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NGC 6543 (Cat's Eye Nebula):
Chandra Reveals The X-Ray Glint In The Cat's Eye
Left image: The X-ray data from the Chandra X-ray Observatory have revealed a bright central star surrounded by a cloud of multimillion-degree gas in the planetary nebula known as the Cat's Eye. This Chandra
image, where the intensity of the X-ray emission is
correlated to the brightness of the orange coloring,
captures the expulsion of material from a star that is
expected to collapse into a white dwarf in a few
million years. The intensity of X-rays from the central
star was unexpected, and it is the first time
astronomers have seen such X-ray emission from the
central star of a planetary nebula. The ACIS X-ray
camera aboard Chandra observed NGC 6543 on May 10-11,
1999, for a total exposure time of 46,000
seconds.
Right image: This composite image of Chandra and
Hubble Space Telescope data offers astronomers an
opportunity to compare where the hotter, X-ray emitting
gas appears in relation to the cooler material seen in
optical wavelengths. The Chandra team found that the
chemical abundances in the region of hot gas (its X-ray
intensity is shown in purple) were like those in the
wind from the central star and different from the outer
cooler material (the red and green structures.)
Although still incredibly energetic and hot enough to
radiate X-rays, Chandra shows the hot gas to be
somewhat cooler than scientists would have expected for
such a system. These results present a puzzle since the
temperature of the X-ray emitting material suggests
that mixing might have occurred. This discrepancy means
some other process has created the "lukewarm" X-ray
emission observed by Chandra. The color composite of
optical and X-ray images was made by Zoltan G. Levay
(Space Telescope Science Institute). The optical images
were taken by J.P. Harrington and K.J. Borkowski
(University of Maryland) with the Hubble Space
Telescope.
| Fast Facts for NGC 6543: |
| Credit |
Left: X-ray (NASA/UIUC/Y.Chu et al.), Right: X-ray/Optical Composite (X-ray: NASA/UIUC/Y.Chu et al., Optical: NASA/HST) |
| Scale |
Images are 30 arcsec on a side. |
| Category |
White Dwarfs & Planetary Nebulas |
| Coordinates (J2000) |
RA 17h 58m 33.30s | Dec +66'° 37' 59.20" |
| Constellation |
Draco |
| Observation Dates |
May 10-11, 2000
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| Observation Time |
13 hours |
| Obs. IDs |
630
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| Color Code |
Intensity |
| Instrument |
ACIS |
| Distance Estimate |
About 3,000 light years |
| Release Date |
January 08, 2001 |
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