[jleahy]

You are talking about chirality. Biologically produced molecules are all of the same "handedness", but molecules produced by other means (normal chemical reactions) tend to have 50/50 chance to be either handedness (although selective reactions are possible).

So you'd expect to see both at a 50/50 ratio in a meteorite, if you see any at all. That's just chemistry.

[throwGuardian]

Why 50/50? It should take on the statistics of causations of chirality. And based on that, one might be able to guess the exact location and orientation of the meteorite when these chemicals were formed