|
|
The Antennae:
Chandra Locates Mother Lode of Planetary Ore in Colliding Galaxies
This montage of Chandra images shows a pair of interacting galaxies
known as The Antennae. Rich deposits of neon, magnesium, and silicon
were discovered in the interstellar gas of this system.
The top image, a wide field X-ray view, reveals spectacular loops of hot
gas spreading out from the southern part of The Antenna into
intergalactic space. Also shown are huge clouds of multimillion degree
gas and bright point like sources due to neutron stars and black holes.
The image is color coded so that low, medium and high energy X-rays
appear as red, green and blue, respectively.
Direct hits between stars are extremely rare when galaxies collide, but
huge gas clouds can crash into each other at high speeds, creating shock
waves that heat the clouds and the surrounding gas to millions of
degrees. In the closeup view on the lower left, also color coded by
X-ray energies, the point sources have been taken out to emphasize the
hot gas clouds in the central regions of The Antennae.
Collisions between the gas clouds may trigger a stellar baby boom. The
most massive of these young stars race through their evolution in a few
million years and explode as supernovas. Heavy elements manufactured
inside these stars are blown away by the explosions that further heat
the gas clouds and enrich them with heavy elements such as neon,
magnesium, silicon and iron.
The image at the lower right is processed and color-coded to show
regions rich in iron (red), magnesium (green) and silicon (blue). These
are the types of elements that form the ultimate building blocks for
habitable planets.
Enrichment from supernovas occurs in all galaxies, but usually the
new elements are observed in a highly diluted form as they are mixed
up with the rest of the interstellar gas. This Chandra image is remarkable
in that it shows clouds in which magnesium and silicon are 16 and
24 times as abundant as in the Sun.
As the enriched gas cools, a new generation of stars will form, and with
them new planets. A number of studies indicate that clouds enriched in
heavy elements are more likely to form stars with planetary systems.
Several hundred million years from now, an unusually high number of
planets may form in The Antennae.
| Fast Facts for The Antennae:
|
|
Credit
|
NASA/CXC/SAO/G. Fabbiano et
al. |
|
Scale
|
Top: Image is 4.8 arcmin per side; Bottom: Each panel is 2 arcmin per side |
|
Category
|
Normal
Galaxies & Starburst Galaxies |
|
Coordinates
(J2000)
|
RA 12h 01m 53.70s | Dec -18º
52' 35.5" |
|
Constellation
|
Corvus |
|
Observation
Date
|
December 1, 1999; December 29,
2001;
November 22, 2002; May 31, 2002;
April 18, 2002; July 10, 2002; July 13, 2002 |
|
Observation
Time
|
117 hrs |
|
Obs.
ID
|
315, 3040-44, 3718 |
|
Color
Code
|
Energy (Red: 0.3-0.65 keV,
Green: 0.65-1.5 keV, Blue: 1.5-6.0 keV) |
|
Instrument
|
ACIS
|
|
Reference
|
G. Fabbiano et al. 2003, Astrophys. J.
Letters (in press), "X-raying Chemical Evolution
and Galaxy Formation in The Antennae" |
|
Distance Estimate
|
about 60 million light years. |
|
Also Known As
|
NGC 4038/NGC 4039 |
| Release
Date |
January 07, 2004 |
|
|
|
