Author Topic: Possible cost-reduction possibilities for the NASA portions of MSR  (Read 90874 times)

Offline Blackstar

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If there is any chance at all of a Mars organism impacting the Earthís ecosystem, dropping a sample through the atmosphere at ballistic speed should not be contemplated. The reality is that smart people know there is no risk, real or imagined.

Planetary protectors are niche Luddites.

Are you one of those smart people?

Offline Emmettvonbrown

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If there is any chance at all of a Mars organism impacting the Earthís ecosystem, dropping a sample through the atmosphere at ballistic speed should not be contemplated. The reality is that smart people know there is no risk, real or imagined.

Planetary protectors are niche Luddites.




Offline jimvela

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Planetary protectors are niche Luddites.

Turns out, the original Luddites were on the correct side of history ( railing against child factory labor, unsafe working conditions, and demanding a living wage- all good things.).

So, perhaps not at all the best reference to make.

Offline Negan

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Plus is able to have a small enough landing range without gps and other guidance.

From what I've researched, Starship will likely use the same terrain relative navigation system NASA uses. There's no reason Starship couldn't use earth reentries to test this system several times for accuracy while having GPS running in the background to make the finer adjustments to have it land on the catch tower and make sure Starship is coming in safely.
« Last Edit: 02/27/2024 02:33 pm by Negan »

Offline deadman1204

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Plus is able to have a small enough landing range without gps and other guidance.

From what I've researched, Starship will likely use the same terrain relative navigation system NASA uses. There's no reason Starship couldn't use earth reentries to test this system several times for accuracy while having GPS running in the background to make the finer adjustments to have it land on the catch tower and make sure Starship is coming in safely.
Would it? That would require JPL giving it to spaceX. Are they even able to? Isn't there alot of proprietary stuff in there? China had to steal the info to enable their landing on mars. Don't think jpl is gonna be giving it away to anyone who wants it.

Offline Negan

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Plus is able to have a small enough landing range without gps and other guidance.

From what I've researched, Starship will likely use the same terrain relative navigation system NASA uses. There's no reason Starship couldn't use earth reentries to test this system several times for accuracy while having GPS running in the background to make the finer adjustments to have it land on the catch tower and make sure Starship is coming in safely.
Would it? That would require JPL giving it to spaceX. Are they even able to? Isn't there alot of proprietary stuff in there? China had to steal the info to enable their landing on mars. Don't think jpl is gonna be giving it away to anyone who wants it.

"NASAís Technology Transfer program ensures that technologies developed for missions in exploration and discovery are broadly available to the public, maximizing the benefit to the nation."

Online DanClemmensen

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Plus is able to have a small enough landing range without gps and other guidance.

From what I've researched, Starship will likely use the same terrain relative navigation system NASA uses. There's no reason Starship couldn't use earth reentries to test this system several times for accuracy while having GPS running in the background to make the finer adjustments to have it land on the catch tower and make sure Starship is coming in safely.
There are several feasible approaches, and SpaceX does not always take the obvious one. For example, SpaceX chose to implement its own IDSS-compatible docking port on Dragon 2 instead of using the Boeing/NASA NDS.

Offline mandrewa

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Note that one of the primary reasons for doing MSR is to detect signs of past life, or at least the environmental characteristics that could have contributed to past life. That is why planetary protection exists, to NOT contaminate the very things you are trying to study. So if you "relax" the planetary protection requirements, contaminate the samples, and then can no longer detect what you are looking for, you shouldn't do the mission in the first place.

I've seen that argument from a lot of people. I have never seen an explanation of why that is true given modern DNA sequencing and genetic analysis capabilities.

I have read a lot about MSR, but haven't really dug into all the planetary protection stuff. Maybe the answers are out there, but I just haven't found them. With that said, I'll explain some of the things that puzzle me.

The first thing is that they do not seem to be taking a lot of planetary protection credit for the sturdy sealed sample tubes. You might think that those titanium tubes would solve a lot of planetary protection problems. However, the no parachute landing ends in a high-g impact which can potentially break the tube seals.

The second thing is that modern DNA sequencing technology is capable of distinguishing biological samples from different individuals of the same species. People are convicted on the basis of DNA evidence. It can also tell different species apart, and estimate how long ago those species diverged from a common ancestor. It seems very likely to me that DNA sequencing could conclusively tell the difference between Earth life and Mars life.

Even if DNA sequencing was not used, there would likely be many biochemical differences between Earth organisms and Martian ones. They quite likely never shared a common ancestor. And differences in the environments would tend to favor different biochemical pathways. There is a precedent for this. In the 1970s in was noticed that some bacteria found in extreme environments had many biochemical differences from others. These differences were so significant that eventually they split the bacteria into two entirely separate groups, the prokaryotes and the archaea.

So I think any contamination from Earth could be easily recognized, and it would be on the surfaces of the Martian rocks and not on the inside.

There are organisms living on Earth right now that could live on Mars as it is right now.

There are it seems to me four possibilities:

a) No life.  There's nothing living on Mars;

b) Earth life.  There are living organisms on Mars, but they are part of the same tree-of-life that is already on Earth;

c) Mars life.  There are living organisms on Mars.  And they are quite similar to life on Earth, ie. chemistry in water, something like nucleic acids, something like proteins, and etcetera.  But the details are different and it will be clear that this life evolved independently on Mars;

d) 'Rock life.' Or in other words some totally alien life that looks like nothing we ever imagined was possible.

I don't think we need to worry about 'rock life.'  It's fantastically unlikely.  And there's nothing we can do to anticipate or to detect such a thing anyway.  We will find it by accident if it exists.

"No life" is fairly likely, but it will be very hard to prove this. How do you prove a negative?

So really what this Mars Sample Return mission is largely about is trying to distinguish between Earth life and Mars life.

If there's Earth life on Mars, we will be able to sequence the DNA, put it on the tree of life we already have, and recognize that it's adapted to Mars because there will surely be substantial differences in the DNA or RNA sequencing.  We should be able to easily distinguish between bacteria or archaea that have been living on Mars for eons from bacteria or archaea that have just reached Mars in the last century.

If there's Mars life on Mars, ie. life that evolved on Mars, then we should be able to recognize this relatively quickly.

It's only in this last scenario that we have a real possible problem with contamination.   If life independently evolved on Mars, then that life will be different and it just might luck out and be really well adapted to some aspect of the Earth.  It might be capable of doing things that life on Earth cannot do.  Then these single-celled Martian organisms might have a profound impact on the Earth.

That's the only part of this that could become a nightmare.

If there's Earth life on Mars, that's not remotely as big a deal.  We would be basically the same stuff already.  There would be no fundamental change of things even if and when there was cross-contamination both ways.

Offline Negan

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Plus is able to have a small enough landing range without gps and other guidance.

From what I've researched, Starship will likely use the same terrain relative navigation system NASA uses. There's no reason Starship couldn't use earth reentries to test this system several times for accuracy while having GPS running in the background to make the finer adjustments to have it land on the catch tower and make sure Starship is coming in safely.
There are several feasible approaches, and SpaceX does not always take the obvious one. For example, SpaceX chose to implement its own IDSS-compatible docking port on Dragon 2 instead of using the Boeing/NASA NDS.

Of course, but that really isn't the point. SpaceX will have the advantage of being able to simulate whatever method it uses in flight several times before it even goes to Mars. Between this and all the data it will have on sonic retro propulsion, Starship will likely be a very accurate landing spacecraft. Legs are another issue, but it's already proven a test regime of low cost hops are a possibility.
« Last Edit: 02/27/2024 02:46 pm by Negan »

Offline matthewkantar

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If there is any chance at all of a Mars organism impacting the Earthís ecosystem, dropping a sample through the atmosphere at ballistic speed should not be contemplated. The reality is that smart people know there is no risk, real or imagined.

Planetary protectors are niche Luddites.

Are you one of those smart people?

Iím smart enough to know there are people who are a lot smarter than I am.

Are you one of those people who attacks the arguer rather than than the argument? Such behavior is not a hallmark of smart people.

Offline deadman1204

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If there is any chance at all of a Mars organism impacting the Earthís ecosystem, dropping a sample through the atmosphere at ballistic speed should not be contemplated. The reality is that smart people know there is no risk, real or imagined.

Planetary protectors are niche Luddites.

Are you one of those smart people?

Iím smart enough to know there are people who are a lot smarter than I am.

Are you one of those people who attacks the arguer rather than than the argument? Such behavior is not a hallmark of smart people.
I'd advise you to look who you are responding to. Thats not a fan boy like most people here. He works in planetary science and is professionally involved in this stuff.
« Last Edit: 02/27/2024 06:37 pm by deadman1204 »

Offline matthewkantar

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If there is any chance at all of a Mars organism impacting the Earthís ecosystem, dropping a sample through the atmosphere at ballistic speed should not be contemplated. The reality is that smart people know there is no risk, real or imagined.

Planetary protectors are niche Luddites.

Are you one of those smart people?

Iím smart enough to know there are people who are a lot smarter than I am.

Are you one of those people who attacks the arguer rather than than the argument? Such behavior is not a hallmark of smart people.
I'd advise you to look who you are responding to. Thats not a fan boy like most people here. He works in planetary science and is professionally involved in this stuff.

I know who he is. He is an authority.

Edit to add: I have respect for him and greatly value his contributions here.
« Last Edit: 02/27/2024 06:46 pm by matthewkantar »

Offline RedLineTrain

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Quote from: RedLineTrain
Which may mean that planetary protection expectations need to be revisited.  It seems counterproductive that even robotic exploration is priced out of existence due to planetary protection expectations.

I think this thread is generally ridiculous, but I'm going to reply to this comment. Note that one of the primary reasons for doing MSR is to detect signs of past life, or at least the environmental characteristics that could have contributed to past life. That is why planetary protection exists, to NOT contaminate the very things you are trying to study. So if you "relax" the planetary protection requirements, contaminate the samples, and then can no longer detect what you are looking for, you shouldn't do the mission in the first place. Doctors sterilize instruments and wash their hands before an operation so that they don't kill their patient with an infection.

That said, planetary protection is a very complicated subject that even the experts struggle to understand. But one of the things that the community has considered is different levels of protection. If you are going to land in a dry, flat area that never had any water, you probably need a lower level of protection than if you are digging up sedimentary rocks that may still have water in or near them.  So the evolving planetary protection concept is as VSECOTSPE characterized it--land the dirty stuff far away from the areas that require the most protection.

My concern is that there does not seem to be solid ground on which to stand in allowing specific Mars activities.  Even if NASA is trying its level best to make a well considered judgment, the tendency would be to make the planetary protection conditions just one step below a sufficient amount to kill the program.  Then we can see that it would be easy to overshoot, and you end up with a dead program.  A backdoor adoption of the precautionary principle.

Offline Blackstar

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Iím smart enough to know there are people who are a lot smarter than I am.

Are you one of those people who attacks the arguer rather than than the argument? Such behavior is not a hallmark of smart people.

Look, let's deescalate this and I'll tell you where I'm coming from.

I don't "work in planetary science." I work in space and aerospace policy, which sometimes involves serving as a study director on planetary science policy projects. Sometimes it involves working on projects concerning biological and physical sciences in space, or Earth science, or near Earth object [asteroid] detection, or astrophysics. I've even done a study on the proper size of the NASA astronaut corps [which included another person who occasionally posts on NSF.] And I sometimes do studies related to the other A in NASA. I don't make any of the decisions, but I run groups of really smart people who make informed, independent, objective recommendations on what the decisions should be in a specific area, and then the government agency involved can accept or ignore those recommendations. So I know some stuff. I know less stuff than I should, and think I know more stuff than I actually do. But I do work in the business.

I happen to work across the hall from somebody who is responsible for doing studies on NASA planetary protection policy, and we occasionally talk. I have never done a planetary protection policy study and I don't want to, because I want to maintain what little sanity I have left.

One of the chips on my shoulder (I have many) is when people have really strong opinions that are not based in fact, but that they believe are based in fact. I often see this whenever the issue of planetary protection policy comes up. Way too often, people state that "planetary protection requires that no germs get to Mars" when that is not the truth.

Let's repeat that again because it is important: planetary protection policy does not require that no germs get to Mars.

What does it require? Well, that's complicated, and it is evolving. But it's worth explaining a bit more. You can go and research what the planetary protection policy is. That's public information. It doesn't require what you and at least one other person up-thread stated it requires. Too often when it comes to planetary protection discussions on the internet what people do is they set up a strawman argument ("planetary protection requires that no germs get to Mars") and then they knock down that strawman argument ("The reality is that smart people know there is no risk, real or imagined. Planetary protectors are niche Luddites."). I've seen Robert Zubrin do this in public a lot and he doesn't know what he's talking about.

Now although anybody who wants to can find and understand the policy, what I would also add is that understanding the actual science and technology of planetary protection is really really difficult. The people who are world-class experts in the science and technology still tie themselves into knots trying to figure it out. One of the problems is that often testing for contamination of a device or a sample risks introducing that contamination. So it's really hard to know if you have thoroughly sterilized an instrument or spacecraft, and testing it might leave contamination behind. That verification process is one of the reasons that a lot of the up-thread discussion about "sterilizing" a spacecraft during reentry or in space is ridiculous, because even if that might work, how do you then test to make sure you have done that?

Nobody who is arguing about planetary protection policy on the internet understands it, and that includes me. But at least I know what I don't know. So that's where I'm coming from. If somebody makes a ridiculous strawman argument in order to knock it down, it gets my Irish up (and I'm only a little bit Irish and the rest is mostly Klingon).


Offline StraumliBlight

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Let's repeat that again because it is important: planetary protection policy does not require that no germs get to Mars.

This slide gives a nice visual summary of the current limits.

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Planetary protection requirements limit microbial contamination to less than 300 spores per square meter on a spacecraft surface.

This Forensics Summit presentation gives a brief overview and how protection will evolve with crew landings.

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Robotic Planetary Protection focus is controlling bioburden
Crewed Planetary Protection shift to managing bioburden

Offline VSECOTSPE

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There are a lot of errors and misconceptions in this thread, but this one is particularly bad. Gusev Crater was the landing site for the Spirit rover. Perseverance landed at Jezero Crater, which is thousands of miles away from Gusev.

Relax.  Itís just a typo or brain fart.  Doesn't affect the substance.  Corrected in the OP.

Let's repeat that again because it is important: planetary protection policy does not require that no germs get to Mars.

I provided a link to the current NASA planetary protection standards in post #259 just a couple pages upthread.  If folks bothered to read and process that document before typing, most of the recent posts in this thread would have been unnecessary.

Like I explained in that post, planetary protection at Mars is no different from what we do on Earth with rare, fragile but scientifically important environments; it leaves lots of real estate for other robotic missions on the surface of Mars; and it does not rule out crewed missions because they simply have not been addressed yet. 

And to be clear, planetary protection is not the biggest hurdle to a SX or other private human Mars missions.  The primary hurdle is that thereís no regulatory home at all for novel private spacecraft and missions and competing White House and Senate proposals about what department/agency  should have that responsibility.

Offline matthewkantar

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Blackstar, I try to be as clear and concise as possible when writing on this forum. Sometimes this may lead to miscommunication. My bad.

The ďsmart peopleĒ I was referring to are precisely represented by your colleague across the hall. If the people tasked with staring at this problem have cleared a mission where Mars stuff is dropped through Earthís atmosphere, ballistically, I seems to me the assessed risk is low. The risk will continue after the samples are retrieved, no containment facility is faultless.

Recklessness is not something I would ascribe to these smart people.  I think we can all agree keeping Mars clean enough for science is a lower priority than keeping Earth safe. If that is true, then the proper thing to do is wait until the samples can be studied on orbit or in situ.

That could be a long time. Could cost a lot of money. Sending the samples back is the fastest, cheapest way to get some answers. What Iím looking for is a consistent approach, no hypocrisy.

Offline Don2

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There are organisms living on Earth right now that could live on Mars as it is right now.
Do you have a reference for that? When talking about organisms surviving on Mars, we need to distinguish between two possibilities. One is that they are capable of growing and reproducing under Martian conditions.  The other is that they form spores which could survive temporary exposure to Martian conditions, but would not grow and reproduce until they returned to more Earth-like conditions. After enough time in Martian conditions those spores would become sterile.

It would simplify the discussion if we focused on the conditions in Jezero Crater. This is not what is known as a special region as there is no ice close to the surface. I would be very surprised if there is any Earth organism which would grow and reproduce under Jezero Crater conditions.

The results of the Viking labeled release experiment raise another issue. They show that there is some unknown agent that can destroy simple biological molecules. Many of the inorganic compounds that have been suggested as explanations for those results are very good at killing microorganisms.

There are it seems to me four possibilities:

a) No life.  There's nothing living on Mars;

b) Earth life.  There are living organisms on Mars, but they are part of the same tree-of-life that is already on Earth;

c) Mars life.  There are living organisms on Mars.  And they are quite similar to life on Earth, ie. chemistry in water, something like nucleic acids, something like proteins, and etcetera.  But the details are different and it will be clear that this life evolved independently on Mars;

d) 'Rock life.' Or in other words some totally alien life that looks like nothing we ever imagined was possible.
There's actually another possibility, which is that there was life in Jezero Crater when it was wet, but that life is now extinct.

It's only in this last scenario that we have a real possible problem with contamination.   If life independently evolved on Mars, then that life will be different and it just might luck out and be really well adapted to some aspect of the Earth.  It might be capable of doing things that life on Earth cannot do.  Then these single-celled Martian organisms might have a profound impact on the Earth.

That's the only part of this that could become a nightmare.

What you are talking about is the kind of invasive species problem which is quite common on Earth. That usually happens when life moves between similar environments. Life adapts to living in a particular environment. When moved to a very different environment, it usually does poorly. I think the Earth and Mars environments are too different for Mars life to do well on Earth. Earth life has had billions of years to optimize for living under Earth conditions. The notion that a Martian life form would be able to out-compete Earth organisms under Earth conditions seems extremely far fetched.

Our oxygen atmosphere would likely be a big problem for Martians. We are not used to thinking of Earth as a poisoned planet with a highly toxic atmosphere. However, when atmospheric oxygen started to accumulate it did wipe out a lot of the life that was present on Earth at that time.

Online JayWee

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Fellow forum members, can we please get back to the topic - how to make MSR cheaper?

Offline mandrewa

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There are organisms living on Earth right now that could live on Mars as it is right now.
Do you have a reference for that? When talking about organisms surviving on Mars, we need to distinguish between two possibilities. One is that they are capable of growing and reproducing under Martian conditions.  The other is that they form spores which could survive temporary exposure to Martian conditions, but would not grow and reproduce until they returned to more Earth-like conditions. After enough time in Martian conditions those spores would become sterile.

No, I don't have a reference.  I'm extrapolating from what I know about anaerobic organisms here on Earth.

Here is an example:

Quote
Candidatus Desulforudis audaxviator (purple bacteria straddling orange carbon spheres) from under Mponeng gold mine in South Africa.

I picked this organism literally at random.  Let's see if it might possibly be able to live on Mars.

It turns out it has a Wikipedia article: https://en.wikipedia.org/wiki/Candidatus_Desulforudis_audaxviator

It was discovered in a gold mine between 0.93 and 1.86 miles under the ground.

It needs water and a particular mix of minerals to live on.  If we can find those same minerals on Mars under the ground, why wouldn't it be able to live there?

Amazingly Candidatus Desulforudis audaxviator gets energy from a radioactive isotope.  As far they know it does not depend on any other organism -- which is pretty unusual as far we know.  It has genes to extract carbon from carbon dioxide, carbon monoxide, and other sources.  It has genes to extract nitrogen from elemental nitrogen and it has genes to extract nitrogen from ammonia.

The people that found this organism believe this population of bacteria has been isolated from the Earth's surface for at least several million years.

Ca. D. audaxviator is a Gram positive sulfate-reducing bacterium. 

Gram positive is about the structure of the cell wall. Sulfate-reducing means this organism get its energy from sulfate.  It gets energy from reducing the sulfate.  How does it reduce the sulfate?

Hydrogen for this reduction comes from the radiolysis of water[5] from the decay chain of uranium and thorium.

So that's the other ingredient that this organism has to have in order to get energy.

Quoting from Wikipedia:

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Ca. D. audaxviator lives in a complete absence of organic compounds, light, and oxygen, in temperatures exceeding 60 įC (140 įF) and a pH of 9.3. The physiology that enables it to live in these extreme conditions is a tribute to its unusually large genome, consisting of 2157 genes instead of the 1500 of "streamlined" bacteria found in very stable environments. If conditions become unfavorable for normal life, Ca. D. audaxviator is able to form a bacterial endospore, safeguarding its DNA from heat, extreme pH, and the lack of water.[6]

Now is there any place like that on Mars underground?

I don't know.  But if there is then this could live there.

I choose that organism at random.  And there are a long list of different anaerobic organisms that live on many different minerals.

What they all have in common is that they all need water in order to do their internal chemistry.


Quote
It would simplify the discussion if we focused on the conditions in Jezero Crater. This is not what is known as a special region as there is no ice close to the surface. I would be very surprised if there is any Earth organism which would grow and reproduce under Jezero Crater conditions.

Well that rules out life.  Everything we have an Earth needs water.  But bear in mind that there are organisms on Earth can wait more than 10,000 years for water (That's approximate.  I forget the number of years.)

Quote
There are it seems to me four possibilities:

a) No life.  There's nothing living on Mars;

b) Earth life.  There are living organisms on Mars, but they are part of the same tree-of-life that is already on Earth;

c) Mars life.  There are living organisms on Mars.  And they are quite similar to life on Earth, ie. chemistry in water, something like nucleic acids, something like proteins, and etcetera.  But the details are different and it will be clear that this life evolved independently on Mars;

d) 'Rock life.' Or in other words some totally alien life that looks like nothing we ever imagined was possible.
There's actually another possibility, which is that there was life in Jezero Crater when it was wet, but that life is now extinct.


Good point.

Quote
It's only in this last scenario that we have a real possible problem with contamination.   If life independently evolved on Mars, then that life will be different and it just might luck out and be really well adapted to some aspect of the Earth.  It might be capable of doing things that life on Earth cannot do.  Then these single-celled Martian organisms might have a profound impact on the Earth.

That's the only part of this that could become a nightmare.

What you are talking about is the kind of invasive species problem which is quite common on Earth. That usually happens when life moves between similar environments. Life adapts to living in a particular environment. When moved to a very different environment, it usually does poorly. I think the Earth and Mars environments are too different for Mars life to do well on Earth. Earth life has had billions of years to optimize for living under Earth conditions. The notion that a Martian life form would be able to out-compete Earth organisms under Earth conditions seems extremely far fetched.

Well, I'm reasoning intuitively here.  This is based on my sense of how life might evolve.

But I wonder if there might be multiple ways for life to evolve.  Each path to an initial viable system might be extremely unlikely, but once you get such a system it pretty much rules another such system developing because the first system will take over the environment.

So it could be that the initial living system on Earth could have been just one possibility out of millions.

If that were the case then we would expect the initial starting point on Mars would be something completely different. And that difference would persist in all subsequent organisms that evolved from the initial starting point.

And these different initial starting points could have far reaching consequences so that because of the different starting point the Martian life could by chance be preadapted to some environments on Earth.

Quote
Our oxygen atmosphere would likely be a big problem for Martians. We are not used to thinking of Earth as a poisoned planet with a highly toxic atmosphere. However, when atmospheric oxygen started to accumulate it did wipe out a lot of the life that was present on Earth at that time.

It seems unlikely that an organism from Mars could tolerate oxygen.  But there are many places on Earth that don't have oxygen.

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