Welcome to the University of Texas Skywatchers Report for Monday December 16th, 2024, through Sunday January 5th, 2025.
The moon is at third quarter on Sunday December 22nd, so we’ll have a waning gibbous moon all of the week of December 16. We will then have a waning crescent moon in the pre-dawn skies until we reach the New Moon on December 30. We’ll finish 2024 with the moon beginning the waxing crescent phase until we reach first quarter on Monday January 6th.
Over the remaining two weeks of the year, we’ll see Venus appear slightly higher in the southwest each night after sunset as it gradually decreases in percentage illuminated but increases in angular size and overall brightness. Venus will set at 9 p.m. in mid-December and 9:25 p.m. at the end of the first week of January. Look for Venus to pair up with the thin crescent moon on January 3rd.
Saturn is moving back towards the sun and its next solar conjunction in March of 2025, but we’ll still see it in the southwest after sunset to end 2024 and start 2025. Saturn is setting at 11:30 p.m. on December 16th and 10:20 by January 5th. Look for Saturn below the crescent moon on January 4th.
Jupiter is shining brightly in the east at sunset and is setting a little before dawn in mid-December and a little after 5 a.m. in early 2025.
Mars is rising at 8:25 p.m. on December 16th and at 6:35 p.m. by January 5th, just one week before its closest approach to Earth. Over that time, Mars will go from -0.9 magnitude in brightness and 13 arcseconds in size to -1.3 magnitude and 14.5 arcseconds in size. Look for Mars near the moon on the night of Tuesday December 17th.
Mercury is rising at 5:50 a.m. in mid-December and then will reach greatest elongation on December 24th, when it rises at 5:45 a.m., about an hour and 40 minutes before sunrise. By January 5th, Mercury will be rising at 6:05 a.m., still over an hour before sunrise. A very thin crescent moon will be near Mercury on the morning of December 28th.
The winter solstice for the northern hemisphere occurs at 3:21 a.m. on Saturday December 21 in Austin when we will experience our lowest amount of daylight for the year at 10 hours and 11 minutes. Compare that to the 14 hours and 6 minutes we have at the summer solstice in June.
Public viewing on the UT campus telescopes has finished for 2024. Spring semester viewing will start in the second half of January 2025.
Thank you for calling the University of Texas Skywatchers Report.
