M1: The Incredible
Expanding Crab
From
NASA’s Astronomy
Picture of the Day
The Crab Nebula is
cataloged as M1, the first on Charles Messier's famous
list of things which are not
comets. In fact, the
Crab is now known to be a supernova remnant, an expanding cloud of
debris from the explosion of a massive star.
The violent birth of the
Crab was witnessed
by astronomers in the year 1054. Roughly 10 light-years across today,
the nebula is still expanding at a rate of over 1,000 kilometers per second.
Want to watch the Crab
Nebula expand? Check out this video
(vimeo) animation comparing an image of M1 taken in 1999 at
the European Southern Observatory, with this one,
taken in 2012 at the Mt. Lemmon Sky Center. Background stars were used
to register the two images.
The Crab Nebula lies
about 6,500 light-years away in the constellation Taurus.
Image Credit & Copyright: Adam Block, Mt. Lemmon SkyCenter, U. Arizona
