Cosmic Rays and Supernova Dust
Credit & Copyright: M. DeBord, R. Ramaty and B. Kozlovsky
(GSFC),
R. Lingenfelter (UCSD),
NASA
Explanation:
Cosmic Rays
are celestial high energy particles traveling
at nearly the speed of light, which constantly bombard the Earth.
Discovered during
high altitude balloon flights in 1912
their source has been a long standing mystery.
But a recent theory suggests that
cosmic ray particles are
atomic nuclei blasted from dust grains
formed in supernovae, the death explosions of massive stars.
This artist's illustration shows a supernova explosion
(at left) and a conical
section of the expanding cloud
of ejected material.
Atoms are torn from the brownish bands of
"dust"
material by shock waves (represented by orange rings).
The shocks in the expanding blast wave
then accelerate the atoms
to near light speeds firing them into interstellar space like
cosmic bullets.
The theory is supported by observations indicating
that high velocity dust was formed in
the nearby supernova 1987A,
and that Beryllium, a light element created in
Cosmic Ray collisions, is found equally in both old an young stars.
NASA's
Advanced Composition Explorer (ACE) satellite can also test details of
the theory by directly measuring Cosmic Rays.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
