Adam Frank
speaker
594 appearances
1 recordings
1 series
first heard Dec 2024
last heard Dec 2024
Adam Frank’s voice in public audio — every appearance, attributed to the second.
Trend
recordings per month · last 12 monthsNo recordings in the last 12 months.Older appearances are listed below; set an alert to hear about the next one.
Appearances
This process of SETI. I have to put on my scientist hat and just say, my gut feeling is that dumb life, so to speak, is common. I am a little agnostic about, I can see ways in which intelligent civilizations may be sparse. But until you know, we got to go look. It's all armchair astronomy.
Yeah. Yeah. The potentially dead part, I think, right. It could be that like making civilizations is easy. They just don't last long. So what we, when we went out there, we'd find a lot of extinct civilizations, extinct civilizations, uh,
Yeah. So SETI, search for extraterrestrial technology, is a term that I am not fond of using anymore. I mean, some people in my field are, so I'm sorry, folks. But what I really like is the idea of techno signatures because I think – To me, SETI is the – first of all, intelligence. We're not really looking for intelligence. We're looking for technology. I mean, you know.
And SETI, the classic idea of SETI is the radio telescopes, you know, and contact, Jodie Foster with the headphones. That whole thing is still part. It's still active. There's still great things going on with it. But suddenly, this whole new window opened up. When we discovered exoplanets, we now found a new way to look for intelligent civilizations or life in general –
In a way that doesn't have any of the assumptions that had to go into the classic radio setting. And specifically what I mean is we're not looking for somebody sending us a beacon. You really needed that with the classic model for a bunch of different reasons. You have to assume they wanted to be found and they were sending you a super powerful beacon.
Now, because we know exactly where to look and we know exactly how to look, we can just go about looking for passive signatures of the civilization, going about its civilizationing business, you know, without asking whether they want to be contacted or not. So this is what we call a biosignature or a technosignature.
It is an imprint in the light from the planet of the activity of a biosphere or a technosphere. And that's really important. That is why kind of the whole Gaia idea ends up being astrobiological, that biospheres and technospheres are so potent, they change the entire planet. And you can see that from 20 light years.
So let's give an example of a biosignature to start off with, which would be a signature of a biosphere.
oxygen right in our on earth at least we know that oxygen is only in the atmosphere because life put it there if life went away the oxygen and particularly oxygen and methane that pair they would disappear you know very quickly they'd react away they'd all be gone so if you find a planet with oxygen and methane that's a good bet that there's a biosphere there Okay, what about technospheres?
Technospheres, this is what, you know, so I'm the principal investigator on the first grant NASA has ever given to do these kind of exoplanet techno signatures. NASA was kind of, for reasons we can talk about, NASA had gotten pretty gun shy about funding anything about intelligent life. But OK, what's an example of a techno signature? Well, one could be atmospheric pollution.
I'm going to put pollution in quotes here because it doesn't have to be pollution, but gases like chlorofluorocarbons. So we've dumped, you know, we dumped a huge amount of chlorofluorocarbons into the atmosphere by mistake. It was affecting the ozone. But we put so much in there that actually this is one of the things we did.
We did a paper where we showed you could detect it across interstellar distances. You could look at the atmosphere, look at the light coming from a distant planet and pass the light through a spectrograph and see the spectral lines, the fingerprint, the spectral fingerprint of chlorofluorocarbons in an atmosphere.
And that would for sure tell you that there was a technological civilization there because there's no other way to make chlorofluorocarbons except through some kind of industrial process.
I wouldn't necessarily call these anomalies. I'm looking for things that, for biosignature, I'm looking for things that a geosphere, right, you know, that just rock and air wouldn't produce on its own. What kind of chemicals would life produce? Right, and that's part of the, that's the interesting thing, right? So that's what, you know, so we can use Earth as an example, right?
We can say, look, oxygen, we know there would be no oxygen in the atmosphere if it wasn't for dimethyl sulfide, which is a compound that phyloplankton dump into the atmosphere, a lot of it. That's sometimes mentioned. And there was even, there was a paper that somebody wrote where it was like, well, we're not saying we see it, but, you know, there's a bunch of noise in the spectra right there.
So, you know, there's a whole list of things that Earth has done that are in the atmosphere that might be biosignatures. But now we're reaching an interesting point. The field has matured to the point where we can start asking about agnostic things. biosignatures, things that have nothing to do with Earth's history.
But we think that that would still be indications of this weirdness we call life, right? What is it in general that life does that leaves an imprint? So one of these things could be the structure of the network of of chemical reactions, that biology always produces very different chemical networks, who's reacting with who, than just rock and water, right?
So there's been some proposals for networked biosignatures. Information theory, you can use, you can try and look at the information that is in the different compounds that you find in the atmosphere. And maybe that information shows you like, oh, there's too much information here. There must've been biology happening. It's not just rock. Same thing for techno.
That's what we're working on right now. That for techno signatures as well.
Okay. So with technosignatures, I gave the example of chlorofluorocarbons. So that would be an example of, and again, that one is a non-agnostic one because we sort of like, oh, we produced chlorofluorocarbons. Maybe they will, right? And there's solar panels, right?
Showing 201–220 of 594 · page 11 of 30
← Previous
Next →