10:00 AM | Comet Lovejoy rings in the New Year!

[Image of Comet Lovejoy on 12/29/14; courtesy "spaceweather.com"]

Discussion

Comet Lovejoy is just now becoming visible to the naked eye in the northern hemisphere and it is expected to more than double in brightness by mid-January. Currently, the comet shines at magnitude +5.0 and can be seen in dark sky conditions as a fuzzy patch near Orion’s belt several hours after sunset. This is the fifth comet discovered by the Australian astronomer Terry Lovejoy – officially named C/2014 Q2 - and it will pass about 70 million kilometers (44 million miles) from the Earth on January 7th with its peak brightness expected to reach around 4th magnitude which should be pretty easily visible without any optical aid. The location of Comet Lovejoy will be a bonus as it should be relatively easy to find near the constellation of Orion. It’ll also glide past Taurus and the Pleiades over the next few weeks. The comet is moving to the north so it is getting higher all the time for Northern Hemisphere observers.

By January 7th – the time of closest approach – the nearly full moon will make it tougher to see, but after that the moon will rise late enough that it won’t be as big of a problem. In the photo (above) the comet-head appears green and the tail appears blue; however, those colors will likely not be apparent to the naked eye. These colors come from ionized carbon monoxide (CO+) and diatomic carbon (C2), which glow blue and green, respectively, in the near-vacuum of interplanetary space. Long exposure photography tends to bring out the green hue in the comet-head. As for the physical nature of the comet itself, it’s on a pretty long-period orbit, taking about 14,000 years to go around the Sun. The orbit takes it out to a distance of nearly 90 billion kilometers (for comparison, Neptune orbits at a distance of 4.5 billion kilometers).

Finder charts for January can be found here courtesy "Sky and Telescope": http://www.skyandtelescope.com/wp-content/uploads/Lovejoy2_BW.pdf Also, another web site that can help in the location of the comet can be found at http://heavens-above.com. Simply follow the instructions at this web site by entering your observing location under "Configuration" (Philadelphia is close enough for all of SE PA) and then enter Comet Lovejoy under "Astronomy" for a particular time.