Welcome to the University of Texas Skywatchers Report for Monday December 12th through Sunday December 18th.
The moon is at third quarter on the night of Thursday the 15th so we’ll have a waning gibbous moon for the first half of the week and a waning crescent moon in the pre-dawn skies for the remainder of the week.
Venus is very low in the west at sunset and is setting a little less than an hour after the sun. Mercury is near Venus and is setting at 6:50 p.m.
Saturn is now in the southwest at sundown and is setting at 9:50 p.m. Jupiter is up in the south and is setting at 12:55 a.m.
Mars is up in the east as darkness falls and is setting at 6:45 a.m. Mars is now at magnitude -1.7 and is at 16.5 arcseconds in size, so it is just a little bit dimmer and smaller than it was at closest approach at the beginning of the month.
The Geminids meteor shower peaks on Wednesday the 14th with the best viewing coming early that morning, although this year’s shower will have interference from the waning gibbous moon. The Geminids get their name because they appear to come from a point in the constellation Gemini the Twins, which is fully above the horizon by 8 p.m. and are caused by the Earth passing through the orbital debris of the object 3200 Phaethon. Phaethon is classified as a Palladian asteroid, making the Geminids one of only two meteor showers not associated with a comet (the other being the Quadrantids). At its peak, the Geminids often produce over 100 meteors an hour under dark skies.
In space anniversaries this week, Wednesday December 14 marks 60 years since the Mariner 2 spacecraft achieved the first successful flyby of another planet when it came within a little less than 19,000 miles of the cloud tops of Venus. The last signals from Mariner 2 were received three weeks later and the spacecraft remains in a heliocentric orbit.
Public viewing on UT Campus telescopes has finished for the Fall 2022 semester. Spring 2023 semester viewing will start in mid-January. Please check back for details on starting dates and times.
Thank you for calling the University of Texas Skywatchers Report.
