Having passed conjunction with the sun, Venus now shines brilliantly at magnitude -3.9, in the early evening in the southwest sky. As the month progresses, Venus will reach a rendezvous with Saturn on the 22nd and 23rd. The two planets will be less than ½ degree apart. Saturn, at magnitude +0.8, will be difficult to pick out visually next to very bright Venus. Good binoculars may be needed to see both planets.
For a one evening planetary parade try the following. On a clear night early in the month, start by looking to the west-southwest. There you will find Venus hovering just above the horizon. Looking eastward about 23 degrees you see the ringed planet Saturn. Looking another 40 degrees or so eastward, you’ll find Jupiter positioned due south from overhead. Looking eastward about 60 degrees from Jupiter, you’ll be able to see Mars. To aid you in calculating degrees, use the following method. Make a fist and fully extend your arm. The width of your fist at arm’s length is about 10 degrees. Invite your neighbors out and show them the planetary parade!
Beginning around the middle of the month Mercury begins a morning apparition rising about one and a half hours before sunrise. It reaches its greatest elongation and height above the southeastern horizon on the 30th.
If you missed last month’s occultation of Mars by the moon, you are in luck. The moon is poised to do it again on the night of January 30-31. For New Mexico, first contact of the dark lunar limb will be at 10:04 p.m. MST and take a minute or so to completely cover the planet. Mars will reappear from behind the bright limb at 10:45 p.m. This occultation favors the southeastern and southwestern states. For information about timings in your area go to www.lunar-occultations.com.
The moon will be full on the 6th, last quarter on the 15th, new on the 21st, and first quarter on the 28th. Looking to the southeast on the 3rd, high in the sky and shortly after dark, the waxing gibbous moon will be to the left and just below Mars. Looking southeast on the morning of the 19th, about 45 minutes before sunrise, the waning crescent moon will be to the right of Mercury. Looking southwest on the 23rd, about 30 minutes after sunset, we get a double treat with the new crescent moon hanging just above Venus and Saturn with the two planets being separated by about ½ degree. Looking to the southeast and almost overhead on the 30th, the moon once again visits Mars, being found just to the right of the red planet.
On January 4, the Earth will reach perihelion, its closest approach to the sun for 2023, at a distance of 147.1 million kilometers or 91,341,565.3210 miles!
There will not be a first Saturday star party at the Etscorn Campus Observatory this month.
New Mexico Tech Astronomy Club