Finally got a chance to see the exploding comet C/2012 X1 (LINEAR) from my home this morning through a 10-inch telescope. You’ll recall this is the comet that went from 14th magnitude obscurity straight to binocular brightness without passing Go. The comet’s located in the dim constellation Coma Berenices not far from the handle of the Big Dipper. To see it you have to get up about two hours before sunrise and have a clear view of the northeastern sky. Even at start of dawn, X1 is only about 15 degrees or a “fist and a half” above the horizon.
I was excited by what I saw. Italian amateur astronomer Gianluca Masi’s photo captures its low-power telescopic appearance well. To my eye the comet was a bright, dense, hazy ball of magnitude 7.5 with a compact knot of brighter material at its center. I could kick myself for forgetting to check it out in binoculars – even in last quarter moonlight I suspect the comet was bright enough to spot in 50mm and larger glasses.
Now the wait is on. Once the moon gets whittled down to a crescent and becomes less of a glare bomb, we’ll soon see how well it may show in small telescopes. I encourage you to watch how the comet evolves in the coming weeks. It’s already brighter than when first seen in outburst on Oct. 21 and continues to expand. I estimated its size at 4-5 arc minutes or about 1/6 the size of the full moon. It’s amazing to see a comet this bright at the remote distance of 279 million miles.
Don’t you love it? With all eyes focused on Comet ISON, here comes this upstart from deep space wanting to share a bit of the limelight. While it’s possible the comet was struck by a meteoroid, exposing fresh ices to fizz and broil in sunlight, a more likely cause for the outburst is heated gas beneath the surface breaking through and exposing fresh ice. Solar heating converts the ice directly to gas in a process called sublimation forming a tenuous glowing globe around the comet’s nucleus called a coma.
Watch this blog for more updates and finder maps for the comet in the coming weeks.