If We Find Evidence of Life on Mars Should We Risk Going There?

[Nick B]

But thats like saying we cant go anywhere with higher gravity.

 

[BAYLOR]

But thats like saying we cant go anywhere with higher gravity.

Im saying living in lower gravity and environment having families in those places, will have consequences for your descendants. It's something you might want to take into account before you decide to live there.


It's possible we might find earth like planets with gravity levels too great for us to live on. Unless we come up with some kind exo suites .

 

[Mirannan]

One fact that, when found out, will have profound implications is whether Martian life (if any) has the same biochemical basis as that of Earth life. All Earthly life (so far discovered) uses the same DNA base pairs, the same amino acids, the same monosaccharides and the same genetic code for translating one to the other. It is quite conceivable that Martian (or Europan, or Ganymedan, or...) life uses different chemistry; perhaps different DNA bases out of the very large pool of possibilities, or different amino acids ditto, or a different code.

If so, this would mean that ET life had evolved independently of life on Earth and the probability of finding life on extrasolar planets goes way up. If not, it might well mean that all the life in the Solar System evolved in the same place and the chance of finding life on extrasolar planets goes down. Which might in tune mean different decisions about how much effort to put into SETI.

How high, or how low, a gravity level humans can live in indefinitely is a very interesting question about which we have no data. And we won't have any until a few people have babies on the Moon or Mars, in the first case. Nowhere that is otherwise liveable, in the Sol system, has higher gravity than Earth.

 

[Ray McCarthy]

If not, it might well mean that all the life in the Solar System evolved in the same place and the chance of finding life on extrasolar planets goes down.

Or that the Physics, Chemistry, Biology, Maths is such that it's the only way it works. There is actually a high probability that is the case.
There are terrestrial differences in vitamins, amino acids needed by animals and what is poisonous. Also genetic mechanisms re, Sex can be very different. But the fact of the kinds of marsupials in niches elsewhere that are mammals and even look similar is fascinating (What's normally called convergent evolution).

 

[BAYLOR]

Or that the Physics, Chemistry, Biology, Maths is such that it's the only way it works. There is actually a high probability that is the case.
There are terrestrial differences in vitamins, amino acids needed by animals and what is poisonous. Also genetic mechanisms re, Sex can be very different. But the fact of the kinds of marsupials in niches elsewhere that are mammals and even look similar is fascinating (What's normally called convergent evolution).

It seems very unlikely that we are only planet in the whole universe to have given rise to life.

We might even find a world with silicone based life.

 

[Ray McCarthy]

It seems very unlikely that we are only planet in the whole universe to have given rise to life.

I agree, I'll not be surprised if in just our Galaxy, a billion planets have life and 10,000 have intelligent life to the level of some sort of civilisation. I expect too, it will be be similar but different.

We might even find a world with silicone based life.

I'm sure you mean Silicon.
That would be amazing as the chemistry suggests it's impossible.

 

[Karn Maeshalanadae]

Well, who knows?


And yes, I think finding evidence of life should be all the more reason to try to get to Mars. There's no evidence of any current intelligent, sentient life on Mars...but who knows what microbes could show?

 

[Dennis E. Taylor]

I'm sure you mean Silicon.

He may have been thinking of Hollywood.

 

[BAYLOR]

I agree, I'll not be surprised if in just our Galaxy, a billion planets have life and 10,000 have intelligent life to the level of some sort of civilisation. I expect too, it will be be similar but different.


I'm sure you mean Silicon.
That would be amazing as the chemistry suggests it's impossible.

The universe doesn't fall into lock step with how we say it should work . Yes our understanding of science might say that Silicon life is not possible. But we might find that life can arise on worlds that don't follow the same biological and chemical template of our world.

 

[Ray McCarthy]

We have problem if Physics, Chemistry and Maths are not universal.
What makes for enjoyable TV, Film or book may be seriously incompatible with reality, we are reading that script, not writing it.
Biology at higher levels may be unimaginably different. But the chemical properties of Silicon vs Carbon aren't up for debate at all. You can have some synthesized artificial silicon based compounds, but it can't even get in the same league as carbon for organic chemistry, even with laboratory assistance.
Perhaps it's possible, but it's very improbable indeed. Almost everything we know about Physics and Chemistry would have to be a lie.

 

[Mirannan]

I agree, I'll not be surprised if in just our Galaxy, a billion planets have life and 10,000 have intelligent life to the level of some sort of civilisation. I expect too, it will be be similar but different.


I'm sure you mean Silicon.
That would be amazing as the chemistry suggests it's impossible.

He might mean that, but in fact silicone based life may well be more likely. As you say (or imply) silicon chains are very limited in length but silicone chains are unlimited.

As for the business of exotic amino acids being poisonous; well, ET lifeforms might well be poisonous to us, but that doesn't mean life based on them is impossible. Poisons are often poisonous because they are sufficiently similar to various life chemicals to interfere with their metabolism by competing for absorption or binding to enzyme active sites and the like.

And regardless of differences in toxicity, the fact remains that all life forms so far investigated on Earth use the same structural amino acids, the same nucleic acid bases and the same genetic code.

 

[Ray McCarthy]

Silicones are useless as a life building block. They are inert! It's a range of simple Polymers. You might as well postulate life based on Teflon, perspex or Polyurethane.

Silicones are polymers that include any inert, synthetic compound made up of repeating units of siloxane, which is a functional group of two silicon atoms and one oxygen atom frequently combined with carbon and/ or hydrogen. They are typically heat-resistant and rubber-like, and are used in sealants, adhesives, lubricants, medicine, cooking utensils, and thermal and electrical insulation.

https://en.wikipedia.org/wiki/Silicone

I'm not sure that very many useful Silicones are Carbon free either.

the fact remains that all life forms so far investigated on Earth use the same structural amino acids, the same nucleic acid bases and the same genetic code.

In a way it will be surprising if life elsewhere is markedly different at the lower levels of biochemistry.

 

[Mirannan]

Silicones are inert because that's the way humans want them. I can't think of any good reason why more reactive groups couldn't be attached to the backbone instead of the boring stuff we put there. And having life being silicone-based doesn't mean that carbon couldn't also form a part of it. After all, nitrogen and oxygen form part of the chains of the two most common types of structural molecule on Earth - proteins and carbohydrates. (Phosphorus is a major part of the structure of DNA, too.) And sulfur has major use in keeping proteins in shape.

 

[Stephen Palmer]

I think somebody's been watching the 'silicon creature' episode of Star Trek.

 

[BAYLOR]

I think somebody's been watching the 'silicon creature' episode of Star Trek.

There was also an episode of Fantasy Island that had a silicon based monster in it.


But in all seriousness , we don't know what we'll find on other worlds when we get there. We may end up discovering whole new laws of Physics , Biology and Chemistry in other places.

 

[Ray McCarthy]

whole new laws

That's extremely unlikely and would be seriously worrying.

 

[BAYLOR]

That's extremely unlikely and would be seriously worrying.

Finding out that the laws of physics, chemistry and biology have different rules in different places? That would have very frightening implications.

 

[Ray McCarthy]

Piers Anthony (Punishing Magical Land), Bob Shaw (Overland, Ragged Astronauts. pi=3), Terry Brooks (Magic Kingdom?)
Fun in books, I suspect not the case in our universe

 

[BAYLOR]

Piers Anthony (Punishing Magical Land), Bob Shaw (Overland, Ragged Astronauts. pi=3), Terry Brooks (Magic Kingdom?)
Fun in books, I suspect not the case in our universe

Outside the confines of our safe little Earth, we have a very big and very hostile universe. So many things out there could destroy life on Earth.

 

[Ray McCarthy]

The Dinosaurs never saw it coming