This article from 2014 is fascinating: electrons with a preferred left-handed spin might be more likely to destroy right-handed organic molecules, and that could possibly explain why all Earthly life forms use left-handed amino acids. (note the weasel words “might”, “possibly”, etc).
I found this link in an also-interesting article shared by Ciro Villa about artificially creating right-handed DNA: http://www.nature.com/news/mirror-image-enzyme-copies-looking-glass-dna-1.19918
http://www.nature.com/news/force-of-nature-gave-life-its-asymmetry-1.15995
So asteroids and comets contains dna’s life in sideral space. It runs around and falls over planets in several solar systems.
That’s great!
Cometas e asteroides contém dna da vida inteligente vagando pelo espaço cósmico e povoando mundos.