[tomohelix]

One way to interpret the results here is that all the building blocks of life can naturally be formed right here on earth or anywhere that has conditions similar to where Bennu came from.

The fact that the components on the asteroid is racemic meant or heavily suggested that they were formed using non-biogenic means. And if so, it also means that Earth could have had the same thing happened a long time ago, leading to the seeds of life.

tl,dr: this discovery weaken the panspermia hypothesis.

[kjkjadksj]

I don’t see how it weakens the hypothesis. We are making the assumption that life must be chiral. Maybe chirality is something more or less inherited. So it is a coin flip whether your last ancestor was left handed or right handed. So a racemic mix doesn’t disprove that because the population could be heterogeneous for this phenotype and not yet fixed. There are many heterogeneous phenotypes on earth.

[scotty79]

It seems unlikely for such a hard thing as spontaneous creation of biomachinery from amino-acids happened at the same time for both left-handed and right-handed versions. And once you got machinery that uses, for example, left-handed version, it's pretty much game over for the alternative because life grows, evolves and colonizes at insane rates compared to random chemical processes. So it's very likely that wherever carbon based life exists it's chiral rather than racemic.

[ajuc]

If life is chiral it weakens the hypothesis. If life is not chiral it changes nothing.

Nonzero-weighted sum of something and nothing is something.