Astrophysicists have detected 150 supernovas, a record-breaking number in the Subaru Deep Field -- a full moon sized patch of sky -- which includes 12 of the most ancient and distant ones.
http://ummid.com/news/2011/October/06.10.2011/oldest_supernovas_discovered.htm
http://ummid.com/news/2011/October/06.10.2011/oldest_supernovas_discovered.htm