TELESCOPIC HIGHLIGHTS


This shows the position of Comet 46P/Wirtanen from December 9 (marked by animated comet) on the right side of this chart to January 1 (small dot at the left center border). Many computerized telescopes have updates that you can load onto the computer's database to show the predicted position of new and reoccurring comets. If your telescope doesn't have that capability, you can search the Internet for the ephemeris of Comet Wirtanen. A good place to start is theskylive.com. There, you can get the most current RA and DEC of Wirtanen and position the setting circles on your telescope mount to find the comet. Of course, if Wirtanen reaches or exceeds its predicted brightness, you can find it easily by just scanning the sky and centering it in your telescope's finder scope.
Many astronomers love to image the famous Great Orion Nebula (M42) lit up by the many hot young stars that inhabit it, but did you know that a speedy super hot star probably was ejected from M42's Trapezium star cluster? This star (AE Aurigae) is almost solely responsible for illuminating the nebula shown in this image. The gas in the cloud glows primarily in Hydrogen Alpha (HA) red light and reflects in blue and ultraviolet light off of snake-like tendrils of dust. The Flaming Star Nebula (cataloged as IC 405, SH 2-229, or Caldwell 31) is about 1,500 light years away. This is about the same distance estimated to the Orion Nebula, so AE Aurigae must've made a lateral move to its new temporary home. We're fortunate to see this star in its present position. It is moving so fast through the nebula that it's forming a bow shock in its direction of motion and will be completely through the gas and dust cloud in "only" 20,000 years. After that, the nebula will cool down and glow no more...unless...AE Aurigae causes enough turbulence and distortion to collapse denser portions of the nebula into new stars. This chart is dated December 10 because it's the last day after the beginning of the month that there won't be any interference from the Moon's glare. After this night, you'll have to wait until after Christmas to view dim deep space objects without the Moon getting in the way.
For those of us living in the southern latitudes of the United States, December is the best month to view the Sculptor Galaxy Group. The two largest galaxies in this group are marked in this image. The Sculptor Galaxy (NGC 253) is by far the largest and brightest visible in even small telescopes. NGC 247 is the next "big kid on the block." Both these galaxies are bright enough to take magnification well, so don't hesitate to use higher power eyepieces to "blow them up" once you locate them. For those without computerized telescopes, use the bright guide star Deneb Kaitos (also cataloged as Diphda, Beta Ceti, HIP 3419, and HR 188). It is the second brightest star (magnitude 2) in the constellation Cetus The Whale and is located just above and slightly to the right of NGC 247 in the above image. From Deneb Kaitos, you can scan downward to see the Sculptor galaxies. If you live in a dark sky area, you may be able to see these galaxies through 10x50 binoculars. However, I strongly suggest that you mount the binocs on a camera tripod to stabilize your FOV.