Messier object 82 or M82 is a spiral galaxy about 11.5 million light years away from us. If you do the math (a light year is approximately 6 trillion miles) it's pretty far away but as galaxies go, it's a veritable neighbor to our Milky Way. For amateur astronomers, it's an easy target and at our Oregon Observatory at Sunriver, it's a popular object which we look at frequently along with its companion, M81.
This month, it was discovered that a star went super nova in M82. A super nova is a star that violently explodes in its death throes. For a short while, the super nova can outshine even the entire galaxy it dwells in and radiates more energy than our Sun will in its entire lifetime.
Named SN (super nova) 2014J, it has been designated as a Type Ia super nova (an exploded white dwarf) with debris that is moving away from the site of the explosion at up to 20,000 miles per second! Prior to going nova, this star was likely about the size of the earth but because of its super density, it had the gravitational power of a sun-sized star. White dwarf stars that super nova are generally thought to be a part of a binary star system. The white dwarf pulls hydrogen gas from its companion. That gas settles on the surface of the white dwarf and compresses it even more. When the star packs on enough mass to be the equivalent of about 1.4 times our star's mass, it can no longer support itself, collapses, heats up to incredibly high temperatures and then explosively burns up in a cataclysmic and runaway fusion reaction.
According to spectral analysis, by Yi Cao and associates at CalTech, on January 22, SN2014J is still about two weeks from its brightest. At the moment, the super nova has been measured at approximately 10.4 magnitude, too dim to see with the naked eye but in reach of most back yard telescopes. There is definitely a possibility that it will become bright enough to see with a common binocular.
Now is the time to view this incredible event and viewing it is most dramatic if viewed on subsequent nights so that the actual brightening of the super nova is apparent. The moon will cooperate until about February 2nd or 3rd.
M82 is relatively easy to find. Using the star map below, locate the two stars in the Big Dipper Phecda and Dubhe, two of the bowl stars. M82 is about 1 degree off the line that you would follow using those two stars. In a binocular, you'll likely see the two smudges formed by M81/M82 at the corner of your field of view. The second map below gives a more detailed "star hopping" route to the two galaxies.
Just a note for non-seasoned stargazers. The images here are photographic images. The pair of black and white images above are not quite what you will see through a telescope unless you have very clear and steady skies and high magnification. The first image was taken by the Hubble telescope and one we will never see using any sort of amateur telescope (or professional one for that matter) Cameras are far more sensitive to colors than our eyes are.
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