Distant Stellar Explosion Helps Map Universe's Dark Ages 61
sciencehabit (1205606) writes "Near the beginning, the universe was without form and void, and darkness was upon the face of the deep. That's because until about a billion years after the big bang, there were no galaxies or stars to illuminate the heavens, which were then filled primarily with neutral hydrogen gas. But a rare ultra–high-energy stellar explosion called a gamma ray burst has offered a new glimpse into this obscure period—the so-called cosmic dark ages—and may help nail down precisely when it ended. A new study of the explosion's afterglow suggests that such neutral hydrogen abounded a billion years after the big bang, so the dark ages weren't quite over then."
Re:I don't understand something (Score:4, Informative)
why can we detect objects that are as far as 13.3 billion light years away?
"...years ago", rather than "light years away," really. The light has taken 13.3 billion light years to get here, but the source was closer than 13.3 billion light years away when the light was emitted, and is further than 13.3 billion lights years now* (by about 3-4 times).
*for a certain value of "now"