Super-Earths _ Evaporating Planets with Anjali Tripathi

Coming up on StarTalk, we've got a Cosmic Queries edition all about exoplanets. I've got with me one of the world's experts on that subject, Anjali Tripathi. Welcome to StarTalk. We're going to find out where she came from, where she's been, and where she's going in this world of not only exoplanets, but also as a citizen scientist serving two presidents. Coming up on StarTalk. This is StarTalk. Neil deGrasse Tyson here, your personal astrophysicist. Today is another Cosmic Queries ever-popular format, if that is, on the subject of exoplanets.

Chuck.

Yeah.

My co-host. How are you feeling, Chuck? I'm feeling great, man. Feeling good about the exoplanets? Exoplanets are always fodder for great thought, because now we know that there are millions and millions of them born. They're everywhere.

I don't know if the catalog has quite hit that yet.

We went from four. They were like, maybe there's four.

So I don't know a little bit about exoplanets, but if we're going to really go in with the cosmic queries, we bring in the big guns.

Yeah.

Okay. So we combed the landscape and we found Anjali Tripathi. Anjali. Welcome to StarTalk.

Thank you so much. So excited to be here.

Excellent. Excellent.

You, in your professional life, not only did original work on exoplanets, you also found yourself, either on purpose or otherwise, at the intersection between science and society.

Absolutely.

So I want to get to that in just a minute. Right now, you're a research associate at NASA's JPL.

Lovely.

Which, Chuck, stands for what?

I believe Judy Paulson Lingerie.

That's right.

Judy Paulson's Lingerie. It's all the rage.

That's usually classified. Why'd you let that one out?

That was classified information. Yeah.

Now the awesome Jet Propulsion Labs. The Jet Propulsion Labs in Pasadena, California.

California. Yes.

And it's not only a branch of NASA. They collaborate internationally. and are basically on the campus of Caltech, right?

I am a Caltech employee.

Right, right.

So who signs your checks? Is it Caltech?

It is Caltech.

Wow.

Okay, there it is. But you still have NASA overlords.

I do.

I'm pretty sure you do.

You know who we had on StarTalk just when she just started was the director of JPL, Lori Leshin. She and I served on a commission to study the future of NASA.

Wow.

We were both appointed by President George W.

Bush.

Nice.

And she went on to great things.

And you got.

Stuck with me. I'm so sorry. I'm so sorry.

What a shame.

But you can dig the Lori Leshin episode out of our archives.

That was fun. Right.

I wanted to get to her before NASA got to her. Because, you know, NASA, they want to over-control the interviews. But she and I go way back.

Right.

So there was an interval where let's just rock and roll this.

Exactly.

Just say what you think. Think what you feel.

Yeah. Well, you're not going to be able to do that with Anjali because NASA is still controlling her. Sorry.

I have the NASA handcuffs on.

We'll figure something out here. So at JPL, what are your primary concerns?

I like thinking about what can we see from space, right? So what can you see when you look up at exoplanets and other worlds and also looking down here on Earth and how we can improve life.

Here on it?

You know, people, when they think of space exploration, they don't always think that from space you can see Earth as a planet.

Exactly.

And monitor what's going on and how we doing, you know. So this seems to be a really important feature of what NASA can deliver to the public.

Yeah.

It's something folks always get wrong. You ask them, what's our most studied planet at NASA?

And they go, Mars. And you go, wrong.

And you think, it's Earth. And nobody realizes that.

Exactly.

So you still have roots back where you got your PhD?

I do, yeah.

I'm a research associate at the Harvard-Smithsonian Center for Astrophysics.

OK. All right.

So tell me, before we get back into exoplanets, because that's where we got all the questions are based on those.

Yes, they are.

Just the science and society part of your life. How did that begin?

So being a valley girl, you know, we had an earthquake in the 90s and I had to move out of my house for a year. And the people who come on TV, for those of you who've had the pleasure of earthquakes, it's a seismologist who comes and tells you what's going to happen. And I thought scientists can come and tell you what's going to happen next and sort of save things.

I want to do that.

And then I learned that seismology and geophysics and physics are important, but they don't save the world in the same way. And so thinking about how you can find connections between science and servantry.

You know why they don't save the world? Because they only bring the geologists on.

After the earthquake. After the earthquake. Not just before the earthquake. After the earthquake. It's true. They're saving nobody. It's a doggone shame because when do we really need them? We just got some readings in. That's when we need them.

Whereas with the astronomers, we're like, that eclipse, get ready.

It's coming in six months.

Okay, so total predictive powers. Yeah.

All right, so now what? Okay, so the urge doesn't make the reality.

So what happened?

I mean, I was lucky enough. I went and served in two administrations. President Obama brought me in as a White House fellow.

She was lucky.

That was just luck. I was going to say. That was just luck.

I mean, I don't like to talk about the bribes.

I served in two administrations. That's funny. I used to serve at Wendy's. I was Wendy's manager, and I served for two tours of duty. Thank you for your service. So who was your first president?

Well, I mean, I was born a while ago. A lady doesn't reveal her age, but of the two administrations.

We're going to triangulate on that if you give us enough information.

President Obama.

President Obama. Oh, okay. Okay.

And so in what capacity were you serving in.

The White House?

So I came in serving the U.S. Department of Agriculture, thinking about climate change. You know, it doesn't matter why your soil is dry. You got to get things to grow.

That's right.

Is there a relationship between the Department of Agriculture and the Environmental Protection Agency?

I mean, so I was working on food waste, right, which is something that both care about, right?

Big deal.

Because, I mean, you know, your apple that you don't eat turns into methane.

Methane.

Greenhouse gas, right?

Yes, without a doubt. All right.

So, but you didn't just... So how does the Obama administration... connect you to agriculture? What is that pathway?

Uh, you know, where else would you put an astrophysicist in government?

What was your, what you, what was your title?

I was a White House fellow.

Oh, you didn't say that. Oh, okay.

A White House fellow. And so you have these science fellows at the White House.

So the White House fellows are actually, I was the only scientist, right?

Yeah.

So it's a group about 16 in my class, right? So one of them is now a Congresswoman. We've got all kinds of folks, a lot from the military and business and law. The idea is you go and you serve a cabinet secretary as a senior advisor.

Because the cabinet reports to the president.

Right.

So this is still a White House thing.

Exactly.

So the secretary of agriculture then became.

Exactly.

Right. Who reports to the president and you were working with them.

I'm intrigued by the fact that you get a PhD studying exoplanets. So you're thinking about planets looking at them from afar.

Right.

And then Earth and agriculture becomes Earth that you're thinking about from afar. So what kind of. NASA or astronomical insights can you offer the Department of Agriculture?

Well, I mean, I want it to be more down to earth, let's be honest, right?

And the idea is just that, you know, you can see so much more from satellites than you can.

With a guy walking around with a mule.

They offered to send me to estimator school where they said, you're going to walk a certain number of paces in a cornfield, pick the second ear of corn you see and count the diameter and across. And that's how we estimate the crop yields in America. We still, to this day, don't use satellites technology for the government predictions on crop yields.

Was this Green Acres? That's crazy. You got Arnold the Pig predicting the weather? Hey man, so how big is your corn? That's crazy. It's quantitative.

You count.

But I mean, it's one of those things that it's really useful for all the companies that come in because then it's calibrated ground truth.

Okay.

In a way, that makes sense. But isn't it much better to look because you can see from space you can actually see soil conditions you can see the the crop yields themselves there are I mean how dry it is how dry you can see you know there's so much more information you can get from looking down from above so it's what's going on with that?

I mean, and so to your question, right, there is tons of NASA data that looks at the soil moisture, it looks at sort of the different vegetation, and that's all publicly available both to the agriculture department and anybody else.

And to the person pacing cornfields. Right. Correct. It's available to them. Right. But maybe they need a job. Exactly. The farmer needs a job. I don't know.

So, no, so I'm intrigued by this. So, okay, so that was a tour of duty. It went across the administrations.

That's right.

But then you ended up, you told me offline, you ended up at the Office of Science and Technology Policy, which is the executive branch that oversees the budget for science in the United States.

Wow.

For science, yeah.

For science, right. And so what were you doing there? What are we doing with that $ 13.

26? What are you talking about? You said the budget for science. Oh, this helps me. It's a little bigger than that. I was going to say, that's what it seems. There's a lot of.

Science that they apply to the military. And so then you're talking big bucks. Okay, I'm just saying.

There you go.

Like Department of Energy. That's some nuclear stuff right there. Some nuclear stuff going down.

Right on. Okay. So go.

No, I mean, you know, writing about, hey, what are we investing in? What are the people and the programs? And I figured that we added the word American in front of everything we want to do. So we wanted American health, right?

Not just health.

American health.

That was smart.

Thank you.

I mean, that is brilliant. Because when you look at Congress. Merck. You should have made it that. Instead of American. You got to spell it right. Apostrophe M-U-R-I-C-H. Merck.

Merck.

They didn't teach me that one in my spelling classes.

So that was clever.

And so now more people across the aisle can take ownership of it.

Right.

That's right.

Yeah.

No, I mean, it was, I will say coming in to a new administration, it's kind of crazy. Your hard drives get wiped. Everything is gone. You're starting fresh a little bit and lots of opportunity to learn. So whether you wanted me to have that opportunity or not, but I think, you know, we did some good stuff.

But would you have normally been discarded between administrations?

No. Oh, how did you stay on?

So White House fellows have a one-year appointment that's fixed.

And so started August of 2016 and went to August of 2017.

Oh, you started at the end of the Obama administration.

I did.

Oh, so you crossover. You were a part of the transition.

I was, yeah. Wow.

Very cool.

So at the time, you told me, again, offline, that you knew I was on a Pentagon board at the time. How did you know about that?

Because I go into five-sided buildings. I can handle that, not just four-sided ones.

Okay, right on. How many five-sided buildings do you know? I don't know because I work at the Hexagon. Right. Okay, that's top secret.

Why do you think the telescopes have these hexagonal mirrors, right?

Yeah, yeah. The mirror segments of JDRC are hexagonal. That's right.

So that's top secret nobody knows about except for you. There you go, that's right. You know where we came up with that idea?

At the hexagon. Not the pentagon.

Okay, what's your most recent published paper? Was it about climate change?

Yeah, we just wrote a paper together about sea level rise and how you can use satellite data to actually do a better job of preparing coastal cities for sea level rise.

Excellent. Which is only where most everybody lives.

Every major city is on a body of water.

What can satellites do for you?

Okay, but again, it sounds like the seismologist, it's like, here's what to do when the water knocks at your door. Is there preventative advice in there?

No, so this is all about how cities can look at glaciers in Antarctica and Greenland melting now to prepare for what's happening in the future, right? Rather than waiting for the level to actually rise, that.

You have some early warning. Oh, so you can make predictions and anticipate. Got it. That's amazing. Got it.

And plus, I'm not thinking about Antarctica or Greenland when I don't live near them. But their water doesn't carry passports, right?

That's right.

Their water molecule will go wherever it goes.

Yes, exactly. So let's get back to exoplanets.

Absolutely.

So your work for your PhD was what?

Thinking about how planets form and how they evolve over time.

Oh, formation of exoplanets. Nice. So somebody had to make them. That's right. They're not just born whole. No, exactly. Okay.

So Chuck, you've got questions for us.

We have them right here. Let's do it. You want to jump right into this? Let's do it. All right. I love this first one. This is Monchelle Hicks. And Monchelle says, hi, Dr. Tyson. Hi, Anjali. Planets are evaporating? That's it. That's all that it says.

I mean, Montreal's got it down. Planets are evaporating.

Right. Right?

I mean, we've got the Earth. We've got exoplanets, right?

Because you've got all this gas that we call the atmosphere that's trying to stick to the planet by gravity. But sometimes you've got the heat from that star that's enough that it just pulls it off.

Well, we're losing, what, helium and what's the other thing? Hydrogen. Hydrogen and helium on a daily basis.

Hourly, minutes, seconds.

Yeah. Wow.

Okay, but not so fast that I should worry about it and make a thing on it.

But if.

There's stars that get brighter or more luminous and they're gash rich planets So they how about those big Jupiters that are orbiting close to their host or are they evaporating?

Yeah, these planets right that we call hot Jupiters because they're so close in right right and especially since they've always got one side and often facing the Stars the same side.

Exactly moon is tightly locked to us. Right you get close to a massive source of gravity It's going to lock you and only look at one side, just as we did to the moon. The moon is trying to do that to us.

Did you know that? Yeah, just lead us down the wrong path. A new path. A new path.

Yeah, don't value judge the path.

A new path. It's just the orbital mechanics of it. Come on, we're going over here.

Come on.

It's interesting. Let's go. So the moon is trying to slow us down so we only show the same things to it. Yeah, that's why we throw in leap seconds every now and then to make up for that. So wait a minute, with the evaporation, just because I'm concerned about Earth, to be honest, what's going to happen first? Well, our atmosphere, which I understand from Neil, is like thinner than the skin of an apple. Okay, it's thinner than the skin of an apple. Will that evaporate before the sun expands and kills us all? Or what's going to happen first?

All right, Chuck, don't worry about it. Don't worry about it. There's a lot of things that will scare you, but this isn't one of them, right?

So the idea is that you will have this atmospheric escape, is what they call it, because your atmosphere is literally escaping the planet, happening more and more.

In the future as the sun gets brighter, but it's not all going to go away before then.

So you're safe.

Okay, so.

You're good, but again, if you were.

We'll be crawling around the surface of the earth trying to breathe.

Right, stay low. Like you're in a fire. Stop, drop, and roll. Just so you can breathe.

Well, I think you're going to want to go up towards the poles or something like that. The equator's not going to look so hot. Or maybe it is going to look so hot.

Yeah, that's the problem.

Well, you already got this planned out. You need to join a Santa Claus.

All right, what else you got, Chuck? All right, here, this is TJ's show, who says, hi. TJ here from Winnipeg, Canada, eh? He does not have that in there. No, they don't. Okay. They do not. Okay. Okay. It says, thanks for taking my question. Hello, Dr. Tyson, Dr. Pathy, and Lord Nice, longtime listener and new Patreon here. My question is about intelligent life. If there are roughly 10 million unique organisms on Earth, 99% of all species that have ever existed are extinct, and we are the only intelligent species out of all that. Questionable. Let me say. Questionable. Big assumption.

Big assumption. Then doesn't that mean that the likelihood of there being intelligent life on a newly discovered habitable world is about one in a billion? Oh, I like that. Okay, so there you go. He's fast back at the envelope math thing. Back at the envelope math there. Yeah. So he says, yeah. And then he goes on, our galaxy might be teeming with light, but intelligent light could be extremely rare.

So let me recast that in another way. So his earth is this one branch of vertebrates coming out of fish that became great apes.

Right. Okay. Okay. I've known some apes, but not all of them were great. Well, no.

Some of them were just not so great. And one thin branch of that are the humans. Anything could have stopped that.

Right.

The asteroid not taking out the dinosaurs would have disrupted the mammals from ever even, quote, ascending to where we are.

To where we are. Just sheer luck. Exactly. Okay? Bad luck.

So if this is just one branch out of the tens of millions of life forms, if you have tens of millions of Earths, close your eyes and throw a dart.

Really? Most of them will just have life like we got here. Just life, but it will not be developed intelligibly.

I'm just saying I'm not smart enough to know what else is out there in the universe and certainly not the numbers of that.

So I think, you know, if we're being honest, do we know if there's life out there? I don't know. Do I hope there's life out there? Heck yeah. Do I hope it's intelligent? Heck yeah. But the numbers one in a billion.

Let's take the intelligence out.

Okay.

Now, the fact is. It's already out. Let's factor that out. What is the likelihood of just life? I don't care if it's single celled life. I don't care if it's just, you know, like, you know, some type of bacteria, amoebas, whatever. What is the likelihood of that happening? Seeing as how, you know, the same building blocks that we have here are everywhere. Plus, it happened pretty quickly. Yeah. Yeah. I mean, we're only four point five billion years old and we got to the life part pretty damn quickly.

I mean, there's planets everywhere, right? Like every star has planets.

And so if you think about we've got so many planets, so many balls of rock are probably amongst those planets. Chances are good you had the conditions for life, right?

Water, some energy. Those things seem like they're out there. So I think the chances are good. But again, one in a billion? I don't know if it's that slim.

Plus, we're not even limited to rocky planets anymore because there's some good moons.

There are some great moons. It's that habitable world, right? Not just the habitable planet.

It's habitable worlds, not just planets.

There you go.

World. Forget planet, non-planet. World. There you go. Yeah, yeah, yeah. I mean, even like an ice world would be like an ice world like Enceladus.

Yeah, you got that water underneath, right?

Yeah, but that can happen, right? Totally, yeah. All right, here we go. This is Dylan, and Dylan says, greetings, everyone, from Flagstaff, Arizona. I'm taking undergraduate astrophysics courses and learning about spectroscopy. Thank you. Spectroscopy. Spectroscopy. I can't do that. It always gets me. And other amazing methods of how to find and characterize planets, what has been the best method so far to find planets, and what possible new methods are being thought of?

So let me focus that down and have you tell us, we're now using spectroscopy to study the atmospheres of these planets. So what's coming out of that?

I mean, it's amazing that when you get just the right configuration, that you've got the star and the planet passes in front of it and you're looking at that, some of the light goes through that atmosphere of that planet from the star and gets to us. And so we can actually see some of those chemicals in that atmosphere.

That's amazing.

So the chemicals are.

Or disrupting, really, the clean path of light from the star. And that disruption shows up in the spectrum. Right.

They were like putting their fingers on there, getting those fingerprints.

So what are you looking for?

So we've seen carbon dioxide with the James Webb Space Telescope, which is pretty cool.

Right.

First time we've seen that on another exoplanet.

All right.

Right, all kinds of other compounds, right? You get water, right?

Okay, sure, water molecule, yeah.

Right, and you got some good things in there.

And so all kinds of configurations of oxygen and carbon and hydrogen that you think about.

Methane.

Methane is pretty great, right?

You get methane there too? Have you seen it yet?

There is methane about on the planets, yeah.

Okay, okay.

That would be evidence of?

Farts.

It can be, it can be.

All right, keep going, Chad. That is so cool. This is CESAR.

By the way, just to bring closure to that, To say the boring, obvious fact, so many of these planets were discovered.

Exactly.

Were discovered just by their spectra.

Right, and by transits, right?

That you looked at the light and you saw it blinking, and that's just because something kept going around at that light.

Of the star.

A transit is the planet going in front of the star's light, rocking the star's light.

It's just like when we have eclipses where you block out the whole face of the star, but here it's just a fraction of it, right?

So we talk about.

In fact, solar eclipses are really transits.

Yes.

Yeah.

We talk about the transits of Mercury and Venus?

Yeah, yeah, yeah.

Mercury transit, Venus transit. It's a moon transit.

That's right.

And an eclipse, technically, astronomically, is just object moving into the shadow of another object.

Okay.

So a total solar eclipse, really, we shouldn't use the term eclipse, but we do.

All right. Nice. This is Cesar Erno, who says, hello, Dr.

Tyson, Dr.

Tripathi. Is the James Webb Space Telescope used to look for exoplanets?

Heck yeah.

Okay. So why don't we just zoom in on some exoplanets and get high focus? She said, heck yes. Heck yeah.

Heck.

We heard that. No, let me hear it real. You're in New York City. You're in Manhattan. Say that right. F * * * yes!

I'm sorry. I don't know if I can beat that. I think you can.

Chuck wins that. I'm sorry. Chuck did that. That was just too New York. I couldn't help it. That's a long bleep on that one. Okay.

No, I think if I had the teacher, instead of I love New York, it would be I love GWST, right, for the exoplanets.

Oh, yeah, yeah.

James Webb Space Telescope.

So I thought it would only be looking closer at exoplanets we've already discovered. Is there a discovery mode?

There are discoveries, too, yeah.

How does it do that?

I mean, it actually captures pictures where you see that there's planets in the space.

Wow. Without knowing that in advance.

Yeah, yeah.

Oh. So he said, why don't we just zoom in and get some high-quality images? That's what it's doing. And that's exactly what you just said it's doing. Wait, wait.

So you see the host star and you see the planet.

You get a hint of the planet being there.

A hint of the planet.

You get a little dip of tea, right? Dip of planets.

Gotcha.

But the question of can we zoom in on planets there? James Webb is looking. different patches of sky. And if there are planets in there, that's great. But it can't look at just any part of the sky and say zooming in deeper and deeper because planets don't give off a lot of light. They're just reflecting their starlight, which is so faint that you don't see it most of the time.

Yeah. Got you.

All right.

This is Gavin Bamber, who says hello from North Vancouver, where plant life flourishes. And he's not blind. That's an orphan. It's so green up there. Oh, you can go green blind up there. It's crazy. It's crazy. He says, once we find plant or animal life on other planets, will we be able to eat it? Or can we tell if we're able to eat it? Or for Chuck, will we be able to smoke it?

Well, that's a question for you, Chuck.

Wait, did he say that? Yes, he did. No, he didn't. Yeah, I swear to God. For Chuck, will we be able to smoke it?

Okay, so let me ask this. So can we only... I don't know how much biology you know, but can we process... organic matter that has a different DNA from us. Like, our DNA is right-handed. Like, it spirals this way.

Yeah. Like, clockwise looking up. A double helix.

Yeah, but in principle, you can have DNA doing the other direction.

Right.

The chemistry shouldn't matter.

Right.

Right?

Except we don't. And all those people's skin is on the inside of their body. That's how all their organs are on the outside. They are so messy looking.

So, what is the scholarship on Just the digestibility of life forms that are not native to Earth.

A researcher doesn't eat and tell, Neil.

A researcher doesn't eat and tell.

I don't know why that got me.

But, I mean, I would say, you know, would you want to, though, right? Because, I mean, there's so many things that you're like, oh, that cheese doesn't look quite right. I don't know if I want to eat that. Now you're going, I just found.

This out there. I foraged for some while.

Yeah, yeah, yeah. That looks tasty.

There's a whole lot of stuff on Earth you know not to eat. Now, are you that desperate to eat aliens?

Right, I'm just saying, would you want to?

So this is Daniel L. Thompson, who says, howdy, Dr. Tyson, Dr. Tripathi, and Sir Nice. That's Lord Nice. He says... Lord is above Sir. Lord, exactly. Lord is totally above Sir. Why would you demote me? He goes, I'm Daniel from high school in the AFJR ROTC. Junior Air Force Reserve Officer Training Corps. Good for you, buddy. Nice. He says, has there been a minimum and maximum size or density to define what would be survivable for humans to live? I like that. I like that. Yeah. And P.S. Chuck, you're welcome for the easy name. Well, thank you, Daniel. But you can't take credit. I'm going to thank your parents for that. But anyway. Is there, I mean, I suppose planet sizes and other pressure, atmospheric pressure or gas planets, whatever.

All those things would have a.

There was a movie, The Space Between Us, where someone grew up on Mars. An astronaut got pregnant on the night before the launch.

Yeah. And it takes nine months to get to Mars. Right.

And NASA had to hide that information. So she gave birth on Mars and no one knew about it. And then the kid came back to Earth and it was like.

That's pretty cool. He had a hard time breathing. Yeah. And all the things he was used to on Mars, his muscles couldn't handle. But he was still alive. It didn't kill him.

So do you have any thoughts on survivability of low or high gravity?

I mean, I'm a big fan of Earth, right?

So like looking for planets like Earth because I like being able to jump up and down rather than Jupiter.

I don't know.

Jump up.

Where are you going next, right?

Right, right.

And having that nice solid surface. So something sort of the size of Earth is nice and cozy.

We seem to do okay.

Oh, I see. The point is, if it's much more massive than Earth, it's not a rocky planet. It's gaseous. You're getting gaseous. Because it kept all of its gas. Right, yeah.

Okay, so that's out. The upper end of that's out.

Upper end's out.

I don't know how low we can go, right, because we've got moons that are possibly good places to live, right?

Well, our moon is one-sixth gravity, right?

Right. So that's not going to kill you.

It's not going to kill you. You're going to get some help, right?

But you don't want to get used to it and then come back to Earth. I was going to say, yeah, I mean, three generations later, you know, you have the bone density of a marshmallow.

But you've got the spacesuit, right, that, you know, it's a souvenir, right? All I got was this lousy spacesuit, right, when I came here.

You're not going to be bound for my souvenir shop anytime soon, are you? It's okay.

So, I mean, I think, you know, down on the lower end, it's hard to say how low you can go. It is interesting, though, that when we look out at exoplanets, we find some where there are these little planets that actually end up just getting evaporated away. So instead of their atmospheres being all that evaporates, you got just like crumbly planet going off into space, right? So you got the wrong conditions there. So it's not just the size of the planets, how close it is to the star and everything else it's feeling so.

It probably feels tidal forces that'll disrupt.

If you get the right truly too yeah.

Okay but when when they say super earths we've heard this that's right bigger than earth planets and nothing how big is super.

Bigger than earth right smaller than neptune right so you think like that's in between so you might be.

Twice your gravity something like.

That right we talk about it in terms of the radius of it so how's the size of it because the super earth right it could have a surface it could be a little bit more puffy Okay, but.

So how big a radius compared to Earth if.

It's a super Earth?

Depends on your definition, right? So a few times.

A few times, yeah. Okay. A few times. That's pretty big.

That's pretty big, right?

Normally when people think of, oh, it's twice the size, but if you can range 10 and 100 times bigger, a factor of two is just friendly.

Yeah, exactly.

I mean, we have a poster that we made of people skydiving on a super Earth because they thought, oh, that'd.

Be fun, right? Yeah. We'd be falling faster. Right.

I personally don't think it would be fun.

A lot faster, yes.

But our art team thinks it's great.

Yeah, no, okay.

I think that's great.

But, you know, there was also the question in there of the density, right? And I definitely want to be on that ball of rock rather than that ball of gas like Jupiter because I like.

Having a surface.

You like to want to land somewhere, okay. Yeah, and so, but what if, like, when they, when we retrieved, you know, part of the asteroid, right, we were able to do so because we put the drill down in a place where we knew It was crumbly rock. So what if we know that it's a super earth, but it's kind of made of that kind of that composition of crumbly rock?

I mean, I would love to get to that point, right? Right now, I'm just like, it weighs this much. It seems this big. Divide some numbers.

I don't think that's a real thing. Really? Yeah, because if it's big enough, it has a strong enough gravity. Right. It'll condense. The problem with the asteroids, they don't have much gravity. So they're like loosely, they're loose. Plus it didn't drill. It was a touch and go. It was bang, and then it sucked up. Grabbed whatever popped up in it.

Whatever came up inside of it, yes. And they were ready for just a couple ounces, they got half a pound. Half a pound, so they were good. But no, you're right, the gravity makes sense. And we gotta be a.

Planet, right? Gotta be a planet.

I live to have you say, you try that. I'm sorry. You try that. I was just like, you know what, Neil, you're right. All right, we've got time for like one and a half more questions. One more. All right. Okay, let's go with Andrew Nisker. And Andrew says, hello from Flesherton, Ontario. Can you please explain the different types of biomarker gases?

How will the next generation of telescopes enhance our ability to study exoplanets? Guess that's two separate questions, but hey, I'm always looking up, so I have to ask lots of questions. Nice.

So picking up on the earlier question, you mentioned water molecule, methane, and carbon dioxide.

Right.

But is there like the greatest hits ever of what would reveal life on the surface?

I mean, there's so many different ways that we can search for exoplanets with life, right? Those signatures, right? We call them biosignatures or technosignatures. even want to go a little further afield. And so the fact that, you know, you could look for pollution on a planet, right?

That'd be a techno signature.

That, well, depending on how you count it.

Yeah. Right.

But I mean, like you look for chlorofluorocarbons, right? From your, you know, hairspray on your alien world.

Okay.

You know, that would be a slam dunk for life, even though it's not one of the things we've historically always studied.

Right.

These sorts of things. And so, you know, signatures like methane.

Wait, so the chlorofluorocarbons, they're idiots, right?

But they're idiots we can see, right?

Exactly. They're getting rid of their ozone layer. Which is probably what they're saying about us when they actually see the biomarkers from this planet, or the technomarkers from this planet.

Right, I mean, it's like, if you were really smart, would you want people to see you?

And find you. Right, right. Phosphate was one of them?

So phosphine is something that people have talked about possibly.

No, no, it's all good. It's all good.

Being detected possibly in Venus and whether that's a sign of life or something else is probably something else there. But I think there are lots of detections of all of these more complicated molecules, right, where you start putting things together.

That would be there only if you have life on the surface.

That could be caused by life, right?

Like the chlorofluorocarbons would only be caused by life, but methane could be common from something else.

Okay, because you can get naturally occurring methane. Right, yeah. So what about oxygen?

Oxygen could be there.

I don't know how you get oxygen unless somebody's making it, like with plants.

I mean, like, look at the history of the Earth, right? For billions of years we've existed, and we didn't have this much oxygen all that whole time, right?

Like, go back in time.

So you not only need to look at that planet and just see what it is, but at this particular moment in time.

When I saw the original Star Trek, do you remember that in the original Star Trek, no one ever wore a spacesuit?

No.

They didn't wear a spacesuit? They never wore masks or anything?

You know why? Because they would establish... oxygen nitrogen atmosphere captain let's go on down.

It's a class M planet right exactly breathable atmosphere which I'm thinking oh if you just look hard enough you find other oxygen nitrogen planets and then I realized later that you're only getting the.

Oxygen from living matter on the planet it's not just some random mixture right in the random assortment of planets. Somebody's making the oxygen and on Earth it's our plant life.

But I mean, we can also, you know, when you form a planet, you got all kinds of chemistry going on in there and things going into the rocks. And so what goes on in your atmosphere, some of that just happens naturally.

Okay. So you're going to have to distinguish those cases.

So getting the list is one thing and then you fight about whether it's biological or not.

Exactly. Yeah, at the conferences.

Yeah, that's good. That was a good question. Chuck, time for one half a question. Oh, my God. Let's see. Let's go with Captain James Riley, who says, hello, everyone. Texas here. Is there a most common atmospheric composition out there among rocky planets? I like that.

That's related to that last question.

Super-Earths _ Evaporating Planets with Anjali Tripathi _ Neil deGrasse Tyson

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