Astrophysicist here. I've always found it striking that back in the 1970s, the first Viking lander on Mars carried a suite of life-detection experiments, one of which got a positive result consistent with microbial metabolism (the labeled release experiment). This was dismissed after the same lander's Gas Chromatograph–Mass Spectrometer (GCMS) found no organic material. But, in 2008, further experiments showed that the GCMS could feasibly have destroyed any organic compounds, leading to a false negative.
Gilbert Levin, the PI of the labeled release experiment, maintained his whole life that his experiment did find evidence for life on Mars.
I'm amazed that in the half-century since Viking, these results have never really been followed up. The community seemed to conclude that there was no evidence for life on Mars and stopped trying. It's only in the last decade, with our new ability to detect bio-signatures on nearby exoplanets, and with the hint of phosphene on Venus (etc) that the idea has started to seem less crazy.
With these new findings, I wouldn't be surprised if it turns out that Levin was right all along. Exciting times! But as you say, we need a serious sample return or crewed mission to get to the bottom of it.
Really liked this line: “Maybe this helps people contextualize it: If this exact same evidence had been found on Earth, the conclusion would be straightforwardly biological, and an abiotic explanation would be taken less seriously—….”
Makes you wonder what the threshold of proof really is.
Ironically, I think this essay makes a convincing case for why we *shouldn't* send humans to Mars, at least not anytime soon. Right now, like you said, any signs of life there are preserved like a perfect museum. The rovers we've sent there have been carefully sanitized. But it's impossible to sanitize a human mission to such a degree, especially a large, permanent mission.Send more robots- send *lots* of robots- but don't send humans or any other organic material.
And this sentence is odd: "Our tech titans will need to refocus away from winning the race about who can generate the most realistic images of cats driving cars, or whatever." Right now the biggest tech titan of all is Elon Musk, and he's dead set on sending humans to Mars. Unfortunately he seems to want to send lots and lots of regular people there to colonize it, which has the chance to permanently destroy any signs of Martian life, or at least make it impossible to know whether it came from there or Earth.
It's an interesting consideration, and I almost wrote something about it. I think a lot depends on two questions:
1. Would a small human colony on one part of the planet really contaminate the planet, overall? Consider that we can get some evidence from early life here on Earth, after billions of years of such contamination. But I think yes, you're right that, if there was a city on Mars with "1 million people," I'd be concerned.
2. Do we actually have the political will to send robots for the centuries needed, and can they do the science? We just saw a great counterargument to this: supposedly, these samples were supposed to be returned. It now looks very unlikely for that to happen. Despite the up-front expense of a small human starter colony, they'd be able to do real confirmed science incredibly quickly, in comparison to decades of robotic visits.
I don't know the answer to the questions, but I'd be interested in a deeper dive on the contamination issues. How much would it be likely to interfere with our ability to come to firm conclusions? My initial leaning is that it's actually not a deal breaker and basically required to actually find anything out, because of #2, but I'd love to read a deeper dive into someone figuring that out based on the experiments necessary, the likely evidence, that sort of thing.
We need a robotic sample-return mission to Mars. Back on Earth, sophisticated biochemistry analytical instruments can analyze the samples. Let's do this! Sending humans costs roughly $100 Billion - and what tests can mere humans do?
The way that we are doing science on Mars is basically:
-> Have an idea.
-> Plot out 10 year plan to instantiate the idea.
-> Have another idea in response to something that came up from the first idea.
-> Plot out a 10 year plan to check that.
-> And so on, forever.
This is wildly ineffective. That's why I say in a literal day a human scientist could make far more progress. Humans can iterate. That's the massive power of a human being, still, compared to AI and robots. You can go do an experiment, and then you can look at the results, then do another experiment in response to those results. That's what people do on Earth. Even if we got the sample back, we'd basically be confined to just checking the results. In the long run, this sample doesn't matter that much, other than providing more reasons for human exploration (which I think are already good enough).
A human could check, e.g., check abiotic causes around in the area, looking for better or clearer evidence, ruling things out, take different samples quickly, adapt to anything that comes up. And they could do it in days. Right now we can't even *turn over the rock.* A human just, like, plop. Other side!
"You can go do an experiment, and then you can look at the results, then do another experiment in response to those results" Erik - Your enthusiasm is wonderful. However, a human can't do most experiments. Massive, expensive, analytical equipment is needed, such as a PCR to amplify DNA or other replicating molecules, a mass spectrometer to identify molecules and proteins, and culture incubators to grow microbes and analyze them. Look up the cost of a gas chromatograph. And on and on. They must be on Mars. A microscope? A robot can take such images and relay them back to Earth.
I had all those things in my gene cloning lab in college, which I was a TA of, and it was quite humble! A PCR machine is like, the size of a printer now. I looked up the price of a gas chromatograph and it was between $2,500 - $15,000, according to Google. The actual equipment you need for any of this science is very small and very cheap, relatively speaking. These are all experiments that are easy to run, straightforward, and can be done on all sorts of common equipment. The hard part is doing them remotely on another world.
Erik - The start-up cost of a biology lab - for a beginning professor - is $1 million to $2 million. Also renovating the lab space costs ~$1000 per square foot. One also needs 5 to 10 research assistants (e.g. grad students and postdocs) to operate, assess data, and interpret all the results. And that lab only performs one type of analysis. Restricted. On Mars, even the mere construction of the laboratory requires personnel: Excavating ground, building the structure of the laboratory, putting in electricity, water, a clean room, internet, and even air! Where are all the contractors? There are none. Who installs the lab benches, the fume hoods, the vast array of needed chemicals. Who builds the living quarters? And on and on.
All the experiments are easy, no harder than the astronauts do on the international space station. They could be done mostly by a single person. And most labs are not restricted to a single kind of analysis. Again, you could do most of what's required with basically just a couple key pieces of equipment from my old undergraduate college labs. What I certainly agree is that getting to Mars is hard. But 99.99% of the difficulty is precisely that. This is not difficult or expensive science once you are on Mars and have a habitat and a couple pieces of equipment the size of printers.
The point is not just to analyze the sample, but to unify people. I think that's what Eric had in mind. Sending a team to Mars is better in that regard than just getting samples back...
I agree. We humans must go. However, sending humans requires dozens of robotic missions that drop-off life-support. Think Moon: Humans go - and bring back lunar rocks for analysis.
Why does it take more than a small team of scientists? By "let's go" you mean just a few scientists, but everyone starts routing for them as a way to unify us? I have another project that might do the job of unifying us that involves figuring out how to localize our economy and get people to actually depend on their family and community members. It's both a tech project and an organizational project. It would probably be cheaper than getting a team to Mars, and it actually addresses our problems scientifically, instead of trying to distract us from them with this sort of Kurt-Vonnegutesque project.
Astrophysicist here. I've always found it striking that back in the 1970s, the first Viking lander on Mars carried a suite of life-detection experiments, one of which got a positive result consistent with microbial metabolism (the labeled release experiment). This was dismissed after the same lander's Gas Chromatograph–Mass Spectrometer (GCMS) found no organic material. But, in 2008, further experiments showed that the GCMS could feasibly have destroyed any organic compounds, leading to a false negative.
Gilbert Levin, the PI of the labeled release experiment, maintained his whole life that his experiment did find evidence for life on Mars.
I'm amazed that in the half-century since Viking, these results have never really been followed up. The community seemed to conclude that there was no evidence for life on Mars and stopped trying. It's only in the last decade, with our new ability to detect bio-signatures on nearby exoplanets, and with the hint of phosphene on Venus (etc) that the idea has started to seem less crazy.
With these new findings, I wouldn't be surprised if it turns out that Levin was right all along. Exciting times! But as you say, we need a serious sample return or crewed mission to get to the bottom of it.
Really liked this line: “Maybe this helps people contextualize it: If this exact same evidence had been found on Earth, the conclusion would be straightforwardly biological, and an abiotic explanation would be taken less seriously—….”
Makes you wonder what the threshold of proof really is.
Ironically, I think this essay makes a convincing case for why we *shouldn't* send humans to Mars, at least not anytime soon. Right now, like you said, any signs of life there are preserved like a perfect museum. The rovers we've sent there have been carefully sanitized. But it's impossible to sanitize a human mission to such a degree, especially a large, permanent mission.Send more robots- send *lots* of robots- but don't send humans or any other organic material.
And this sentence is odd: "Our tech titans will need to refocus away from winning the race about who can generate the most realistic images of cats driving cars, or whatever." Right now the biggest tech titan of all is Elon Musk, and he's dead set on sending humans to Mars. Unfortunately he seems to want to send lots and lots of regular people there to colonize it, which has the chance to permanently destroy any signs of Martian life, or at least make it impossible to know whether it came from there or Earth.
or in other words: https://idlewords.com/2023/1/why_not_mars.htm
It's an interesting consideration, and I almost wrote something about it. I think a lot depends on two questions:
1. Would a small human colony on one part of the planet really contaminate the planet, overall? Consider that we can get some evidence from early life here on Earth, after billions of years of such contamination. But I think yes, you're right that, if there was a city on Mars with "1 million people," I'd be concerned.
2. Do we actually have the political will to send robots for the centuries needed, and can they do the science? We just saw a great counterargument to this: supposedly, these samples were supposed to be returned. It now looks very unlikely for that to happen. Despite the up-front expense of a small human starter colony, they'd be able to do real confirmed science incredibly quickly, in comparison to decades of robotic visits.
I don't know the answer to the questions, but I'd be interested in a deeper dive on the contamination issues. How much would it be likely to interfere with our ability to come to firm conclusions? My initial leaning is that it's actually not a deal breaker and basically required to actually find anything out, because of #2, but I'd love to read a deeper dive into someone figuring that out based on the experiments necessary, the likely evidence, that sort of thing.
Thank you for joining the choir.
We need a robotic sample-return mission to Mars. Back on Earth, sophisticated biochemistry analytical instruments can analyze the samples. Let's do this! Sending humans costs roughly $100 Billion - and what tests can mere humans do?
The way that we are doing science on Mars is basically:
-> Have an idea.
-> Plot out 10 year plan to instantiate the idea.
-> Have another idea in response to something that came up from the first idea.
-> Plot out a 10 year plan to check that.
-> And so on, forever.
This is wildly ineffective. That's why I say in a literal day a human scientist could make far more progress. Humans can iterate. That's the massive power of a human being, still, compared to AI and robots. You can go do an experiment, and then you can look at the results, then do another experiment in response to those results. That's what people do on Earth. Even if we got the sample back, we'd basically be confined to just checking the results. In the long run, this sample doesn't matter that much, other than providing more reasons for human exploration (which I think are already good enough).
A human could check, e.g., check abiotic causes around in the area, looking for better or clearer evidence, ruling things out, take different samples quickly, adapt to anything that comes up. And they could do it in days. Right now we can't even *turn over the rock.* A human just, like, plop. Other side!
"You can go do an experiment, and then you can look at the results, then do another experiment in response to those results" Erik - Your enthusiasm is wonderful. However, a human can't do most experiments. Massive, expensive, analytical equipment is needed, such as a PCR to amplify DNA or other replicating molecules, a mass spectrometer to identify molecules and proteins, and culture incubators to grow microbes and analyze them. Look up the cost of a gas chromatograph. And on and on. They must be on Mars. A microscope? A robot can take such images and relay them back to Earth.
I had all those things in my gene cloning lab in college, which I was a TA of, and it was quite humble! A PCR machine is like, the size of a printer now. I looked up the price of a gas chromatograph and it was between $2,500 - $15,000, according to Google. The actual equipment you need for any of this science is very small and very cheap, relatively speaking. These are all experiments that are easy to run, straightforward, and can be done on all sorts of common equipment. The hard part is doing them remotely on another world.
Erik - The start-up cost of a biology lab - for a beginning professor - is $1 million to $2 million. Also renovating the lab space costs ~$1000 per square foot. One also needs 5 to 10 research assistants (e.g. grad students and postdocs) to operate, assess data, and interpret all the results. And that lab only performs one type of analysis. Restricted. On Mars, even the mere construction of the laboratory requires personnel: Excavating ground, building the structure of the laboratory, putting in electricity, water, a clean room, internet, and even air! Where are all the contractors? There are none. Who installs the lab benches, the fume hoods, the vast array of needed chemicals. Who builds the living quarters? And on and on.
All the experiments are easy, no harder than the astronauts do on the international space station. They could be done mostly by a single person. And most labs are not restricted to a single kind of analysis. Again, you could do most of what's required with basically just a couple key pieces of equipment from my old undergraduate college labs. What I certainly agree is that getting to Mars is hard. But 99.99% of the difficulty is precisely that. This is not difficult or expensive science once you are on Mars and have a habitat and a couple pieces of equipment the size of printers.
The point is not just to analyze the sample, but to unify people. I think that's what Eric had in mind. Sending a team to Mars is better in that regard than just getting samples back...
I agree. We humans must go. However, sending humans requires dozens of robotic missions that drop-off life-support. Think Moon: Humans go - and bring back lunar rocks for analysis.
Why does it take more than a small team of scientists? By "let's go" you mean just a few scientists, but everyone starts routing for them as a way to unify us? I have another project that might do the job of unifying us that involves figuring out how to localize our economy and get people to actually depend on their family and community members. It's both a tech project and an organizational project. It would probably be cheaper than getting a team to Mars, and it actually addresses our problems scientifically, instead of trying to distract us from them with this sort of Kurt-Vonnegutesque project.