Ep. 692 – Mission Roll Call Part 1: Orbiting Earth

It’s time for another series. This time we’re going to look at the missions that are currently in place across the Solar System. Today we’ll start with the key missions here on Earth, studying the planet from above and looking out into the Universe.


(This is an automatically generated transcript)

Fraser Cain [00:01:19] Astronomy cast. Episode 692 Mission Roll Call. Part one Earth orbit. Welcome to Astronomy Cast, a weekly facts based journey through the cosmos. We help you understand not only what we know, but how we know what we know. I’m Fraser Cain, I’m the publisher of university. With me, as always, is Doctor Pamela Gay, a senior scientist for the Planetary Science Institute and the director of Cosmo Quest. Hey, Pam. How are you doing? 

Pamela Gay [00:01:41] I am doing well. We are recording this episode early because on the day we would normally record it, my gallbladder is being removed. And I have to say, I am not entirely okay about this. But I am glad to be here and I am glad for all the patrons out there that allow us to do this show. And I just want to remind everyone that if you join our Patreon Patreon.com slash astronomy cast, you get all of our episodes completely advertiser free through the Patreon feed. So, if you don’t like the ads. 

Fraser Cain [00:02:16] And the warm feeling in your heart that you are directly supporting the salaries of the people who maintain this show. 

Pamela Gay [00:02:23] Yes, yes. And and my eternal fun. 

Fraser Cain [00:02:28] And providing truly independent space and astronomy education. 

Pamela Gay [00:02:34] Yes. Yes, and I will mispronounce your name regularly. If you, endorse us at just the right level. 

Fraser Cain [00:02:43] All right, go to Patreon, a astronomy cast. It’s time for another series. This time, we’re going to look at the missions that are currently in place across the solar system. Today we’ll start with the key missions here on Earth. Studying the planet from above and looking out into the universe. All right. Let’s talk about the spacecraft that are looking us down and who is observing our planet. And this all in just in, like, warn people in advance. Like this is an overview. There are like it’s going to be hard for the earth type stuff for us to really sort of provide a comprehensive list. But here’s some of the stuff that we think is really kind of interesting right now. 

Pamela Gay [00:03:25] Yeah. So at the broadest level, there are weather satellites from all the different nations that are interested in maintaining their own weather information. There are communications satellites, governmental, private, everything in between. There are, so many spy satellites, some new spy satellites. And then there’s, like, the stuff that this show really gets behind. We have two space stations right now. There’s the International Space Station, which really started construction back in 1998 and carried on from, what had been the Soviet Union and then Russia’s Mir space station. It was used as the training ground, and then I as us was constructed as a platform that, is very much a peacekeeping platform. They’re finally starting to do a fair amount of science, but the main mission is to keep a whole bunch of nations working together that might not otherwise work together. And then China that wasn’t allowed under the ice was like, okay, we’re just going to build our own. So, they’re they’re off to the side, they launch theirs. And 2021 and this is Tiangong, and they’re working to keep it, occupied a great deal of the time. And. It’s fun to track how many space toilets are in space. It is often been pointed out that the ratio of humans to toilets is the best anywhere that humans exist. If you go to orbit. 

Fraser Cain [00:05:06] Right. That’s funny. So. So where do you want to start? I mean, I think, you know, we’re going to not talk about the spy satellites. We’re not going to talk about the communication systems, navigation systems, starlink’s any of that kind of stuff. Right. Like that is not interesting to us. Yeah. It’s not it’s not that it’s not important. It’s just that’s novel being nerd out and obsess about. So. So what are the kinds of missions or what are the specific missions that you’re really interested and want to sort of highlight when we talk about what’s here at Earth? 

Pamela Gay [00:05:39] So, so I have to admit, I discovered in prepping for this mission, for this. 

Fraser Cain [00:05:44] Mission, I. 

Pamela Gay [00:05:45] Love it. It feels like it. Yeah. In prepping for this episode, I discovered NASA and ESA have far more earth facing satellites than I had any idea about. 

Fraser Cain [00:05:58] Yeah, I was a little sort of nervous when you suggested this is a topic this week. I’m like, this will be the longest episode we’ve ever done. 

Pamela Gay [00:06:05] Yeah. 

Fraser Cain [00:06:05] Five hours long. Buckle up everybody. 

Pamela Gay [00:06:08] Yeah. So instead of going through them one by one, which would be an act of hate, I think a good place to start is looking at what are the technologies that we employ for science on a regular basis. And the Landsat satellite is really the old. It’s. It is the one you look. It’s the one you look to for inspiration of. This is the way it’s done. Right? So the the lambs hearts are really the, the gold standard for Earth’s observatories. They are out there looking at our planet in myriad different wavelengths that allow them to see difference in water uptake by plants, different in differences in kind of plants from place to place, differences in soil and soil quality. And they were sort of that thing that allowed us to start to realize, hey, different places because of what’s going on beneath the canopy. If you change what colors of light you look at. You start to realize this is actually different vegetation and different basically under the Kennedy, a different reality. So yeah, they’re cool pretty pictures. 

Fraser Cain [00:07:34] Right? Yeah. And and you know, the Landsat series. Out there in the late teens at this point. 18 I forget which is the latest Lance at anyway. But but it is just like they started launching in the 70s. And so there’s just this continuous every couple of years another Landsat launches. They put new technology onto this spacecraft and then fly it. And so each one, as it comes online, has the latest and greatest technology for Earth observation and yet fits into this ecosystem of existing satellites. 

Pamela Gay [00:08:12] And so so you just accidentally merged two different satellite series. You just merged the Goes series in the Landsat. So the Landsat is only on number nine. The Gos are in their late teens. 

Fraser Cain [00:08:26] Okay. Sorry. Yeah. All right. 

Pamela Gay [00:08:28] So so the the Goes missions are put out by NOAA. So so we have Landsat is that’s out there doing the imaging thing doing the imaging thing. And Landsat images are great for things like watching sprawl the result of droughts, the result of flooding where you can see change in our planet over time. And you can start to understand how you can watch the changes in vegetation and everything else just through different color images, the Goes missions which are in there, I think late whatever number goes with the letter R in the alphabet. Right. They’re out there doing imaging as well, but they’re more tuned towards studying our planet’s atmosphere there. I’d in collaboration with the National Oceanic and Atmospheric Association, whereas Landsat is in collaboration with the United States Geological Survey. And this difference in collaboration partners that NASA has for these two different missions, points that are needed to understand both the land and the atmosphere above it, because they work together at any given moment, we probably have one Landsat, possibly two. And we also typically have four different GEOs satellites that are looking down. And one of the things about the Geo satellites that causes me great amusement and occasional sadness is they will often start out as like geos, el geos, and. It’s it’s spelled goes G. 

Fraser Cain [00:10:21] And I was trying to pronounce it just goes but sure. 

Pamela Gay [00:10:23] Yeah yeah I realized I was saying it wrong because this pun doesn’t make sense if you say it wrong. So the goes missions A through R now had goes P for a while, and while it was still on the planet it was referred to as gos P. But once it got into its station keeping orbit, they switched it over to having a number to name. And that brought me sadness. 

Fraser Cain [00:10:51] Right. So and I love this idea that you’ve got these long running programs where the goal is always the same. We want to have images of the Earth as high resolution as as we can. We want we want to keep track of the weather in as high resolution as the current technology will allow, and so that you’re constantly making sure that you have those spacecraft available to do this job. And they’re just constantly taking pictures at high resolution. They’re freely available. You can use them for whatever you want. And and that NASA makes sure and NASA and NOAA make sure these things are constantly a presence on Earth. And so that sort of is, is like more of like a generic kind of concept. Yeah. And so, you know, when talk about sort of some specific missions now that are trying to solve specific problems or questions, and we’ll talk about that a second, but it is time for another break. 

Pamela Gay [00:11:47] This episode is sponsored by BetterHelp. This is Beth here for Pamela. She had her gallbladder needed the day she’d normally record this show, and going into it, she was up until all hours with a brain determined to be shouty about all sorts of things beyond her control. This kind of shouty brain shenanigans isn’t restricted to extreme circumstances. Sometimes just reading the news can lead to a visit with 2:00 in the morning. If you want to quiet the voices in your head and find real peace, it can really help to talk through your thoughts while getting therapy. If you’re thinking about starting therapy, give BetterHelp a try. It’s entirely online. The mobile friendly website will have you fill out a brief questionnaire, and then pair you with someone who will match your needs. And if they aren’t a perfect fit, you can easily change therapists at any time. Everything is online and BetterHelp is convenient, flexible, and can work with any schedule, even an astronomer schedule like mine. Get a break from your thoughts with BetterHelp. Visit betterhelp.com/astronomy today to get 10% off your first month. That’s BetterHelp. Help! Dot com slash astronomy. 

Fraser Cain [00:13:07] And we’re back. All right. So let’s let’s talk about some like more specific missions that are trying to solve some specific question about about Earth. 

Pamela Gay [00:13:17] So, so there are a series of missions out there that are specifically measuring the, height of ocean water. And this designation, to measure the height of ocean water is something that serves a couple of different purposes. So on one side, this is something that continues to blow my mind away because of the rotation of the Earth, the, height of the ocean on the eastern coast and the western coast of continents is not the same, which is part of why you have to have the locks in the Panama Canal. It’s it’s because the ocean literally is a different height on both sides. Wow. So getting to see things like this, we’ve also been able to discover that there are gravitational anomalies by looking at the surface height of the ocean. There’s an anomaly out in the Indian Ocean, where our planet just doesn’t tug the way it was expected. And and so there are a bunch of different missions that are out there happily looking at our Earth and doing things like measuring the surface level of the ocean. 

Fraser Cain [00:14:35] And there’s there’s one mission, I forget the name of this from the European Space Agency, where they are scanning the ocean heights with such such accuracy that they’re able to measure wave heights. And so now they’re finding rogue waves out in the middle of the ocean. When before these. These are just the stuff of legend, you know, some boat would disappear and people thought there’d be a rogue wave. People say, oh, we experienced this enormous crazy wave. Yeah. Now it’s just tracking them all and seeing all of these rogue waves and noting their heights. And and it’s setting new records for how big waves can get out in the middle of the ocean in places that nobody’s ever experienced them before. 

Pamela Gay [00:15:12] And I love how just in the time that we’ve been doing this show, Rogue Waves have gone from being, I don’t know if you can call something a cryptid weather phenomena, but I don’t know how else to put it. The kind of thing that, like you told small children, those don’t actually exist. 

Fraser Cain [00:15:31] Rogue nation mermaids. Sure. Yeah, sure. You saw that? Yeah. 

Pamela Gay [00:15:34] Yeah. So so we’re we’re still pretty sure that that the mermaids don’t actually exist, but rogue waves? Totally. They’re totally there. 

Fraser Cain [00:15:44] Yeah. And then other, you know, you can measure the height. Then this other spacecraft, they’re looking at the height of ice and snow. 

Pamela Gay [00:15:53] Yes. So we have a series of different Arctic observers from, both European missions and US missions that are doing two different things or measuring the heights of the ice. They’re measuring the cover of the ice in the Arctic and around Antarctica, and they are measuring the reflectivity of the water and the ice that is there. And this combination of data, which requires a slightly different orbit because you’re trying to observe the poles. This is allowing us to catch things like, oh, shoot, a giant iceberg the size of name. Whichever state or countries currently the size of the latest iceberg has just broken off, and then track them as they both go across the ocean and melt, or go across the ocean and hit land forms and scrape them bare. And both are traumatizing in different ways. When the icebergs melt, they raise sea levels and change the salinity of the ocean when the icebergs hit land and scrape across it. The penguins that lake near places, and the seabirds that need places to reproduce lose their places to reproduce. So icebergs are finding all sorts of multiple ways to make life hard for seabirds and penguins. 

Fraser Cain [00:17:22] Right? Yeah. Thanks. Icebergs. Yeah. And. Yeah. Giant ocean lining ships in the early 1900s. There are Earth observation satellites that are analyzing the constituents of the atmosphere and the temperatures. 

Pamela Gay [00:17:42] And and here we have missions. And what’s cool is we also have trace doing the same thing at Mars. And I love it when we have the same tech at multiple worlds. Yeah. We we have different missions that are going through, and they’re either grabbing samples from the upper atmosphere, or they’re using a variety of different spectrometers at different wavelengths to measure the hazes in our own atmosphere, the clouds in our own atmosphere. Are, measuring things like the thankfully disappearing hole in the ozone layer. And and so this is giving that holistic. What is the Earth’s atmosphere doing that we need to both understand the, increase in things like skin cancer that we see as well as to more correctly model, well, things like climate change and global warming and acid rain and and yeah, spacecraft often tell us things about our planet we wish we didn’t know. It’s the ones around other planets that bring us joy and happiness. 

Fraser Cain [00:18:46] The resolution on these atmospheric sensors have gotten so good now that they can measure specific sources of methane. So yes, if you remember, there was that methane leak in the pipeline from Russia during the, you know, during the early war that, you know, someone had sabotaged the pipeline. And so it was bubbling natural gas up to the top of the ocean, and you could see this giant methane blob that was hovering over the ocean. And they’re able to track methane emissions, leaks from pipes to see factories that are expected to be cleaning up their methane, that are actually releasing it into the atmosphere. And you’re getting to the point now where these spacecraft can just spot any individual methane emission that’s going on and then figure out, you know, people can figure out whether that’s supposed to be there. But should it be, you know, is there a lot going on? Yeah. And we’re right around the corner from the same thing with carbon dioxide. 

Pamela Gay [00:19:42] And so forth. 

Fraser Cain [00:19:43] Yeah, yeah. And so some of the largest power plants around there, specific carbon dioxide emissions are now visible from space. And so we’re getting to a point where you can actually track back carbon dioxide emissions to individual facilities that maybe, you know, should be using scrubbers or capture technology and aren’t. And so hopefully this will be a really powerful tool to be able to keep track of, of atmospheric emissions as we move forward. 

Pamela Gay [00:20:12] Filed under the category of more things are satellites have allowed us to know that we wish we didn’t, early during Covid, it was actually Earth observing satellites capable of measuring the constituents in the atmosphere that were able to allow people outside of China to understand just how bad, Covid was affecting, China because of atmospheric changes, due to increased use of crematoriums. And, and so we are at the point where we can literally see the output of crematoriums and its effects on the atmosphere and assess death rates from that. So things you didn’t want to know and now you do. Can we switch to something happier? Can I bring you something happier? 

Fraser Cain [00:20:59] All right. I’m. I’m fine with happy. What do you. 

Pamela Gay [00:21:02] Hey. Okay, so my favorite thing that Earth satellites are used for is lidar. Because with the correct lasers, you can, basically look through the forests and find Mayan ruins. You can I get two slightly different, reflectivity of different land over archeological sites, and we don’t think about it, but we are on the regular. If we are outside at the right moment, we are getting hit with laser light from these lidar systems that have, like, half meter resolution to meter resolution on our planet, and they fire down massive amounts of green laser or other color laser, they’ll only detect a handful of photons going back up. But these results are allowing us to see ancient civilization sites without having to actually dig them up. And so we’re starting to see what were the roadways associated with different known cities, what were these smaller townships and ancient societies with? With Mayan ruins? There was a case of a kid finding, using different maps and different information from, Mayan sources being like, there should be a city here using Google Maps going, yeah, this actually looks like there could be a city here. And then folks with lidar being like, yeah, we actually think we can see where the roads are. And and so there are a lot of places, specifically Mayan, Incan, Aztec ruins that got consumed by forests that make it nearly impossible to go in with a, archeological scouting unit. That can’t say for certain whether or not they’re going to find something. There’s just not the budget to support that kind of thing. But with lidar and multi wavelength observations, we are actually able to peel away the surface of the world and say, this is why we see turquoise from the American Southwest so far into South America. This is why we see bones from things that were only in South America, as far north as the Cahokia mounds on the Mississippi. We’re starting to uncover the vast civilizations that built stuff with dirt, or built stuff that got eaten by forests that otherwise we’d never be able to see. 

Fraser Cain [00:23:55] Sort of. On a side note, we had a lighter scan done of our property when we moved here, and it’s down to centimeters resolution. 

Pamela Gay [00:24:04] From an airplane? 

Fraser Cain [00:24:05] No, from a drone. So they fly a drone over the property with lidar equipped to it, and then they just scan the whole property. And so I have a file that is about 200GB. That is my entire property scanned down to the centimeter ish resolution. And so it’s like individual trees, right? Like, oh, I see, you know, there’s that tree and there’s that tree. Yeah. And it’s and then here’s this open spot and here’s the rock on the ground over there. And, and it’s quite astonishing what can be done with these, these lidar. Now you’re not going to get the same resolution because you’re flying at a much higher altitude. But I love how, you know, when we think of Earth as a planet, as an astronomical object, it is worthy of study. This is what it feels like to properly have a world under study that, you know, you think back to like Star Trek, and they want to send in a probe to to analyze a planet and search for bio signs and, and, you know, study the atmosphere and so on. Like, we’ve got this on Earth. We have multiple spacecraft that are producing maps of the surface. We’re studying the atmosphere. We are studying the the water, the height of the water to submillimeter accuracy. We are detecting the amount of forest cover, forest fires, air pollution, migrations of lifeforms, hidden cities, all of these things thanks to space and satellites. And we couldn’t do this. Like, we just wouldn’t know as much about our world without being able to fly in space. 

Pamela Gay [00:25:48] We did do what I suggested with Jupiter, and we stuck one of the Earth observers at the Lagrange point. Looking back. NASA’s discover mission is out there, getting constant views of whatever’s facing the sun and just watching the world rotate. 

Fraser Cain [00:26:03] This is my response to the conspiracy theorists who were always like, how come there’s no pictures of Earth? I’m like, go check out the discover feed and they take pictures, you know, whatever. A dozen images a day of the Earth from the L2 Lagrange point. It’s the entire planet. 

Pamela Gay [00:26:18] It’s amazing. 

Fraser Cain [00:26:19] It’s amazing. And you can watch and see the storms that you’re all familiar. Only there’s hurricane Lee forming in the Atlantic. There’s this storm that’s currently battered. Here’s the cloud cover that I am currently experiencing. And you can see it’s I mean, you can see this in the goes images as well, but it’s it’s more zoomed in. But but the one that shows just the whole planet is the discover feed. And you know, you can just keep updating these images and see the planet changing hour by hour all the time. Yeah. So like this is it. This is the image. Like if you reject this image, then you just literally reject evidence entirely. 

Pamela Gay [00:26:55] Yeah. 

Fraser Cain [00:26:55] And so there’s no point having a conversation. So anyway now I have you know we are out of time and yet we’ve only talked about looking inward. We haven’t talked about looking outward. So I propose that we split this episode into two pieces. And next week we talk about the the satellites that are orbiting Earth that are not looking down, that are actually looking out. 

Pamela Gay [00:27:16] Sounds great. I will update the calendar. All right. Life is good. 

Fraser Cain [00:27:20] Yeah. And I, I reserve the right to extend it again because there’s a lot of cool stuff that’s out there. So this could this episode could be the remainder of our careers, this series or, you know, we might stick to the schedule. We’ll see what happens. All right. Thanks, memo. 

Pamela Gay [00:27:37] Thank you, Fraser, and thank you to everyone out there. As a reminder, if you, contribute to our show at the correct level on patreon.com slash astronomy cast, I will attempt and likely fail to pronounce your name once a month. This week I would like to thank Semansky shine, Sam Brooks and his mom, Andrew Stevenson, Stephen Coffee, Benjamin Carrier, Cami Racine, Frank tippin, Bart Flaherty, Nate that while. The lonely sound person. Dean Philip Walker of the air. Major John Drake. Bryan. Kelby. Lu. Zeeland. Nilu. Jesus. Trina. Plant star. Sidney. Walker, Jordan. Turner, Robert. Hummel, Paul. Esposito, Bob. Czapski, Arthur. Lat Hall, David. Borger, de. Boer, de I don’t know. I’m sorry. Sabra. Lark, Hal McKinney, Bruno. Letts, Jimmy. Bergen, Reuben McCarthy, Daniel. Donaldson, Ron. Thorson, Jason. Kidd, Dorcas. Time Lord, I row, Frank. Stewart, Christian. Golding, Wil. Hamilton, Sterling. Gray, Adam W, Simeon Thompson, just MacDonald and Lee Harborne. Thank you so much. 

Fraser Cain [00:28:55] Thanks everyone. And Pamela here is to a quick recovery. 

Pamela Gay [00:28:59] Thank you. 

Fraser Cain [00:29:00] We’ll see you next week. 

Pamela Gay [00:29:01] But by. Astronomy cast is a joint product of the universe today and the Planetary Science Institute. Astronomy cast is released under a Creative Commons Attribution license. So love it, share it, and remix it. But please credit it to our hosts, Fraser Cain and Doctor Pamela Gay. You can get more information on today’s show topic on our website. Astronomy. Cars.com. This episode was brought to you thanks to our generous patrons on Patreon. If you want to help keep the show going, please consider joining our community at Patreon.com Slash Astronomy Cast. Not only do you help us pay our producers a fair wage, you will also get special access to content right in your inbox and invites to online events. We are so grateful to all of you who have joined our Patreon community already. Anyways, keep looking up. This has been Astronomy Cast. 

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