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View Full Version : Milky Way Harbors “Ticking Time Bombs”



Fraser
2011-Sep-07, 07:00 PM
According to new research, the only thing that may be keeping elderly stars from exploding in their rapid spin. In a galaxy filled with old stars, this means we could literally be sitting on a nearby “time bomb”. Or is this just another scare tactic? (...)Read the rest of Milky Way Harbors “Ticking Time Bombs” [...]

More... (http://www.universetoday.com/88722/milky-way-harbors-ticking-time-bombs/)

trinitree88
2011-Sep-08, 06:07 PM
According to new research, the only thing that may be keeping elderly stars from exploding in their rapid spin. In a galaxy filled with old stars, this means we could literally be sitting on a nearby “time bomb”. Or is this just another scare tactic? (...)Read the rest of Milky Way Harbors “Ticking Time Bombs” [...]

More... (http://www.universetoday.com/88722/milky-way-harbors-ticking-time-bombs/)

Fraser. I won't disagree with the author's premise that there may be lots of ticking bombs out there. But, they won't all be type 1a's. Type 2's also tick merrily along like Captain Hooke's crocodile, and they give a more distinct early warning signal.....iron in the spectra. Type 2's have a short fuse from the day iron begins accumulating in their cores until detonation....typically 2-10 years in the various models. While it was believed decades ago that the mixing in large star's atmospheres would cover up iron in the interiors, that has had some controversial observational refutation in the literature since I came on board AOL's astronomy club and, subsequently, BAUT (2005).
In previous threads I have suggested that an amateur looking for a unique observing program ought to observe a number of asymptotic bue giants periodically to monitor for the appearance of iron, to note the "lighting of the fuse" for a core collapse supernova, and personally gave the talk on "The Late Great Deneb" at Norwich University years ago to stimulate the same thing. i am reminded of the saying " Opportunity does not talk...it whispers.....and says in a very quiet voice, barely discernible...this is an opportunity."
We would likely survive such a spectacular supernova as Deneb, but others would make for great science,too. pete


SEE:http://en.wikipedia.org/wiki/Deneb

SEE:http://en.wikipedia.org/wiki/Monochromator