AstroCal – January 2025
Happy New Year! Evening planetary viewing this month will be great so let’s jump right to the star of the show, Venus. Found in the SW to WSW part of the sky, Venus will be shining at a spectacular mag. -4-4, it will be hard to miss. Setting 4 hours after sunset, Venus will provide an optimal early evening object as it races toward greatest elongation on January 9. Greatest elongation marks the point where a planet is farthest from the Sun (in this case, Venus will be 47 degrees E of the Sun). Venus is ‘coming around the mountain’ so to speak as it moves rapidly toward the Earth. A telescopic (or binocular) view will show the disk to be half full and spanning 25” (arcseconds) on Jan 11. With a top speed of 690,000 miles per day, it will be possible to see big changes in our view of our cloud covered ‘twin’ over the next ten weeks.
Moving 16 degrees to the upper left of Venus on January 1, we find Saturn at mag. +1.1 (remember, the width of your clenched fist held at arm’s length covers about 10 degrees). Venus will pass just 2.2 degrees north of Saturn on Jan 18. By Jan 31, Saturn will be 11 degrees below Venus. A telescopic view of Saturn’s Rings will show them ‘closing’ from 4 degrees from edge on (Jan 7) to 3 degrees by Jan 28.
Much fainter Neptune (mag. +7.9) is located in Pieces, the Fish and Uranus (mag. +5.7) will be near the Taurus – the Bull / Aries – the Ram border this month. An excellent guide for finding these two outer planets can be found at abramsplanetarium.org/msta/ .
As we continue to move to the east, we can find Jupiter shining at mag. -2.7 in Taurus. High in the SE sky, Jupiter will be the brightest object in that area of the sky. Jupiter will be 5.1 degrees north and slightly Eof Aldebaran on Jan 30, just four days before it ends four months of retrograde motion.
Mars, located in Cancer – the Crab, rises in the ENE 1 ¼ hour after sunset. By Jan 12, the Red Planet will have retrograded into Gemini – the Twins and rise around sunset. On Jan 15, Mars will be at its closest point to the Earth (59.7 million miles) in opposition. Showing a disk of 14.6 arcseconds across, it will reach maximum brightness of mag. -1.4 during the second week of the month. Look for the occultation of Mars by the Moon on Jan 13. Mars will also line up with Castor & Pollux (The ‘Twins’ in Gemini – the Twins) in the dusk and dawn skies of Jan 17. Watch for the Polar Ice Cap to continue shrinking as Mars moves toward its summer solstice on May 29. Mars can also be seen above the WNW horizon in the hour before sunrise.
On New Year’s Day, look for the Young Crescent Moon low on the western horizon in the hour after sunset. The Crescent Moon will climb higher each night but still be below bright Venus until Jan 3. The First Quarter Moon (Jan 6), Full Moon (Jan13), Last Quarter Moon (Jan 21) round up the current Lunar phase with the next New Moon taking place on Jan 29. Look for the Moon to be within the Pleiades open star cluster (in Taurus) on Jan 9.
If one visits the magazine section at the Ontonagon Township Library, copies of The Planetary Report are available for your perusal. This official publication of The Planetary Society comes out four times a year coinciding with the dates of the Winter and Summer Solstices and the Spring and Fall Equinoxes. It is a great way to keep up with the latest trends in planetary exploration. If you like to enter contests, the inside back cover always offers readers a chance to win a free Planetary Radio T-shirt by simply answering a space based trivia question. Yours truly won one of these coveted trophies a few years ago when my correct answer was pulled out during a random drawing taken from all the correct respondents. The Winter Solstice 2024 issue is the latest edition available and features some remarkable photographs from the past year.
Compiled by Ken Raisanen of WOAS-FM – information provided by Abrams Planetarium Sky Calendar, Michigan State University. More information and subscription information can be found on their website at http://abramsplanetarium.org/skycalendar/ or on Twitter at http://twitter.com/AbramsSkyNotes. Yearly subscriptions cost $12 and can be started anytime.
Top Piece Video – Happy 2025 to you all – nothing says NYD like U2!