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.
February 7, 1997
Explanation: The Crab Nebula is filled with mysterious
filaments. The Crab Nebula
is the result of a star that exploded in 1054 AD.
This spectacular supernova
explosion was recorded by Chinese
and (quite probably) Anasazi Indian
astronomers. The filaments are mysterious because they appear
to have less mass than expelled in the original supernova
and higher speed than expected from a free explosion.
In the above picture,
the colour indicates what is happening to the electrons in different
parts of the Crab Nebula.
Red indicates the electrons are recombining with protons to form neutral hydrogen,
while green indicates the electrons are whirling around the magnetic field
of the inner nebula. In the nebula's
very centre lies a pulsar:
a neutron star
rotating, in this case, 30 times a second.
Authors & editors:
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.