This morning, I saw an interesting email come into my inbox. It reads as follows:
Subject: [vsnet-alert 16812] Re: PSN J09554214+6940260: bright (11.7 mag) supernova in M82 At UT 2014 Jan 22.305, we obtained a spectrum of PSN_J09554214+6940260 (discoverer: S. J. Fossey) with the Dual Imaging Spectrograph on the ARC 3.5m telescope. We classify this as a Type Ia supernova with a Si II velocity of 20000 km/s. The best superfit match is SN2002bo at -14d. The supernova has a red continuum and deep Na D absorption.
A type 1a supernova is what happens when a binary star system starts to tear itself apart. In essence, a very small dense white dwarf rips the material from the surface of its neighbouring star. It appears to be relatively common when one of the stars in a binary star system inflates when it becomes a red giant. The surface of the red giant is now much closer to the companion star, and so matter starts to transfer from the red giant to the smaller star. As the smaller star accepts matter from the giant, the system becomes unstable, and the small white dwarf explodes violently.
The velocity quoted above shows that the shockwave of this star exploding is travelling at 20,000 km/s - thats almost 12,500 miles per second - pretty quick.
Type 1a supernovae are special because they allow astronomers to accurately gauge the distance from the Earth of the galaxy that spawned it. Each one that is identified gives astronomers much more accurate data about the Universe around us.
I managed to gather a quick snap of Messier 82 tonight before the clouds rolled in. This animation shows the difference between some Messier 82 images I took last year in February versus the 2 exposures I managed to capture tonight.
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