Massive Star burps, then explodes

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Massive Star burps, then explodes
April 4, 2007 http//spaceflightnow.com/news
Department of Physics National Tsing Hua
University G.T. Chen 2007/5/1
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SN 2006jc

• R.A. 09h 17m 20.78s
• Dec. 41º 54' 32.7"
• Distance 77 M light years in UGC4904
• Constellation Lynx (??)
• Type Ib supernova

Lacks hydrogen and presents non-ionized helium
(He I) line at 587.6 nm and no strong silicon
absorption feature near 615 nm.
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SN 2006jc
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A color image of SN2006jc (center) taken by the
Katzman Automatic Imaging Telescope (KAIT) at
Lick Observatory on Oct. 13, 2006
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Swift Ultraviolet/Optical Telescope image of
Supernova 2006jc in the galaxy UGC 4904 in three
filters
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Swift X-ray Telescope image of Supernova 2006jc
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Chandra X-ray Observatory image of Supernova
2006jc
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SN 2006jc

• On Oct. 20, 2004 , Koichi Itagaki saw the star
  let loose an outburst so bright that it was
  initially mistaken for a supernova.
• On Oct. 11, 2006, astronomers witnessed the star
  actually blowing itself as Supernova 2006jc.

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News

• We have never observed a stellar outburst and
  then later seen the star explode. said Ryan
  Foley.
• Narrow helium spectral lines showed that the
  supernova's blast wave ran into a slow-moving
  shell of material, presumably the progenitor's
  outer layers that were ejected just two years
  earlier.

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News

• Foleys group propose that the star recently
  transitioned from a Luminous Blue Variable (LBV)
  star to a Wolf-Rayet star.
• Similar to the 2004 eruption, LBVs tended to blow
  off large amounts of mass in outbursts so extreme
  that they are frequently mistaken for supernovae.
  
• They called these events are "supernova
  impostors."

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News

• Most astronomers did not expect that a massive
  star would explode so soon after a major
  outburst, or that a Wolf-Rayet star would produce
  such a luminous eruption, so SN 2006jc represents
  a puzzle for theorists.
• It opens up a new window on how some kinds of
  stars die. said Alex Filippenko.

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References

• http//spaceflightnow.com/news
• April 4, 2007
• http//www.nasa.gov/centers/goddard/news/topstory/
  2007/supernova_imposter.html
• ApJ 657L105-L108, 2007 March 10

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gtgtThank youltlt