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NGC 1569:
Dwarf Galaxy Gives universe A Breath of Fresh Oxygen
The Chandra image of NGC 1569, a dwarf galaxy 7
million light years from Earth, shows large hot
bubbles, or lobes extending above and below a disk of
gas along the equator of the galaxy. The 27-hour
observation allowed scientists to measure for the first
time the concentration of oxygen, neon, magnesium, and
silicon in the bubbles and the disk. They found that
bubbles contain oxygen equal to the oxygen contained in
3 million suns.
For the last 10 million to 20 million years NGC 1569
has been undergoing a burst of star formation and
supernova explosions, perhaps triggered by a collision
with a massive gas cloud. The supernovas eject oxygen
and other heavy elements at high velocity into the gas
in the galaxy, heating it to millions of degrees. Hot
gas boils off the gaseous disk of the galaxy to form
the bubbles, which expand out of the galaxy at speeds
of hundreds of thousands of miles per hour.
This illustration
depicts the orientation of NGC 1569 and the
line of sight from which Chandra observed
it.
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Dwarf galaxies are much smaller than ordinary galaxies
like our Milky Way. Because of their size, they have
relatively low gravity and matter can escape from them
more easily. This property, combined with the fact that
dwarf galaxies are the most common type of galaxy in
the universe, makes them very important in
understanding how the universe was seeded with various
elements billions of years ago, when galaxies were
forming.
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Fast Facts for NGC
1569:
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Credit
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NASA/CXC/UCSB/C.Martin et al.
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Scale
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Image is 5.2 arcmin on a side.
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Category
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Normal
Galaxies & Starburst Galaxies |
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Coordinates
(J2000)
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RA 04h 30m 49s | Dec +64º 50'
54" |
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Constellation
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Camelopardus
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Observation
Date
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April 11, 2000
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Observation
Time
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27 hours
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Obs.
ID
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782
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Color
Code
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Energy
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Instrument
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ACIS
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Distance
Estimate
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about 7 million light years
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Release Date
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July 23, 2002
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