All 5 units of life's genetic code were just discovered in an asteroid sample
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2 hours ago
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the_real_cher
2 hours ago
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How legit is this?

This seems like insanely huge news?

It implies life was seeded on earth and not generated via abiogenesis.

And therefore exists elsewhere in the universe, or did at one point.

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tsoukase
5 minutes ago
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It is indeed big news IF the sample is not polluted from the ample existence of nucleotides in earth. Using the Bayes theorem the possibility of seeded life from the universe is not negligible any more. But the geological time scales bring us not far more.
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ksymph
2 hours ago
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We didn't find evidence of life on the asteroid; rather, we found the necessary building blocks for it, which, in the right environment (e.g. earth), could become life.

If anything it slightly moves the scales toward abiogenesis, since it implies the necessary precursors to life were common in the early solar system, though it's certainly not conclusive either way.

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JumpCrisscross
24 minutes ago
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> moves the scales toward abiogenesis

Or the warm early universe hypothesis. In its early life, the entire universe was at a temperature that could sustain liquid water literally anywhere. The idea being, in this hypothesis, life was literally everywhere and then went dormant.

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nzach
2 hours ago
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> It implies life was seeded on earth and not generated via abiogenesis.

I don't think this conclusion is correct. The abiogenesis/panspermia debate is about where life formed. This article only says "we found all the DNA/RNA bases in an asteroid," but there is a HUGE gap between DNA bases and life(ie self-replicating organisms).

Making a crude analogy you could say they found Lego pieces in the asteroid, but that doesn't imply that the first 'Lego kits' on earth came pre-assembled. They might, or might not. We don't really have enough information to get a definitive conclusion. What we know is that we can't discard the panspermia idea yet.

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octopoc
1 hour ago
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But doesn’t that mean that there must be life elsewhere? I.e. those Lego blocks must have come from a complete set somewhere else, right?
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nzach
1 hour ago
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No, not really.

Let me put it in another way, imagine we find clay in an asteroid. Does that alone imply the existence of ceramic in other places of the universe?

We need these molecules to build build a DNA strand, but their existence doesn't imply the existence of other life forms. Maybe exists a process that produce these molecules naturally and we just don't know about yet.

And remember that life(self replicating organisms) is way more complex than just DNA/RNA. In another crude analogy you could say that DNA is just the source code, to have life you still need to have all the hardware to run this code on. (fun fact: that is the reason why people argue about virus being something alive or not. Generally it has only the RNA necessary for the replication, and this is why it can only reproduce if it is able to take over another cell. In this analogy it has the source code but not the hardware, so how do we classify it?)

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BetaDeltaAlpha
1 hour ago
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If genetic bases can be created by abiogenesis on earth, they can be created by abiogenesis elsewhere in space.
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karmakaze
1 hour ago
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All through history groups of people thought they were the population and surprised each time to find others in other parts of the land, other islands, other continents. At some point you recognize the pattern and think Earth could just be another more distantly separated island. The difference would be that the next other people may be almost inconceivably different than us.
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PaulHoule
2 hours ago
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Similar molecules have been found in meteors for a long time so it is not a surprise. There is no proof life started off planet but it is also possible.
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