Distant Supernova, Dark Energy.

A pinpoint of light from a star that exploded over 10 billion light-years away is centered in the panel at the lower right, a cosmic snapshot of the most distant supernova . The ancient stellar detonation was detected by digitally subtracting before and after images of a faint, yellowish, elliptical galaxy included in the Hubble Space Telescope Deep Field image illustrated at the top and left. Remarkable in itself as the farthest known supernova , its measured brightness provides astounding evidence for a strange universe - one which eventually defies gravity and expands at an accelerating rate. The unseen force driving this expansion is attributed to “ dark energy ” and discovering the fundamental nature of dark energy has been called the challenge of this millennium.