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Dusty old star offers window to our future --- GD 362 Department of Physics National Tsing Hua University G.T. Chen 2005/10/20 GD 362 White Dwarf star R.A. 17h 31m 34.33s Dec. +37° 05' 20.6" Distance: 22~26 pc It represents the end state of stellar evolution of stars like the Sun Its progenitor had an original mass about seven times the Sun’s From the death of GD362,it passed two to five billion years based on the cooling rate This long time frame would explain why there is no sign of planetary nebula from the exclusion of material as the star died This star is as rich calcium, magnesium and iron elements as the Sun’s From the observation, there is a dust disk around the white dwarf Why the disk can survive ? something similar to the asteroid or possibly even a planet around the star is being ground up and broken to feed the star with dust In the future , our solar system may have the same conditions like this case GD 362 Reference http://spaceflightnow.com/news/ GEMINI OBSERVATORY NEWS RELEASE Posted: September 26, 2005 http://www.gemini.edu/home.php ApJ 632,119-122 , 2005 A dusty disk around GD 362, a white dwarf with uniquely high photospheric metal abundance >>Thank You<<