The Search for a New Earth

all sorts of squash buckling, princess laden adventures. And uh, it's a fun flick. I recommend people see it if that's the kind of thing you're into it into McNulty from The Wire shows up as the villain, which is fun.

But but but what really got me thinking and how it ties into this podcast is that it really calls back to an age when the science fiction of the day uh is emerging from this idea that Mars could conceivably the habitated world, or a world that had been habitated by a a civilization, not just some organism living deep in the soil, but it could have had civilization on it. In the past or even in the present. And it's just amazing to think back to that time.

It's and and and try to imagine that being possible in your mind. Whereas today we have this, Uh, we know that Mars is virtually lifeless and if even if even if it has life in it, it is Uh, it's not cities, it's not things that can think in a way that we understand, you know, it's not it's not that that vision of swashbuckling adventure that Edgar Rice

Burrows had. Instead, we're we're looking even farther out. We're we're looking, we're having to cast our dreams even farther to try and imagine other worlds that could be like Earth, because that's it's kind of a simple thing. We kind of want on on this very basic level. We want to find that other Earth. We want to find our twin out there in the galaxy. And no, that we are not alone. Right, That's always been the other question, right, are are we alone? Um? You know, is there extraterrestrial

life out there? Um? We've talked about even SETTI, the organization that is committed to trying to find a form of life out there. And as you said, it's really interesting to think that at one point all of this just sort of existed in our minds, this idea of what is out there in the cosmos, not really knowing, not having the sort of data or the technology to substantiate um are our theories. And you know, we just talked about Prometheus and we talked about how they were

journeying to an extra planet or an extrasolar planet. The idea that it's just it's a planet. It is encircling another star, which is not despite what you see in Star Trek and and everything, it's not not in every and not every star is going to have planets, right right, an extra planet too, I mean the planets beyond our

solar system. This used to be just a theory as well, right, So it's it's in context of of thinking about seventeen years ago, it's pretty amazing that we know what we know now, and it does the question now doesn't isn't are their exp planets? The question is where is that earth like planet and doesn't contain life. That's that's where

we're going towards now. Seventeen years ago that we're looking back to hubble Right and cast Star gaze out outward into the stars and was able to identify what planet candidates based on distance stars. Well, first of all, they identified two hundred billion star systems, so this was news. It wasn't like, hey, here's our solar system and then

nothing the two hundred billion star systems and um. And they did this by gathering light for hundreds of hours and staring into deep space and taking all these calculations and figuring this out and it was amazing. So then they took that information and the Kepler mission, which we'll talk about a little bit um, was able, as you say, to identify twenty three hundred UM possible planets extra planets. We say possible because we don't know enough information about

and actually call them planet candidates. And they haven't made it past the candidates, and they haven't made it passive. Yeah, they haven't been vetted yet. But of these we know the dimensions and weight of two hundred planets, okay, and um, we actually have the composition of atmospheres for twelve planets.

This is amazing stuff. And we're particularly interested in those planets that fall within that habitable zone, that sort of goldielike zone, because you look at our planets we have and we went into this on the Stuff to Blow your Kid's Mind video series. You have you have Venus, which is uh to have to have the atmospheres to pressurize, and it's too hot. You go over to Mars, you know, a little far too far to the right, and you

find not enough atmosphere and intense cold. But right there in the little Earth, it's just right the we live in this golden zone. Yeah, we evolved, lack is evolved as we know it to exist within these very slim parameters that we're specifically talking about the orbital distance from a star where liquid water on a planet could exist. That's just one of the things that needs to be going on UM. So yeah, I mean, we we now

have seven hundred confirmed exoplanets UM. Just out of that all the other data, I just want to mention that we do have seven hundred confirmed exoplanets UM and it's amazing that we're at this point in the Kepler mission is actually looking at a tiny region of the Milky Way, in a very small fraction of stars in the galaxy UM. And because the stars are being sampled by Kepler, are very similar to predominant types of stars in the Milky

Way galaxy. Uh, we are getting basically, in a sense, just narrow little pencil beam of stars that may or may not be earth like or that we discover. So that perspective is pretty mind blowing in and of itself because it's just that tiny little point that they're looking at, and what else could the universe contain beyond that? So, like I mentioned before, like every solar system is not going to be a situation of oh, we have planet one, two, three, four,

and five around a single star. You have, it's not gonna look like ours per se. You have a variety of exoplanets in a variety of solar systems. Right. You have planets that are orbiting multiple stars where you would conceivably have if you had a planet you could stand out in that system. You might have to. You would have two sons in the sky at the same time or at different times, depending on how things are, how

the celestial mechanics are panning out. Um, you have planets that don't orbit stars at all, which sounds kind of crazy to just kind of rogue. Yeah, it's just on their own. Um. And then you have at least one that is is areas styrofoam. Yeah, yeah, And this is what they're calling the planetary zoo because they're talking about that the variety of planets that they're discovering and their

atmospheres and their their weights and dimensions. And it turns out that there are smaller, more smaller plants and then there are large ones at least in the area that they're looking in. But it does point to this diversity and this idea that things don't always work the way we think they do, and so we probably need to reframe the way that we're approaching things sometimes, and we may even need to reconsider what the habitable habitable zone is.

A super Earth is basically a planet that is more massive than Earth that is still expected to be predominantly rocky. And that's something that we want right when we're talking about an earthlike planet, we want it to be rocky like ours and not gaseous and hot. Um. And this is a quote from Sarah Seeger. She is um an amazing UM speaker, and she's actually an astrophysicist and and um a planet hunter. Her say, and she says, the diversity of exto planets has really forced us to reconsider

what the habitable zone really is. For example, some of these super Earth's are massive enough that they could retain a different atmosphere than we have on Earth. These super earths may hold onto the light gases hydrogen and helium. In this case, if they have a massive atmosphere, they could have a massive greenhouse effect. So this could actually increase the range of habitable zone in a planetary system. So it's a little bit different than what we've thought of.

We thought, Okay, you have to have the exact conditions that we have here on Earth. There's this I can't help but think, and I imagine some of our listeners are probably thinking of this as well. There was a there was a PC game back in the day called Masters of Orion. They did two of them. Oh they did third one that was supposedly not that good, But they did two of these things, and it's uh. We have different space faring races, and you're exploring new systems.

In each system you discover will have a range of planets, and some of them will be too rocky, someone will be gases only some of some of them can be colonized with a certain extent and others not so much. And a lot of thought. Wind of the game is a very smart early um computer game, but but even even it managed to feel like it misses the mark

and just the vast variety. Because if this game of Masters a Ryan lined up with what we know now about the layout of of other solar systems and the existence of extraplanets, you would encounter a lot of these systems that we just have nothing in them, right, yeah, yeah, again, you know, we have this idea that you know, other solar systems were supposed to be like ours, but yeah,

they're vastly different. Some of them are spinning in what we think of is the wrong direction, um, like Australian one that don't really a line up to the science all that well, but but still backwards rotating solar systems. Yeah, yeah, So actually I was just thinking, like, how cool would it be if they had a planetary Zoo Tycoon game similar to sort of what you're saying. If you've ever played Zoo Tycoon, you know this is again another way to to think about well at least start understanding of

what's out there. It would be very interesting. Yeah, if they if they took that sort of that basic expansion and colonization computer game model and really made it match up with with what we know now and what the conceivable uh near to long term future of of exploration is. I'm just thinking, you put some really cool graphics of like pandas and giraffe planets and get kids to sort through the data for you. You can have like a million kids playing these games and inadvertently like punching some

data for you. It could it could be a win win um. Alright, So here's the question, how are these far flung planets actually inferred? How do we know that they're out there? We suspect they're out there. They don't actually say definitively out there, they say inferred. Well, you have two types of detection. Basically, you have you have direct detection and indirect detection, all right, Um, With direct detection detection, and it's one thing to detect a star,

but it's another thing to detect the planet. The visible light output by a planet like Jupiter is one billion that of its star, but if you shift into the infrared spectrum, the contrast is merely a few thousands, all right, So it helps to to shift the shift out of that visible light spectrum. You can also block out starlight and just focus on the corona, that outer plasma region of the star's atmosphere, and then you can catch the

shine of the planets. Um. Direct imaging is the only way to access some of the really important qualities of an exoplanet, like how much water it has on its surface. But then there are these indirect detection methods, and some of these are are are pretty pretty crazy, like uh another crazy that they're they're really they're really fascinating because it's not a direct method of detection. You kind of have to find have to find a work around to

detect the presence of this planet. Yeah, are you talking about the biosignature gasses. Yes, that's one of the methods that pops up. UM. I love this because it's like a game of clue, you know. Um. This is where different chemicals absorb or they take a bite out of the photons and light at different parts of the spectrum and can be used as a fingerprint um of the

atmosphere of this planet. So if we imagine the planet, we can run the light given off from it through a machine called a spectrograph, which analyzes the data determine the chemicals and the planet's atmosphere um some chemicals which science is called biomarkers. Biomarkers may hint at life on a planet. At least, that doesn't mean that there's life.

It just means that if you have certain chemicals that are taking a bite out of that light spectrum and you can see it missing, then you can start to ascertain the percentages of chemicals in the atmosphere. And I think that is amazing. Yeah, there's also the wheat gravity of a planet pulls the star into the small circular orbit and induces a minute wobble that can be detected using radial velocity tracking, which is which is pretty cool.

And then there's a there's also this scenaria where the planet moves between a star and the observer and the luminosity shifts. There's a that's that's the transit method, and that's actually what the Kepler telescope is using. And just to go back to the Kepler mission, we're talking about basically a giant ninety eight megapixel digital camera that is

taking these photos. Like you were saying, when it crosses the star, you're basically going to see um that a little bit of the light is blocked out and then the camera will measure a dip in the star's brightness, and if a planet is really what's causing that dip, it'll come around and cause the same kind of dip again and again and again. So a lot of this is pointing toward this idea that you have to have a ton of patients if you are a planet hunter. Yeah, because,

like I said, it's one thing to find a start. Um. We can sometimes detect things like black holes, for instance, or potential black holes with gravitational lensing, where we see the way that the mass of an object causes light to bend around it. Well, then there's gravitational micro lensing where you're kind of you're you're you're observing the way

that the star is causing light to bend. But then you're also on top of that observing the way that that stars planets are adding, uh, in a smaller sense to the bending of that light. Yeah. What I like about this too, this planet hunting, is that it kind

of pulls in so many different disciplines. And you have astrophysicists, physicists, you have astrobiologists who are really interested in trying to figure out what the atmosphere looked like in the early days, because having that sort of data can help us then look at another planet and say, well, this could be an earth light planet perhaps in four billion years, because it really matches what we think the Earth look like back in the day um or maybe it's halfway to

that point or so. It's really interesting that everybody is sharing all of this data and trying to to get to the to the answer to the question, which is is there another Us out there? Yeah? And you mentioned clue earlier, and I keep coming back to that because because it's kind of like this, it reminds me a lot of high tech movie TV show crime scene where you have like people are coming in. You have your botanists that are looking at what what what plants are doing?

You have you know, biologists, you have entomologists coming in, think of for an experts, people are shining lasers. All of these different disciplines are coming together, all of these different technologies coming together to put a face on this question mark you know, where who is the killer? And uh? And we see a similar thing here with it with the question mark being is there another Earth? Is there

is there another planet out there that that resembles us? Yeah, and I like that that you pointed out that way that is sort of backing up into the equation and taking all that data and trying to reconstruct the crime scene or the scene of the life, I guess, the scene of possible life. Um, let's take a quick break and then when we get back, we'll talk about trying to find a true Earth twin. So we're back, and uh, yeah,

the idea of finding a true Earth twin. It reminds me a lot of house hunting because you're looking at potential houses, and some houses are not on the market at all, so there's not even you know, like much like these solar systems or even non solar systems, where there's just nothing resembling a planet, uh that we're interested in. Uh.

And then you have then you have planets. I mean, then you have houses that are either they're either too expensive or you get to look at them and they're just to run down, or or they look good at first, but then you find out that they have some sort of major problem like uh, you know, it's a part of the house is collapsing, or it's uh, it's atmosphere is too heavy and won't allow life to exist. In it that you see what I'm saying here, it becomes this.

It's like the Goldilocks scenario, except with a far pickier Goldilocks and so many more um unacceptable containers of poor it. Well, if you are Sarah Seg, you're the planetary scientists, um an astrophysicists, you do kind of want a mystery house, at least for her. She she says, she that we want to look at an atmosphere in search for things that are unusual. So our own atmosphere is oxygen by volume.

If she says, an alien civilization is looking at us from four light years away, presumably with an awesome telescope, and it knows something about chemistry, then it will know that we have millions to billions of times more oxygen than we should if there were no life on Earth.

So that should be a clue to them. There's something going on here through further synthesis, through the interaction of oxygen and carbon dioxide, that that is not fitting uh in line with what its composition should be, and so we're looking for something that's not right. We're looking in the same way to the murder investigation is ends up chasing after individuals that are suspicious in some way, shape

or form, whose story doesn't quite add up. We're doing looking for that planet with a story that doesn't quite add up. Why does it have this much oxygen? Why was it spotted leaving it's a it's apartment at the three in the morning garbage bag. That's right to fear the planetary dick detective. Then these are the questions that they're asking and UM, And what I think is interesting is that these these seventeen years, so much of this has just been an exercise. And let's let's comb through

the data and let's try to take measurements. First. That was the first thing that they wanted to do. Can we take measurements of these planets? Um? The second thing is can we figure out what's in them the habitable zone? Can we start to really figure out whether native? Are they hot and gassie or they rocky? And then it became well, let's really see what's taking a bite out

of the atmosphere here. Let's see if if the composition can give us um a clue as to an earth like twin for us And now Seeger and obviously others in her labs are looking much more specifically at that data set that Kepler has given them, those twenty three hundred planetary candidates, And she is actually helping to build a prototype nano satellite that will be launched in and she says that instead of looking at a hundred and fifties six thousand distant stars, we hope to survey the

very nearest sunlight star for transitting Earth sized planets. So the return to studying individual extra planets will be for those orbiting stars that are close enough for detailed follow up. So they just keep honing in more and more on this idea that we can answer this question in this generation, and then coming in ten, we have a James Webb telescope which is going to just even look more laser

focused at those habitable zones. Yeah, and Singer was on a panel at the World Science Festival about exp planets along with Natalie to Halla. She's a physicist and team leader the Kepler YEP, and that Mountain, the director of

the Space Telescope Science Institute. Now, they all it was a very spirited conversation and they all had different ideas about how to go about planet hunting, but I think they all degree agree that UM this is something that is going to happen in our generation, and they're pretty much hamstrung by the technology. Now they could do it. They could find an earthlike planet if they had every dollar at their disposal, because they could build the right

sort of UM instruments to do this with it. But they are saying that it's very hopeful that you have space X, that you have asteroid mining and basically some private companies coming in and creating the technology which will allow them, just like the nano satellite that seekers working on, to really get in and study it much further. And it's I think it's just really exciting time to know that, um, you know, again, this earthlike planet might be identified, Would

we travel to it? Would there being aliens that consume us? I don't know. Yeah, it's I think I've missed this before, but things like this kind of remind me of of that day when I first started out stuff works and the news head hit that some guys in World, Georgia had a cooler with a big foot in it, an actual dead sasquatch, And for a split second there I was kind of like, is this really going to happen? Is this really gonna turn out to be Bigfoot, and

of course it didn't. But but there was a moment there of possibility, and with our search for exoplanets, that moment of possibility continues to to draw out. Um, you can draw out to the point where some people perhaps lose interest in it and they just tend to think, oh, well, I guess the rest of the universe is empty because

we haven't found uh, that magic planet yet. But you know, some people would say that there are a lot of fish in the sea, there are a lot of planets uh out there in the universe, and if we look long enough, uh, we will find it. Well. And what they said on the panel is if, if, if anything, scientists are patient and they will come for the data and they will find that needle in the haystack. It's just a matter of time, um Seeker said. And I

thought this was interesting. If you want to look back to what we remember hundreds of years ago, inevitably it is the great explorers, Christopher Columbus didn't know what he was going to find, and he came across North America. Many of us working in the field of exoplanets believe that thousands of years from now, when people look back at our generation in the early twenty first century, they will remember the discovery of other earths as one of

our most significant accomplishments. That is the beginning of what's out there? What are the what are the planets? Known? And in the future, we hope that our descendants will find signs of life. I don't know, Yeah, there you go. Um. I certainly hope to see it, and I think that would just be a super exciting thing. Yeah, I think it would be tremendous. And again, it's what I love about stuff like this is that it forces us to recast our understanding of the universe, universe in our place

in it, and we've talked a lot about that. So if it comes to fruition, that's pretty awesome. Coo, Well, let's call the robot over. We well, we didn't call him over in the Prometheus episode because it was super long and all, so we had some some rather complex thoughts to convey about the nature of AI and yeah, basically you boot him on the room because we didn't want to give him any funny ideas about how he could emulate David. So all right, let's see what we

have here from listeners. Well, this one was exciting because we got hats. We did. Some of the podcasters also received these and like them. We will will have to get a snapshot here of us wearing them. But we heard from Adam. Adam wrote in to say, first I have to say I've been a lawyer a lawyer. I've been a loyal listener since the stuff you missed in science class days um, and you actually read a listener

of feedback. I wrote about the oil industry on the Old Show, how it's not as luxurious as the rig on the rigs as people think, though the platforms are nicer. As an engineer out of practice, your episodes captivate the inner scientist and geek within me. Thank you for that. Switching gears. For the past ten months, I've been traveling through Latin America on what I call the Happy Nomad Tour.

After being miserable quote unquote living the dream of living working in worry free Denmark for a wind power company, I finally started asking myself what my passions are, what my dreams are, and what I want out of life. I call this process the happiness plunge um, which also sounds like maybe like a novelty dessert that you would get. I can't throw yourself back into a refreshing pool of tea, but as anyway, he continues, MY goal as a traveler is to leave each place better than how I found it,

which I do by volunteering everywhere I go. I've had volunteering experiences such as feeding the elderly at nursing homes in Mexico, installing solar panels and rural hunduras, attracting book donations for a rural library project in Peru, playing with kids at orphanages in Costa Rica and Ecuador, designing a financial strategy for a new NGO in El Salvador, and marketing an organization that turns donated to use bikes into

bike machines, washing machines, blenders, water well pumps, etcetera. In Guatemala. There's a lot I can offer as an engineer NBA. I listened to quite a few hs W podcast on my ten to twenty our bus rides and wanted to, in a very small way, thank you for what you've given me. Peru is my last stop in Latin America, and I thought these all pack out wool Julio's Julio's feel there's one pronunciation different pronunciation to me, then we'll call him Julia. We're a great way to say things.

And no, it doesn't get too cold. I know it doesn't get too cold in Atlanta, but still I wanted to protect those knowledge filled noggats. I'm at home now, visiting my family and preparing for the Asian leg of the Happy Nomad Tour. I look forward to listening to you guys on the other side of the planet very soon. Once again, thank you for all you've taught me. I

hope you know how appreciated you are. You're super fan Adam, and he also shares a couple of links here, um Happiness Plunge one word dot com that's the website for this and crazy Hair Fundraiser dot com Crazy z Hair fund Raiser h A I R not h R e Um. Yeah, thank you, Adams. Really cool. Actually, even though it's eighty six degrees in Atlanta today, I was wearing my hat this morning, so I appreciate that, and I appreciate your thoughts. Yeah, and it really it sounds like, I mean, it's an

awesome thing that you're doing, so yeah, keep it up. Yeah, I mean, gosh, some people take off little time rest, do you your you're no? Uh low fer there, I'll say that and uh and thanks for the hat. Thanks for writing in. If you guys would like to share something with us, UM, especially if it's the kind of thing you can post on Facebook, you can find us on Facebook, where we are Stuff to Blow Your Mind. You can find us on Twitter, where our handle is

blow the Mind. Let us know what you think about the search for exoplanets. What do you think it's gonna be like the day that that breaks on the local news channel. How is it going to be interpreted by pundits on various cable news channels. I don't know. We'll see what happened shut some thoughts on that will be interesting. UM. You can also send us your thoughts via email at Blow the Mind at Discovery dot com. Be sure to check out our new video podcast, Stuff from the Future.

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