Astronomers have
detected X-rays from the leftovers of a supernova that was first seen from
Earth over 50 years ago. This supernova SN 1957D was call because it was the
fourth one detected in the year 1957. Whilst detected in the radio and optical
for decades, SN 1957D did not appear in previous X-ray images.
Astronomers
needed a long observation (8.5 days) from Chandra of the spiral galaxy where SN
1957D is finally found to detect it. The Chandra data suggest a rapidly revolving
neutron star was formed by the explosion, which would be one of the youngest
objects of this type ever observed.
Over fifty years
ago, a supernova was discovered in M83, a spiral galaxy 15 million light years
acerca from Earth. Astronomers have used NASA's Chandra X-ray Observatory to
make the first detection of X-rays emitted by the debris from this explosion.
SN 1957D Named
Because It was the fourth supernova to be discovered in the year of 1957, it is
one of only a few located outside of the Milky Way galaxy is detectable That,
in Both Radio and optical wavelengths, Decades after its blast was observed. In
1981, astronomers saw the remnant of the exploded star in radio waves, and then
in 1987 they detected at optical wavelengths the remnant, years after the light
from the blast itself became undetectable.
A relatively
short observation - about 14 hours long - from NASA's Chandra X-ray Observatory
in 2000 and 2001 did not detect any X-rays from the remnant of SN 1957D.
However, a much longer observation Obtained in 2010 and 2011, totaling nearly 8
and 1/2 days of Chandra time, did reveal the Presence of X-ray emission. The
X-ray brightness in 2000 and 2001 was about the same as or lower than In This
deep image.
This new Chandra
image of M83 is one of the deepest X-ray observations ever made of a spiral
galaxy beyond our own. This full-field view of the spiral galaxy shows the low,
medium, and high-energy X-rays Observed by Chandra in red, green, and blue respectively.
The location of SN 1957D, Which is found on the inner edge of the spiral arm
just above the galaxy's center, is outlined in the box (or can be seen by mussing
over the image.)
The new X-ray
data from the remnant of SN 1957D Provide important information about the
nature of this explosion, astronomers think that Happened When a massive star
ran out of fuel and collapsed. The distribution of X-rays with energy Suggests
That SN 1957D contains a neutron star, a rapidly spinning, dense star Formed When
the core of pre-supernova star collapsed. This neutron star, or pulsar, may be
producing a cocoon of charged particles moving at close to the speed of light
press Known as wind nebula.
If this
interpretation is confirmed, the press in SN 1957D is observed at an age of 55
years, one of the youngest pulsars ever seen. The remnant of SN 1979C in the
galaxy M100 contains another candidate for the youngest pulsar, but astronomers
are still unsure Whether there is a black hole or press at the center of SN 1979C.
An image from
the Hubble Space Telescope (in the box labeled “Optical Close-Up ") that
shows the debris of the blast that created SN 1957D is located at the edge of a
star cluster less than 10 million years old. Many of These Stars Are estimated to
have about 17 times those masses of the Sun. This is just the right mass for a
star's evolution to result in a core-collapse supernova as is thought to be the
case in SN 1957D.
These results
will appear in an upcoming issue of The Astrophysical Journal. The Researchers
Involved with This study Were Knox Long (Space Telescope Science Institute),
William Blair (Johns Hopkins University), Leith Godfrey (Curtin University,
Australia), Kip Kuntz (Johns Hopkins), Paul Plucinsky (Harvard-Smithsonian Center
for Astrophysics) Roberto Soria (Curtin University), Christopher Stockdale
(University of Oklahoma and the Australian Astronomical Observatory), Bradley
Whitmore (Space Telescope Science Institute), and Frank Winkler (Middlebury
College).
NASA's Marshall
Space Flight Center in Huntsville, Ala., Manages the Chandra program for NASA's
Science Mission Directorate in Washington. The Smithsonian Astrophysical
Observatory controls Chandra's science and flight operations from Cambridge,
Mass.
Fast Facts for SN
1957D in M83:
Credit X-ray: NASA / CXC / STScI / K.Long et al.,
Optical: NASA / STScI
Release Date July 30, 2012
Scale 9.5 arcmin on a side (~ 41.000 light
years); Inset image: 1.6 x 1.3 arcsec (~ 120 x ~ 100 light years)
Category Normal Galaxies & Starburst
Galaxies
Coordinates
(J2000) RA 13h 37m 00.80s | Dec -29
51 58.60
Constellation Hydra
Observation Date 12 pointings Between April 29, 2000
and Dec 28, 2011
Observation Time 219 hours 49 min.
Obs. ID 793, 2064, 12420, 12992-12996,
13202, 13241, 13248, 14332, 14342
Instrument ACIS
Also known as NGC 5236
References Long, K. et al, 2012, (in press) arXiv:
1207.1555
Color Code X-ray: (Red, Green, Blue); Optical inset
(Red, Green, Blue)
Distance
Estimate 15 million light years
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