Posted on 06/10/2009 9:14:37 PM PDT by TaraP
Where did you get that information? Any idea what the time lag would be between the arrival of light and the arrival of debris? I’m wondering what our window is to set up defensive measures.
Depends on what percentage of the speed of light the particles travel, and if there are any dust clouds or other obstacles to particle travel between us and the “big beam gun.”
Also depends on if the rotation axis is pointing at us or not.
Most of the data I got from Wikisky.org. (A must see 3D mapping site.)
As to the debris, it will be a while before even the fastest of it reaches us. Picture a spherical dispersion pattern across 640LY of dust and stellar filled space.
There will be NO large pieces of “debris”. The “nebula” which forms from a supernova explosion consists of gas, not solid matter.
This article does the best job of describing the process to those at least somewhat technically minded that I’ve seen:
http://cass.ucsd.edu/public/tutorial/SN.html
So the answer to “how long” before the supernova is highly dependent on which “shell of fusion” is now being exhausted. Taking these numbers as exactly accurate, if it is exhausting the “helium burning” phase, the Betelgeuse will expand again and be in the Carbon burning phase for another 300 years. On the other hand if it is going into the Oxygen burning phase, the core collapse is imminent. Note that the core collapses independently of the external “surface” and MUCH more rapidly, in fact “catastrophically”. (I’ve seen estimates near 70,000km/sec.) [Of course, it is possible that that this is merely a size oscillation which is not understood or covered by current theory.]
The distance believed to be “safe distance” from a supernova of this type is about 300 light years, and if so, we’ll be OK here, provided the star’s pole is NOT pointed “at us”. It is estimated that there is only about one supernova in the Milky Way Galaxy per century. If Betelgeuse DOES go soon, it will be a remarkably close- Ring Side seats!
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