Welcome to the University of Texas Skywatchers Report for Monday September 19th through Sunday September 25th.

The moon is at third quarter on the morning of Friday the 23rd, so we'll have a waning gibbous moon for the first part of the week and a waning crescent moon for the weekend.

The autumnal equinox for the northern hemisphere is on Thursday the 22nd at 9:21 a.m. for those of us in the US central time zone. The equinoxes occur when the sun crosses the celestial equator and daylight and nighttime are roughly equal. Also at this time, the sun rises due east and sets due west.

Jupiter is now lost in the sun's glare as it heads towards conjunction early next week. Venus continues to climb away from the sun and is setting at 8:45 p.m. at midweek, now over an hour after the sun.

Saturn, Antares, and Mars continue to make an easy-to-spot triangle in the south-southwest at sundown. Saturn and Antares are the right side of the triangle and Mars forms the point on the left. Saturn is setting at 11:10 p.m., followed by Mars at 12:05 a.m.

Mercury is now the only planet up in the morning, although it will be joined by Jupiter in the next few weeks. Mercury is up over an hour before the run, so you might be able to pick it out of the morning twilight if you have a good view of the eastern horizon.

Public viewing at the 16-inch reflector on top of Robert Lee Moore Hall is on Wednesday nights currently from 8 to 10 p.m. RLM is located on the southeast corner of Dean Keeton and Speedway. Take the elevator to the 17th floor and follow the signs to the telescope.

Public viewing at the 9 inch refractor at Painter Hall is on Friday and Saturday nights from currently 8 to 10 p.m. Painter Hall is located on 24th street about halfway between Speedway and Guadalupe and is northeast of the UT Tower. To get to the telescope, take the elevator to the 5th floor and exit to the left. Follow the 5th floor hallway to the end and take the staircase through the double doors on the left. Once you reach the 6th floor, go to your right and follow the signs up to the telescope. Please note that there will be no Painter Telescope viewing on Saturday evenings when the UT football team has a night home game. To check the football schedule, logon to texassports.com.

All events are free and open to all ages and no reservations are required. Note that viewing times and availability change throughout the year so please check the schedule before planning a visit. Observing events are weather permitting. Please call 512-232-4265 for weather cancellation information, which is updated 30 to 45 minutes before the scheduled viewing start time.

Thank you for calling the University of Texas Skywatchers Report.