Chandra looks at the aftermath of a massive star explosion
NASA’s Chandra X-ray Observatory has captured a spectacular
image of G292.0+1.8, a young, oxygen-rich supernova remnant with a
pulsar at its center surrounded by outflowing material. Astronomers
know that pulsars are formed in supernova explosions, but they are
currently unable to identify what types of massive stars must die in
order for a pulsar to be born. Now that Chandra has revealed strong
evidence for a pulsar in G292.0+1.8, astronomers can use the pattern
of elements seen in the remnant to make a much closer connection
between pulsars and the massive stars from which they form.
This Chandra image shows a rapidly expanding shell of gas that is 36
light years across and contains large amounts of elements such as
oxygen, neon, magnesium, silicon and sulfur. Embedded in this cloud
of multimillion degree gas is a key piece of evidence linking neutron
stars and supernovae produced by the collapse of massive stars.
Standing out at higher X-ray energies, astronomers found a point-like
source surrounded by features strikingly similar to those found around
the Crab Nebula and Vela pulsars. These features, together with the
X-ray spectrum of the central source and surrounding nebula, provide
strong evidence that a rapidly spinning neutron star is responsible
for the central observed X-radiation.
Astronomers believe that an oxygen-rich supernova explosion is
triggered by the collapse of the core of a massive star to form a
neutron star, releasing tremendous amounts of energy in the process.
“This finding is very important, since it would allow us to
conclusively associate this young, oxygen-rich supernova remnant with
a core collapse, massive star supernova explosion” said John P.
Hughes of Rutgers University, lead author of a paper describing the
research which appeared in the October 1, 2001, issue of The
Astrophysical Journal.
With an age estimated at 1,600 years, G292.0+1.8 is one of three known
oxygen-rich supernovae in our galaxy. These supernovae are of great
interest to astronomers because they are one of the primary sources of
the heavy elements necessary to form planets and people.
Scattered throughout the image are bluish knots of emission containing
material that is highly enriched in newly created oxygen, neon, and
magnesium produced deep within the original star and ejected by the
supernova explosion. Elsewhere in the image one can trace whitish
colored regions (like the thin, nearly horizontal filaments just above
the purple nebula) and yellow regions (mainly around the periphery,
best seen toward the upper right). This material is of a more
standard composition without the enrichment seen elsewhere and
represents either the pre-existing surrounding matter or the outer
layers of the star itself, lost at an earlier time before the star
exploded as a supernova.
The research team, which also included Patrick Slane (Smithsonian
Astrophysical Observatory), David Burrows, Gordon Garmire, and John
Nousek (Penn State University), Charles Olbert and Jonathan Keohane
(North Carolina School of Science and Mathematics), used the Advanced
CCD Imaging Spectrometer instrument to observe G292.0+1.8 on March 11,
2000.
ACIS was conceived and developed for NASA by Penn State and MIT under
Garmire’s leadership. NASA’s Marshall Space Flight Center in
Huntsville, Ala., manages the Chandra program. TRW, Inc., in Redondo
Beach, Calif., is the prime contractor for the spacecraft. The
Smithsonian’s Chandra X-ray Center controls science and flight
operations from Cambridge, Mass.
Images associated with this release are available on the World Wide
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