Composite image of the spiral galaxy NGC 3079: Superwind
sculpts filamentary features
[http://www1.msfc.nasa.gov/NEWSROOM/news/photos/2003/photos03-030.html]
A Chandra X-ray Observatory image, in blue, has been
combined with Hubble’s optical image, in red and green,
to compose this stunning and revealing picture of the
spiral galaxy NGC 3079. Towering filaments consisting
of warm (about ten thousand degrees Celsius) and hot
(about ten million degrees Celsius) gas blend to create
the bright horseshoe-shaped feature near the center.
The correlation of the warm and hot filaments suggests
that they were both formed as a superwind of gas —
rushing out from the central regions of the galaxy —
carved a cavity in the cool gas of the galactic disk.
The superwind stripped fragments of gas off the walls
of the cavity, stretched them into long filaments, and
heated them. The full extent of the superwind shows up
as a fainter conical cloud of X-ray emission surrounding
the filaments.
A superwind, such as the one in NGC 3079, originates in
the center of the galaxy either from activity generated
by a central supermassive black hole or by a burst of
supernova activity. Superwinds are thought to play a
key role in the evolution of galaxies by regulating the
formation of new stars, and by dispersing heavy elements
to the outer parts of the galaxy and beyond. These
latest Chandra data indicate that astronomers may be
seriously underestimating the mass lost in superwinds
and, therefore, their influence within and around the
host galaxy.
NASA’s Marshall Space Flight Center in Huntsville, Ala.,
manages the Chandra program for NASA. (NASA/CXC /U.
North Carolina/G. Cecil)
