skywatchers report

Welcome to the University of Texas Skywatchers Report for Monday December 18, 2017 through Tuesday January 2nd, 2018

The moon is new on Monday December 18th and will be in a waxing crescent phase until it reaches first quarter on Tuesday December 26th. Then the moon will be in a waxing gibbous phase until it reaches full late on Monday January 1st. The full moon of January is known as the Old Moon, the Moon After Yule, and the Wolf Moon. This first full moon of 2018 will also be the largest in angular size of the year since it occurs just a few hours after the moon is at its closest point to the earth, known as perigee.

The winter solstice for the northern hemisphere occurs at 10:28 a.m. US central time on Thursday December 21st. This is the point where the sun reaches its farthest point south of the celestial equator and cuts the smallest daytime arc across our sky, creating the shortest amount of daylight. In the southern hemisphere the opposite occurs and they receive the longest amount of daylight for the year.

Saturn is in conjunction with the sun on the 21st and with that, all of the planets visible to the unaided eye will be in our morning skies for a few weeks.

Mars is rising at 3:25 a.m. on December 18th and at 3:10 a.m. to start the new year. Jupiter follows next rising at 4:05 a.m. on the 18th and 3:20 a.m. by January 1st.

Mercury is at greatest elongation from the Sun on January 1st and then will begin to move back towards the sun as we progress through January. Mercury is rising at 6:20 a.m. on December 18th and 5:45 a.m. on New Years Day.

Venus is headed towards conjunction with the sun early in 2018 so it is rising just 20 minutes before the sun on December 18th and only 5 minutes before sunrise on January 1st. Venus and Saturn will be very close to one another on December 25th, but too close to the sun to see.

Public viewing on UT campus telescopes has finished for the Fall 2017 semester. Spring semester viewing will start in the latter half of January 2018.

Thank you for calling the University of Texas Skywatchers Report and have a Happy New Year!