Adjective
protostellar (not comparable)
(astronomy) Of or pertaining to a protostar.
The molecule was found around the protostellar binary IRAS 16293-2422, which is located 400 light years from Earth. citation citation Glycolaldehyde is needed to form ribonucleic acid, or RNA, which is similar in function to DNA. Source: Internet
Therefore, in today's photosphere the helium fraction is reduced, and the metallicity is only 84% of what it was in the protostellar phase (before nuclear fusion in the core started). Source: Internet