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

2. SN 2006jc ► R.A. : 09h 17m 20.78s ► Dec. : +41 º 54' 32.7" ► Distance: ~77 M light years in UGC4904 ► Constellation: Lynx ( 山貓 ) ► 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.

3. SN 2006jc

4. A color image of SN2006jc (center) taken by the Katzman Automatic Imaging Telescope (KAIT) at Lick Observatory on Oct. 13, 2006

5. Swift Ultraviolet/Optical Telescope image of Supernova 2006jc in the galaxy UGC 4904 in three filters

6. Swift X-ray Telescope image of Supernova 2006jc

7. Chandra X-ray Observatory image of Supernova 2006jc

8. 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.

9. 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.

11. News ► Foley ’ s 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."

13. 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.

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

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