Discover the cosmos! Each day a different image or photograph of
our fascinating universe is featured, along with a brief
explanation written by a professional astronomer. October 16,
1996 Explanation: Research balloon flights conducted in 1912 by
Austrian physicist Victor Hess revealed that the Earth was
constantly bombarded by high energy radiation from space - which
came to be called "Cosmic Rays". What are Cosmic Rays and where
do they come from? They are now known to be mostly subatomic
particles - predominantly protons and electrons - but their
origin is a long standing mystery. After almost a century of
study, this cosmic puzzle may have been at least partially
solved by new X-ray images and spectra from the ASCA satellite
observatory. Pieced together to show the region around a star
observed to go supernova in 1006 AD, the overlapping X-ray
snapshots above (seen in false color) reveal the bright rims of
the exploded star's still expanding blast wave. These ASCA
observations show for the first time tha