|
|
NGC 4636:
Hot Galactic Arms Point To Vicious Cycle
Chandra's image of the elliptical
NGC 4636 shows spectacular symmetric arms, or arcs, of
hot gas extending 25,000 light years into a huge cloud
of multimillion-degree-Celsius gas that envelopes the
galaxy. At a temperature of 10 million degrees,
the arms are 30 percent hotter than the surrounding gas
cloud.
The temperature jump, together with the symmetry and
scale of the arms indicate that the arms are the
leading edge of a galaxy-sized shock wave that is
racing outward from the center of the galaxy at 700
kilometers per second. An explosion with an energy
equivalent to several hundred thousand supernovas would
be required to produce this effect.
NGC 4636 with
background subtracted
|
This eruption could be the latest episode in a
feedback cycle of violence that keeps the galaxy in a
state of turmoil. The cycle starts when a hot gas cloud
that envelops the stars in the galaxy cools and falls
inward toward a central, massive black hole. The
feeding of the black hole by the infalling gas leads to
an explosion that heats the hot gaseous envelope, which
then cools over a period of several million years to
begin the cycle anew.
| Fast Facts for NGC 4636: |
| Credit |
NASA/SAO/CXC/C.Jones et al. |
| Scale |
Image is 5 x 4 arcmin |
| Category |
Normal Galaxies & Starburst Galaxies |
| Coordinates (J2000) |
RA 12h 42m 50s | Dec +02° 41' 17" |
| Constellation |
Virgo |
| Observation Dates |
January 26-27, 2000
|
| Observation Time |
15 hours |
| Obs. IDs |
323
|
| Color Code |
Intensity |
| Instrument |
ACIS |
| Distance Estimate |
About 50 million light years |
| Release Date |
December 19, 2001 |
|
|
|
