Is There Life on Mars? NASA's Discovery Explained by an Astrophysicist and Microbiologist

Alright, so let's go back out to space a little bit. Let's do it. Let's go to the red planet. Because we are recording this on September 10th. Right. And there has been an announcement from NASA. And let me read this. It's a quote. Yeah. Just a few hours ago NASA had a big press conference saying they've discovered what I quote very well could be the clearest sign of life that we've ever found on Mars. Hmm. Let me catch my breath. Yeah. Take a deep one, bro. Seriously, like clearest sign of that is those are clearest sign of life. Like I would be happy with a sign of life. There are pictures. Yeah. Right. What NASA points out in this image is something called a leopard spot. They circle this rock and say leopard spot. So I'm guessing they're not saying that a leopard spot fell off a leopard on Mars and now it's right here on the ground. Right. It's some sort of mineral signature. So what is going on with the leopard spot that seems to make it the clearest sign of life yet? Yeah. Yeah. So understandably, NASA scientists like the rest of us, you know, we give these things nicknames. And so if you look at the photo, you can see that it's got these speckles. Right. And it kind of looks like the spots on a leopard. And this is it looks like a sediment deposit with different kinds of minerals sort of sprinkled in there, if you will. And what's really exciting is that those minerals have very different chemical properties. And so on Earth, you don't usually find them next to one another unless some microbe has been involved. And I want to underline the word usually. Usually. Right. So this, I would not read this as a smoking gun that there was a microbe. But what it does suggest is that like here on Earth, when we see these different kinds of minerals side by side, that chances are there's some microbe that did this. And in the case of Mars, there was a microbe that did this in the past and this became preserved in this sediment. That's what's exciting. That's why the NASA scientists who are publishing these data are like this smacks a bit of what we see microbes doing on Earth. So in this particular sample that NASA has produced. Yeah. Why is it that them being in proximity? I get it that they're in proximity, but why does life put them next to each other versus a non-living scenario? Yeah. One of the things that I've been alluding to is this idea of life out of disequilibrium and disequilibrium from the environment. So what I mean by that is we know, for example, that there are microbes on Earth that are in the deep ocean sediments. When you get a few centimeters or a meter or so into the ocean sediments, oxygen's gone. So there's no oxygen, di-oxygen. There's no oxygen gas dissolved in the water. In many of those places, there's iron oxides. Just call it rust, generically speaking, different forms of it. But there are microbes that can take that rust and they can breathe it. The way you and I use oxygen gas, they will breathe that rust through a really cool process. And in so doing, they will produce non-rusty iron or iron two. And that's often soluble, but sometimes it reacts with elements. And I have a buddy, Brandy Toner in Mississippi. She loves this stuff. She's good at it. And what she does is uses really cool probes at the synchrotron facilities, these places where you can zap things. And she looks for different mineral phases. And if you've got a rust sitting next to a non-rust, unless it's in a specific place like a vent, if you've got that sitting in deep sea sediments, there's a good chance a microbe did that. Oh, it's kind of like with uranium decaying into lead. Yes. You see this? Yes. Right. And so this particular combination smacks of some microbe breathing this oxide and turning it into making this iron two. That's why the Mars, the lead scientists were excited. Because this is, we see bits of this on earth. Right. So for these particular minerals that they found on Mars, where do we find the same minerals side by side on earth? Yeah. It's like, it's again, it's the same. It's underwater hot springs. It's deep sea sediments, right? I see. They're iron containing minerals. Yeah. And it looks like a microbe could have been breathing one and producing the other. Is it always deep sea? Because on Mars, Jezero crater is sort of like a, my understanding has like a river delta type situation where water was flowing into a crater lake. Yeah. Great question. It's not always deep sea, but the reason on earth, it's often deep sea is because we have this atmosphere full of oxygen. And the moment a microbe on the surface takes say rust and turns it into this non rusty iron two atmospheric oxygen messes with it. Right. Does that make sense? That does make sense. Right. So, so this, so this signature is more likely to have occurred before we had oxygen in our atmosphere. Right. Or today in anoxic. In anoxic environments like underneath the sand. Right. Because you build up that rust on the sea floor, it gets stuck in an anoxic environment and then a microbe messes with it. Right. Yeah. Yeah. So here's what I think is cool. Here's where I agree with NASA. This leans towards something less usual, unusual. It's something unusual. And so it means that these minerals which are Vibionite and Grigite, if I remember correctly, the fact that they're near each other is similar to what we see here on earth. So it's, it's, it's sort of circumstantial. Circumstantial evidence. Yeah. But it's cool. Yeah. Yeah. It's a good place to look. Yeah. Yeah. It's a step in the direction of finding life. Right.