see maybe a meteor every minute or so if you have a dark location and can watch a lot of the sky and you'll see it all. It's already all over the media and every website and every newspaper. It's a very happy story to be able to put up there something that you know is going to happen. This year is special because, first, the moon will be out of the way the moon sets around midnight, so you won't have moonlight washing out meteors and second, we've got two planets, jupiter and Mars, appearing very close together in a sky that's a part of the sky that's already spectacularly filled with bright stars the Taurus-Orion region. So, starting about three o'clock in the morning, the eastern sky is going to be just beautiful even before you get to the meteors.

19:15
So peak activity is expected late morning, north American time, on Monday. I would recommend this is more of a get up early thing than a stay up late thing. I would get up about three o'clock in the morning on Monday or three o'clock in the morning on Tuesday and watch till dawn if you can. Even if there are very few meteors, just for the two planets and all these bright stars, it's going to be a beautiful sky. So I've been calling this the second best sky event of 2024, after the eclipse, because you have such such a nice combination of things going on well, it's definitely a very cheerful event.

19:53 - Isaac Arthur (Co-host)
Without you know, it's not a good use year for people to have something that's just happy to talk about, and nothing's quite so happy as having thousands of rocks hit the planet, but they're actually. They're not really all that big all that we tend to think like, especially shimako Levy. That thing was huge, even dinosaur huge, but how big is the typical meteor that we're going to be seeing on this upcoming weekend?

20:13 - Steve Fentress (Guest)
The analysis indicates that most of the particles that make a meteor shower, like the regular meteor showers that recur at various times of year, these are little particles from comets and they range from microscopic up to a few millimeters in size, and they are crumbly comet material. They're not pieces of solid rock or metal, except for one shower, a different one, that may be caused by pieces of an asteroid, but that's a whole other topic. So it's not actually rocks falling out of the sky and if we have time for that, we can get into that, because everybody in the planetarium business knows that that right after the Perseid meteor shower is a more than likely time to receive a phone call from somebody who has a strange rock and wants to know if it's a meteorite.

20:58 - Rod Pyle (Host)
Which, of course, if you're in the planetarium business as we remember from Griffith, particularly being up on top of the hill which all los angeles can see they call you with just about every weird question they could think of. My favorite of which, which I've related before, was uh hi, is this griffith observatory? Yes, are you an astronomer? Yeah, sure, uh, I found a frog on hollywood boulevard. What should I do with it? I thought now that that is an intuitive leap, for sure.

21:23 - Steve Fentress (Guest)
Um, you know, my interpretation of that is at least they have enough respect for the institution to think you might know. At least you're a community resource. You know, even if the question is not quite what you say, you're in for. I had the privilege of being the banquet speaker at a Planetarium Association convention a couple of years ago and as a warm-up at the beginning of the talk, this was about 75 people in the room, many centuries of combined planetarium experience, and so I asked by a show of hands, how many people have had a call at your planetarium from somebody who has a rock and wants to know if it's a meteorite? Every hand went up. Second question in how many cases was there even a slight chance that this actually was a meteorite based on what you heard or saw? One hand went up. So it's actually. It's very. People find strange rocks and it's. We love curiosity and we love the institution being respected as a resource, but your chance of finding a real meteorite is very small, the ceiling of that people's house in Florida.

22:42 - Rod Pyle (Host)
That one, probably, you know. You could safely say okay, that's probably something from the sky, although it turned out to be a piece of a space, of the space station, didn't it? Was it? I think so. So the I remember as a young man trying to figure out why meteor showers are better after midnight, and it occurred to me and I guess this is correct that that's because the Earth has turned and is now facing the direction that the rocks live in space, so they're hurtling in faster and, I suppose, at a higher frequency. And the way I always envisioned these things was in this case, the comet Swift Tuttle crosses the orbit of the Earth along the eclipcliptic, the equivalent of the solar system's equator, and leave behind this kind of trail of gravel, and that's what we're seeing every year. Is that the correct assessment?

23:32 - Steve Fentress (Guest)
yes, uh, the earth plows through this trail of stuff and and, uh, we can get into it if you want, when you have time, if you have time, the way the astronomers in the early 19th century figured this out. Just to get it started, there was a German astronomer way back in the early 1800s who was thinking about meteors and he said you know, if meteors, if these are made by particles from space, and if they're arranged at random in space and they're flying around at random in space, ranged at random in space and they're flying around at random in space, but if we see them coming in from some preferred direction, that could be a physical clue that the earth actually moves in space. As Galileo and Copernicus said it did. And at that time the only other physical proof that the earth moves was the so-called aberration of starlight, which had been measured very difficult measurement about 100 years before. And that's where light arrives at your telescope at a slight angle because of the Earth's motion through space. So stars appear very slightly displaced at different times of year. It's a really hard measurement, but up till then there was no other physical proof that the Earth actually moved.

24:45
It was just an idea that made a lot of sense and this guy came up with this idea. Maybe it would be good idea to watch meteors statistically and see if there's any trend beyond just total randomness, and that could be a clue about how the solar system is organized and how things are moving. And then it goes on from there and I can get into more of that in the next few minutes. But I think it's great because it's this low tech observation. It doesn't involve super duper, badass telescopes or high resolution clocks. It involves a lot of people watching the sky and keeping records and then analyzing the records and you can get this profound insight about where we are in the universe and where we're going.

25:26
Long answer to a.

25:30 - Isaac Arthur (Co-host)
When I was running the observatory the small one we had at my university on Friday evenings we'd have some very interesting and strange questions come up. My favorite was can you point this thing at the sun right now? And of course it was about 10 o'clock at night and the person said it with a completely straight face. But the other one that came up that was a little bit less bad than we had I like that question we got a lot of times it was how do I take photographs?

25:55
And this was really early digital camera days. People started those little tiny early digital cameras and it was very different to try to do long exposure times for folks who are going to be watching this or might be setting a camera out at nighttime because they want to stay up for it. Is there any kind of good method going around, you know, photographing videos, any suggested advice for how do we actually keep this, you know, in our memories?

26:15 - Steve Fentress (Guest)
um, the key is to be lucky, which means to take a whole lot of exposure. So, um, there may be a way to do it with the software on your phone. Check around. I have an iphone se, so it's fairly simple. But I got great results from this 15 or 20 year old canon point and shoot s95.

26:34
What I do is put it on a tripod and then there's this software hacker software you can download that enables you to get extra control of the camera. Set it with an intervalometer function. Intervalometer automatically takes pictures over and over again until you tell it to stop. Set it to take 15 second exposures and just keep doing that until the memory card fills up or the battery dies or dawn comes and I stop it, and at the end you'll have several hundred pictures and you go through them and some of them will have meteors. So that's what has worked for me. It's basically, whatever your equipment, whatever you need to be watching a large part of the sky and have your shutter open as much of the time as possible, because you never know when a meteor is going to come. So you take a lot of pictures and then look for the good ones.

27:25 - Isaac Arthur (Co-host)
Kind of going back to the idea of these giant banks of gravel and space the comets leave behind. How long do those last? For Very long periods of time for us to go through. Or does that have to by the comet a lot? What's that actually look like?

27:38 - Steve Fentress (Guest)
well it it. They get refreshed every time the comet goes near the sun. So we we've come to understand that a comet is a dirty snowball, that it's frozen water and frozen carbon dioxide with a crust, or mixed in or with a crust of kind of dark carbon rich, crumbly material. And these things spend most of their time way, way, way, way far out in the solar system because they're on big elliptical orbits and in a very elongated elliptical orbit. You spend most of your time far out where it's very cold, very dark. We don't see them, but once in a while they come in near the sun. The sun heats up these ices, turns them to gases, so they blast through the dark crust, shoot jets of material, including dust, out into the trail of the comet.

28:25
And then the astronomer Giovanni Schiaparelli first figured this out in the 1800s If you have a blob of particles that whips around close to the sun, by the calculus of Newton's laws of gravity that blob of particles will spread out into a long stream along the orbit. So every time that stream goes around the sun it will get longer and longer. And if this happens these episodes of pieces breaking off the comet, if those happen multiple times, you'll have multiple streams and after a while they will extend all the way around the orbit. So, even though the comet may not be anywhere nearby, you may be cutting through one or more streams of material that it left behind.

29:13 - Rod Pyle (Host)
So interesting. You mentioned Schiaparelli, who of course is a little more nefariously known for having made copious observations of Mars and labeling, probably quite innocently, the lines he saw which may or may not have been the capillaries in his retinas reflected back in his eyepiece canal, which of course many, including Percival Lowell, translated into English as canals implying artificial creation and so forth. So we love Scaparrilli for that. All right, we are going to take a quick break and we'll be right back with more exciting news about the Perseids. Stand by, Steve. Tell us, if you would, how we can best observe this. You mentioned dark skies, but of course those are becoming harder and harder to find. There is a website I think it's called darkskyorg, if I remember correct where you can get more information on this, but if I'm in the middle of Pittsburgh or Los Angeles or New York City, I'm probably not going to see much right.

30:07 - Steve Fentress (Guest)
Well, my suggestion is find a place where other lights are out of your field of view, and that may be hard to do too. Leds have made light so cheap and, unfortunately, abundant. But if you can even just screen out the neighbor's porch light, so that your eyes have a chance to adjust, your pupils have a chance to enlarge, and then relax in a lounge chair, watch whatever part of the sky looks darkest to you, dress warmer than you think necessary, because meteor watching doesn't involve much physical activity and if it's a clear sky, you're looking at something that's at a temperature of three degrees above absolute zero, so it's sucking the heat right out of your body and just relax and watch as much of the sky as you can. As I said, if it's a good, strong meteor uh, perseid shower, it's an average roughly one or two meteors a minute. So, uh, not like a heavy rainstorm, but um, active enough to be interesting.

31:12
Have your favorite warm beverage if you like. If you have binoculars, bring them because you can look at other stuff in between meteors and just enjoy it. And, as I said, I would suggest, if you have to choose, it's more of a get up early thing than a stay up late thing, because the intensity of the Perseid shower increases as dawn approaches. So I would say 3 am to dawn is prime time, and that's what I've been doing is setting the alarm for about 3 or 3.30 and go outside.

31:46 - Isaac Arthur (Co-host)
You know, when I was first getting into astronomy as a little kid, I got to go see Halley's Comet come through at one of our local arboretums and I don't remember the comet at all, but I remember the advice I got from a guy about going into astronomy. I said what's the big thing you need to know to do it. And he said you need to dress warmly and bring hot chocolate and a thermos. And I was thinking there are a lot of other showers besides, you know, in August, so they might be very important to be wearing warmer clothing, more clothing. Are there any other really good meteor shower size the Perseids that are as reliable throughout this? Are we coming up for folks who missed this one?

32:17 - Steve Fentress (Guest)
Yeah, there are a number of relatively major meteor showers during the year. The other reliably good one is the Geminid meteor shower in December, definitely hot carpet and warm clothing.

32:32 - Isaac Arthur (Co-host)
Weather there.

32:33 - Steve Fentress (Guest)
Right, right, right, so it would be. I think the Perseids is the most popular one because it's a reliably fairly intense shower and in Northern Hemisphere the weather is nicer for being outside looking at the sky for three hours. But you have the Geminids in December and the Quadrantids in January. That can both be pretty good, but rarely do people talk about sitting out in lounge chairs for those. Then there are several others during the year Leonids in November, lyrids in April, eta Aquarids in May, and the American Meteor Society let me see if I can find my note here has a list of all the meteor showers that they have identified during the year. Here we go. So they've identified American Meteor Society. Amsmeteorsorg lists nine major meteor showers, including the Perseids and Leonids and Geminids and Quadrantids, 18 minor showers, eight variable meteor showers and 65 weak meteor showers, for a total of 100 over the course of the year and those weak ones. That's like one meteor per hour.

33:44 - Isaac Arthur (Co-host)
As a member of the family, that is a lot of space junk.

33:47 - Steve Fentress (Guest)
Yeah well, there are a lot of comets and a lot of particles flying around, but for these weak ones we're not encountering a whole lot. One meteor per hour per observer in ideal conditions. That's a lot less than 120 for the Perseids.

34:03 - Rod Pyle (Host)
So, just to cover all the bases, on any given night, if you're under a dark sky and the moon's not particularly bright or is down, you can see some meteors, which are called sporadics, as I recall. They're just out there, but can you talk a little bit about for these scheduled showers if you will, the idea of a radiant and why that's handy?

34:26 - Steve Fentress (Guest)
Well, you pushed my button because I'm going to tell you the historical version, because I find it fascinating. People were noticing. I thought the schedule of meteor showers like the Perseids and the Leonids and everything and the radiance had been known since ancient times, like Jupiter or the North Star. But no, it wasn't until the late 1700s people started noticing. You know, there are certain nights we have more meteors than usual. What's up with that?

34:58
Then an astronomer wrote to this famous Belgian mathematician, adolphe Quetelet, q-u-e-t-e-l-e-t, who's known as the father of statistics, and said you know, an interesting statistical problem would be how many meteors are there on an average night? So catalay actually created a network of observers in the early 1820s, set them out watching the sky and came up with a number an observer in a dark sky on average average average nothing special going on sees about eight meteors per hour, which is still a rate that's accepted today. But then there were a couple of heavy meteor showers that people noticed and got people's attention, and there were astronomers in America working on this, not communicating very well with other astronomers in Europe who were working on the same thing. Working on the same thing, and a thing that really tipped it off was a very heavy meteor shower in the Leonid Shower in November of 1833, where they were just raining out of the sky faster than anybody could count. So that really got astronomers thinking.

36:08
All right, what the heck is going on with these meteor showers? Is there any pattern to them? So one theory was they're like the weather you can't say why a meteor shower happens, any more than you can say why a thunderstorm happened today and in 1820, there was no way to know. The other theory was the cosmic theory, that they're caused by particles from space. So along comes our friend Giovanni Schiaparelli, one of the finest observers in Europe and an influential Somebody has Siri turned on Not anymore.

36:47
She's being as helpful, as usual.

36:49
Not anymore. So anyway, schiaparelli has the idea okay, let's do a rigorous analysis of this. And he exchanges several papers with his colleague. So anyway, schiaparelli has the idea okay, let's do a rigorous analysis of this. And he exchanges several papers with his colleague. Schiaparelli has an observatory in Milan, in a district called Brera, and has one of the finest telescopes in the world and looks at Mars with that. He's communicating with his colleague, father Angelo Secchi, s-e-c-c-h-i, who's down in Rome at the Rome University Observatory, and they decide let's analyze what's really going on here.

37:20
One thing you could do is figure out how fast these particles are actually going. Assume that the Earth is going around the sun. If you measure the speed of these meteors, schiaparelli found the speed of most meteors is about 140% of the speed of the Earth in its orbit. This is a magic number because in Newtonian gravitational physics that's close to the square root of two, and in Newtonian gravitational physics the square root of two times circular velocity is escape velocity. So the meteors were traveling at a speed comparable to that of comets in big, long elliptical orbits or parabolic orbits. So that was the first clue that there was a connection with comets was the speed. All the meteors had a similar speed when they entered the Earth's atmosphere.

38:12
And then Schiaparelli, in this book of his, goes through very carefully with an argument from geometry about the radiant, which is what you asked about like 10 minutes ago the fact that the meteors appear to radiate from one point in the sky. Well, the analogy that's often used is if you're looking along a railroad track, the parallel rails appear to converge to a point in the distance. So the fact that the meteors seem to emerge from a particular point in the sky, in this case from the constellation Perseus, that's a clue that they're traveling in parallel paths. And it also tells you something about the direction of the original cloud of particles, the original cloud of particles. So he uses geometry to reason how the direction of the radiant would tell you about A, the motion of the Earth in its orbit, and B, the motion of the stream of comet particles. You could work this out with geometry.

39:12
And then another cool thing that came along his friend Secchi, who's mostly known for using a spectroscope to look at stars, meteors, was not even a major thing with him. He said you know, if you have two observers like 50 kilometers apart and they could agree that they're watching the same meteor, they could note how high in the sky that meteor appears to them. Put their data together and use trigonometry, simple math, to figure out how high above the ground these streaks of light are. That's a fun fact. But here's where Secchi was the genius. He says and if you do a bunch of them and it turns out, there's a maximum height that could tell you how high the top of the Earth's atmosphere is. This is why I say these guys I think of. There's a temptation to think of these 19th century astronomers as a bunch of nasty old guys with beards, but these guys are really smart. Um, and for secchi, this is like an id he shakes out of his sleeve. You know, you could find the top of the atmosphere by observing meteors. Um, so they put it all together.

40:14
Scaparelli carefully reasons and identifies that the, the, the, the particles that make the perseid shower, share the same orbit as a comet that was discovered in 1862 that's now called 109p swift tuttle.

40:30
And then scaparelli says okay, what could the connection between comets and meteors be? He looks back through the records. In 1618 there were detailed observations of a comet actually breaking into little pieces. Nobody knew what comets were made of. But this was the first observation that a comet could actually break into pieces. And scaparelli says maybe that's what's happening is comets go around the sun sometimes. Sometimes pieces break off. They're in these orbits that reach this particular speed when they are near the Earth's orbit and, using calculus and Newton's laws, if a bunch of particles break off after a few orbits, they're going to spread out into a stream that goes all the way around the orbit and has a certain speed and a certain direction that can be explained by the appearance of the radiant and the sky. And so from naked eye observations, not bad-ass high tech, he puts together this profound insight into where the earth is, how it's moving, how the solar system is put together. So I think it's a great story.

41:31 - Rod Pyle (Host)
That is a great story. Uh, we're going to do one more quick break to pay the bakery and we'll be right back, so stand by. We're back, so hold on to your seats. John who Jammer B, also known as who's on the board today, has an image for us. So for those of you watching this instead of listening to us, we have a picture of a Perseid meteor from the International Space Station that was on the astronomy picture of the day site, which is pretty cool. It's just a little streak. We see one of the solar panels I think that's a solar panel, not a radiant panel Up on the upper right, the curvature of the Earth. We're past the Terminator, so it's dark and there's this cool little streak in the atmosphere. You know this reminds me a little bit.

42:12
I was very excited one year. You know this reminds me a little bit. I was very excited one year. Somebody was going to take us up in a private plane and I thought it's the 4th of July. I'll be able to see the fireworks from the sky. That'll be so cool and they look like little sea anemones opening up little tiny things. It wasn't very impressive, but this is rather cool because it's something that you wouldn't expect them to necessarily catch. I like it um steve you before we started that you had some stories about meteor, lore, like in various cultures, and so forth well there was.

42:46 - Steve Fentress (Guest)
So I said that those astronomers back in the 18 or late 1700s, early 1800s were first. That was when the first dawned on them that possibly meteor showers recur at predictable times of year. But it turns out there had been a tradition in particularly German Catholic regions that every August 10th the sky brings us the tears of St Lawrence. St Lawrence was an early founder of the christian church and he was uh, martyred in the year 258.

43:21
And the particular way it was done he was put on a gridiron and cooked over a fire nice pictures anyone the story about that is, while the flames were licking over him, he said I'm done on this side you can turn me over and for for that, saint lawrence is now known as the patron saint of comedians for being able to make a wisecrack like that during such a bad moment. Anyway, the tradition was that these things coming out of the sky were either sparks from the fire or his fiery tears, and so there had been a folk understanding of this for centuries.

43:59 - Isaac Arthur (Co-host)
Astronomers just didn't know about that's really amazing, I think, one of the things people get confused about. I do myself sometimes, just like with stalactites and stalagmites. Just tell the audience what is the difference between a meteor or a meteorite, a meteoroid?

44:13 - Steve Fentress (Guest)
yeah, the story is that if you have a little particle in space that hasn't hit the Earth yet, it's a meteoroid, and when it enters the Earth's atmosphere it makes a flash of light by heating the air that it goes through. It's not hot meteor dust, it's the ionized air, and so that flash of light is the meteor, and if a solid piece makes it to the ground, then that solid piece is a meteorite, but people you know reflecting over the year, I think during the eclipse, we gave people, at least in the planetarium business, so many do's and don'ts and rules. I'm not going to worry too much about those three words, but that's the technical difference.

44:58 - Isaac Arthur (Co-host)
And you said it's not a fireball, it's ionized gas. Do we get fireballs much with bigger ones?

45:03 - Steve Fentress (Guest)
Yes, if you have a bigger piece fireball, let's see the meteor society uses the term bolide, which is a fancy word for fireball, and that they apply that to any meteor that's brighter than any planet, like brighter than venus, and so that would be from a bigger piece of of stuff. Um, and any of these regular annual meteor showers made of comet particles can occasionally have a fireball.

45:28 - Rod Pyle (Host)
you just never know when I remember once years ago I was actually driving south during one of these showers I think it was the Geminids. I was driving down from Northern California on the 5 in a relatively dark area, I saw this massive fireball streak almost from horizon to horizon. It was amazing Bright green, and that got me curious as to what these various colors meant. So you can see a variety of colors. A fairly small set of them can see a variety of colors, a fairly small set of them. A variety of colors if it's a big enough display. What do those mean?

46:03 - Steve Fentress (Guest)
well, there are known colors from different atoms, like orange for sodium and yellow for iron I'm looking my notes here blue for magnesium, violet for calcium, red and yellow from nitrogen and oxygen in the atmosphere. So you've got different chemical elements in the incoming particle and in the atmosphere itself and the colors. I mean if it's really bright and the color is obvious, okay. If it's not so bright, the color can be pretty subtle and hard to judge. And remember that when you have something that's glowing incandescent, the color is telling you which chemical element is glowing the brightest, but not necessarily which one is most abundant. So, like if you see a blue meteor, that doesn't necessarily mean that this particle is made of magnesium. It just means that the magnesium atoms happen to be glowing the brightest. There there's a lot of different kinds of atoms, some of them in very small percentages, but if they happen to glow the brightest, that's the color you'll see.

47:02 - Isaac Arthur (Co-host)
I remember we had the Aurora Borealis just maybe a couple months ago and going out and looking. I couldn't tell if it was actually that or from the park up the road, but we took photographs of the camera because there's a lot of light pollution from that direction. We took photographs of the camera because there's a lot of light pollution from that direction. We took photographs of the camera. It showed up so much better on the colors. You could really see the reds and the greens. And I was wondering, because we have the Aurora, you do get a lot of problems with the radio at that point in time. Do you have any problems like radio communications, cell phones doing an intense meteor shower?

47:31 - Steve Fentress (Guest)
Problems Not that I'm aware of Problems, not that I'm aware of. Observing meteors by radio used to be a thing, especially when television was analog, because the hot ionized air ionized means that the atoms have had electrons ripped off, so you basically have an electrically charged gas, at least until the electrons and the atoms get back together, and so you have a cloud of this ionized gas and that reflects radio waves like a mirror, particularly at certain frequencies, like the frequencies that used to be used for analog television. So people would set up receivers and I guess you can still try it for AM radio stations. You want to set your radio to the frequency of a station that's like 900 miles away but you can't hear it. And if a meteor goes over in the right place, it creates a temporary mirror up in the sky that will reflect that station's signal to you for a few seconds and then it fades away.

48:29
With the switch to digital it's harder to do than it used to be, than it used to be, professor David Meisel who lives a few miles from me here and is a professor emeritus at SUNY Geneseo, was sort of a leader in organizing radio observations of meteors back in the 50s and 60s and 70s, but it's kind of faded. Some amateurs are doing it with more sophisticated digital equipment today and looking for digital signals, but it's not as easy as it used to be.

49:02 - Rod Pyle (Host)
So a little bit of a steer to the right here. For years, you know, we both worked in planetariums. You, of course, much longer than I, but I had a few years as a helper, not as a presenter. But it was pretty clear back in the eighties and nineties that these star theaters were beginning to go the way of the classical symphony orchestra, ie. It was getting harder and harder to sell them as a show, as a presentation venue, and of course different planetariums have tried different things. At Griffith we ran Lasarium for years which looked like a lit up spirograph on the dome. I thought it was kind of silly, but it was quite popular. But planetarium directors and show producers have tried a variety of things. What do you see as the future and what might be the way that this can hang on for something besides just young school kids?

49:58 - Steve Fentress (Guest)
Planetariums depend really, I mean, like many astronomical facilities, how well a planetarium does or what it does depends a lot on who the individual person is, who is running it, and so if the individual person is just, you know, renting canned shows from somebody like you know, like a movie or a laser show, and just running that over and over again, it's going to be a little dull. But the good news is there's a new generation of planetarium directors coming in and they're 30s and 40s. We've got now digital projection, so planetariums now have software. They can communicate easily with each other. Like, if planetarium A comes up with a good three-dimensional model of the Crab Nebula, they can share it with planetariums B, c and D, and there's some really smart people coming along.

50:51
You can never do it on admission tickets alone, although I will say my planetarium, the Strassenberg, was doing very well on box office revenue when I left and I understand it's doing even better on box office revenue since. And that's from opening up and being big enough. Yes, you can absorb running a Taylor Swift or a Pink Floyd or a Weekend or a Beyonce laser show or something like that. But developing the institution as a trusted and easily accessible community resource is what the new generation is into, and in the best places it's looking really good because they're smart, they're tech savvy. Communication with professional astronomers is better than ever. You know, we've got the internet. You can download anything you need quickly. So if you're talking about it, reminds me like movie theaters. It's been a long time since movie theaters made any money by selling tickets to public exhibitions in the United States. So you're not gonna do it on ticket sales alone.

51:57
But the key to survival for a planetarium is local renown and respect. You need not only the tickets, but donors and sponsors, and if you are a valuable community resource, you can get that, and a lot of places are doing that. So another thing that helps is to spend money on improving the place. That certainly worked for us when we did our big renovation for the 50th anniversary. Attendance went up some, but revenue went up a lot because people were willing to pay for a better experience, and some extravagance is rewarding. It doesn't always have to make economic sense. People will support something that is really well-liked and well-respected, so I'm optimistic actually.

52:46 - Isaac Arthur (Co-host)
So you mentioned extravagance in shows like that and I was thinking of so much science fiction, where you've got these beautiful displays that are sometimes always most scientifically realistic, but they help to, you know, let people really get entranced the topic, and on my own show we spend as much time in sci-fi as we do in science and and so I was wondering do you have any any good suggested reading for folks where they missed the showers? I want to you know any good stories, any good films or movies that spend time on meteor showers and nighttime viewing?

53:15 - Steve Fentress (Guest)
Films or movies that spend time on meteor showers or nighttime viewing. I have to think about that. There are the biographies of astronomers that you can look at Edward, emerson, barnard, milton, humason, people who were not trained as professional astronomers. There's a book called Starlight Nights by Leslie Peltier, who was an amateur astronomer back in the 50s and 60s, who became a very well-respected observer of comets and double stars, and he writes in this with pencil drawings illustrating his childhood Very beautiful tone about going out under the dark sky when he was a child on a farm in Ohio. I don't know of any movies that do a great job with meteor showers that I've seen, I will tell you. I'm going to steer a little bit off topic and tell you another popular culture connection, though Remember mentioned.

54:17
Uh, giovanni scaparelli figured out the connection between comets and meteors. His niece, elsa scaparelli, was a noted fashion designer in the art deco era in the 30s and 40s. There's a profile of her in the new yorker magazine, so she was just known as Schiaparelli, as gowns by Schiaparelli, and she was the costume designer for a number of movies, including movies featuring Mae West and Zsa Zsa Gabor. So not directly connected to meteors, but if you want to look at the 1952 Moulin Rouge with Zsa Zsa Gabor. You're seeing gowns designed by Giovanni Schiaparelli's niece. How about that?

54:59 - Rod Pyle (Host)
Did they have canali?

55:03 - Steve Fentress (Guest)
Among other things, talk about extravagance. She knew how to be extravagant, especially for a movie, anyway.

55:12 - Rod Pyle (Host)
Yeah. So I just wanted to ask one more thing for me. We've talked before about the Leonids, which can put on a remarkable display every now and again I think it's every 33 years, which I was fortunate enough to see when I was a kid in 1966. And as a kid it was terrifying, but it was also spectacular because the sky just lit up. When's the next time that might be expected?

55:35 - Steve Fentress (Guest)
We had a pretty good one in. Was it 99 or 2000? I remember seeing intense meteors and a great aurora display on the same night. That was incredible. So it would be due again about 2034, something like that.

55:51
I guess we have to stay alive that long yeah yeah, yeah, so the Leonids can be one of the heavier showers of the year, but I'm looking at American Meteor Society saying in 2024, don't expect more than 15 meteors per hour this time. But that's yeah, that's so the Leonids it's not going to be, I don't think, a big event for a while.

56:18 - Rod Pyle (Host)
Isaac, you got any other questions.

56:21 - Isaac Arthur (Co-host)
Let's see. We want to learn more about Scaparelli's work. You can always read up on John Carter on Mars for more of the canals. But if they want to learn more about meteors and sky observations, your book Sky and Space is still available, right.

56:34 - Steve Fentress (Guest)
Yes, sky to Space is still available, and it's really about I concentrate, I don't think I have meteors in there. It's more about things like why does the moon appear the size that it does? How long does it take for the sun to set? How can you predict what you would see if you were standing on one exoplanet looking at another exoplanet in the same system? It's basically how you visualize things, A lot of it done by drawing what I call the skinny triangle, where the point of the triangle is your eye and then the two sides of the triangle span whatever object you're looking at. If you can figure out how big that angle is, you can figure out all kinds of things about what you would be seeing.

57:21 - Rod Pyle (Host)
All right. Well, this has been been great fun. I can't wait to have you back and I want to thank everybody for joining us along with you guys for episode 123, 123 of this week in space. We won't have that numeric lineup for a while. The mighty perseids. Please be sure to check out isaac's youtube channel science and futurism with isa Arthur I hope I said that right For some of the most fascinating and brain stimulating material you're likely to see anywhere, and you can, of course, find the National Space Society, of which Isaac is the president and I'm well, I do a lot of things at NSSorg, and Steve remind us one more time. Can we get synopsis of your book and tell us about the forgotten bookshelf?

57:58 - Steve Fentress (Guest)
right, so the book is available on amazon. It's one of those print on demand things, so if you meet me somewhere I'd be happy to sign it. Um, but, totally unrelated to sky, to space, my new since leaving the planetarium project is my podcast the forgotten bookshelf readings. So interesting, they put you to sleep, set your sleep timer for 30 minutes. My podcast, the Forgotten Bookshelf Readings so Interesting, they Put you to Sleep. Set your Sleep Timer for 30 Minutes.

58:20
So in this podcast I read from things mostly fairly old, on topics that are fascinating. They just lead you farther and farther into irrelevance, like a book from the 1940s on how to load cargo on a cargo ship, a book from 1910 on how to operate a movie theater. Let's see, coming up in the new season I'll have one on ice. If you don't have refrigeration, what's the best way to make a big block of ice outside? One on gravel? So this is a geologist about 1911 who argues why naturally occurring gravel is stronger than solid rock. Now this should be of interest to you guys with your Mars settlements and your moon settlements. So that's coming up on the podcast, the.

59:15 - Rod Pyle (Host)
Forgotten Bookshelf reading. So interesting that puts you to sleep. Set your sleep timer for 30 minutes and you can get it at the usual podcast places. I'll be sure to mention to my jpl pals when I see them that mars gravel is the thing. And of course you can find me at pilebookscom or at astromagazinecom. Do remember to drop us a line when you feel like it at twists at twittv, that's twis at twittv. We welcome your questions, comments, insults and especially jokes. I'm counting on you. You're falling down on the job.

59:39
New episodes of this podcast published every Friday on your favorite podcatcher. So be sure to subscribe, tell your friends, give us reviews. We'll take whatever you got. Don't forget you can also get all the great programming with video streams and ad-free on Club Twit for only $7 a month. So if you go to the Twit website and feel like joining, we'd appreciate it. If you want to give more than $7 a month, we really appreciate it, but that $7 a month is helping everybody stay on the air in what are very challenging times for podcasts. Finally, you can also follow the Twit Tech Podcast Network at Twit on Twitter and at Facebook and at twittv on Instagram. Gentlemen, thank you, it's been a pleasure as always, and I'll see everybody next week. Take care.