Galaxy Cluster A2199
Explanation:
It's bigger than a bread box. In fact, it's
much bigger than all bread boxes put together.
Abell 2199
is huge. In fact, it is a close, large cluster
of galaxies,
containing several
thousands
of galaxies
centered around a central dominant galaxy. "Close,"
however, is only relative to other
clusters of galaxies,
since light takes about 50 million years to reach us from
A2199. All of the fuzzy objects in the above picture are
galaxies,
but these galaxies do
not contain most of the matter in
the cluster. By studying clusters like A2199, astronomers conclude
that some form of
dark matter
dominates the motion of the bright galaxies. What, exactly, this
dark matter
is poses one of the greatest astronomical puzzles of modern times.
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.
