The High Energy Heart Of The Milky Way
Explanation:
These high resolution false color pictures of the Galactic center
region in high energy
X-ray and gamma-ray light result from a very long
exposure of roughly 3,000 hours performed from 1990 to 1997 by the
French SIGMA telescope onboard the
Russian GRANAT spacecraft.
Each image covers a 14x14 degree field which includes most of the
central bulge of
our Milky Way Galaxy.
The X-ray picture (left) reveals a cluster of sources
releasing enormous amounts of energy.
They are probably
binary star systems where matter accretes
onto a collapsed object, either
a neutron star or
a black hole.
But
according
to recent theories, only those
binary systems with black holes
can radiate above X-ray energies -- in the gamma-ray regime.
In that case, the SIGMA sources also shining in the gamma-ray picture
(right) betray the presence of accreting
stellar black holes!
Surprisingly, no high energy source seems to coincide exactly
with the Galactic center itself,
located near the brightest source at the bottom of both
pictures.
This indicates that
the
large black hole
thought
to be lurking there
is unexpectedly quiet at these energies.
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.
