Welcome to the University of Texas Skywatchers Report for Monday September 21st through Sunday September 27th.

The autumnal equinox for the northern hemisphere occurs on Tuesday September 22nd at 7:05 p.m. here in Austin when the sun passes the celestial equator, and the amount of daytime and nighttime are roughly equal. After the equinox, the nights will start to become longer than the days until we reach the winter solstice in December.

The full moon for the month of September is on Saturday the 26th, so we’ll have a waxing gibbous moon for most of the week. This full moon is known as the Fruit Moon, the Corn Moon, the Barley Moon, and, as the full moon closest to the Autumnal Equinox, it is this year’s Harvest Moon.

Mercury is low in the west at sunset and will be a degree from the bright star Spica in the constellation Virgo on Friday when both will set at 8:15 p.m.

Venus continues to shine very bright low in the west-southwest at sunset and is setting at 8:40 p.m. at midweek. A view in a telescope now shows Venus is only 20% illuminated and looks like a tiny crescent moon.

Saturn is rising at 8 p.m. at midweek and will be below the full moon on Saturday night.

Mars is rising at 2:20 a.m. this week and is in a line with the bright stars Castor and Pollux in the constellation Gemini the Twins.

Jupiter is rising at 4 a.m. this week, now over three hours before sunrise.

Public viewing at the Physics, Math, and Astronomy building is on Wednesday nights currently from 8 to 10 p.m. PMA 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 currently from 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. Take the elevator to the 5th floor then take the stairs up to the 6th floor and follow the signs up to the telescope.

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 star party status information, which is updated 30 to 45 minutes before the scheduled viewing start times.

Thank you for calling the University of Texas Skywatchers Report.