Galaxy Clusters and Dark Energy:
Astronomers Take the Measure of Dark Matter in universe
Credit: X-ray: NASA/IOTA/S.Allen et al. Optical: HST
This montage shows two sets of
Chandra X-ray Observatory images (left) and Hubble
Space Telescope images (right) of the giant galaxy
clusters Abell 2390 and MS2137.3-2353. The
clusters are located 2.5 and 3.1billion light years
from Earth respectively. The X-ray emission comes from
the multimillion-degree gas that fills the clusters.
Chandra provides detailed temperature maps for this gas
and allows astronomers to precisely determine the
masses of the clusters. Most of the mass is in the form
of dark matter.
The Hubble Space Telescope optical images show the
distribution of galaxies in the central regions of the
clusters. The gravity of the dark matter associated
with the brightest galaxies in the clusters and the
cluster as a whole bends light from distant background
galaxies to produce the giant arcs seen in the images.
The Hubble Space Telescope data place independent
constraints on the masses of the clusters that confirm
the Chandra results.
Fast Facts for Abell 2390: |
Credit |
X-ray: NASA/IOTA/S.Allen et al. Optical: HST |
Scale |
12 x 9 arcmin across. |
Category |
Groups & Clusters of Galaxies |
Coordinates (J2000) |
RA 21h 53m 36.50s | Dec +26° 35' 27" |
Constellation |
Pegasus
|
Observation Dates |
Nov 7, 1999 |
Observation Time |
3 hours |
Distance Estimate |
2.7 billion light years
|
Release Date |
September 06, 2001 |
|
Fast Facts for MS 2137.3-2353: |
Credit |
X-ray: NASA/IOTA/S.Allen et al. Optical: HST |
Scale |
4 x 3 arcmin across. |
Category |
Groups & Clusters of Galaxies |
Coordinates (J2000) |
RA 21h 40m 12.70s | Dec -23° 39' 27.00" |
Constellation |
Capricornus
|
Observation Dates |
Nov 18, 1999 |
Observation Time |
6 hours |
Distance Estimate |
3.5 billion light years
|
Release Date |
September 06, 2001 |
|