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Star Trak: September 2020

For immediate release: September 1, 2020

BLOOMINGTON, Ind. -- Mars will brighten and appear larger during September as it makes its closest approach to Earth. It will rise about two hours after sunset as the month begins and less than an hour after sunset at month's end.

Starting the month half as bright as Jupiter, Mars will be a bit brighter than the largest planet by month's end. Its red-orange glow will stand out in a part of the sky lacking bright stars. The best telescope views will be after midnight, when the Red Planet will be nearly 60 degrees high for mid-northern latitudes in the United States.

The two giant planets, Jupiter and Saturn, will shine together in the constellation Sagittarius during September. They will be highest in the south a few hours after sunset as the month begins and during evening twilight by month's end.

The two planets have been slowly moving apart for several months, but in September the gap between them will start to shrink. Both planets will fade slightly during the month, but they will still be bright and large enough for detailed viewing with telescopes. Saturn's rings will be tilted toward Earth at an angle of 23 degrees. Titan, Saturn's largest moon, will be due north of the planet on Sept. 1 and 17 and due south on Sept. 9 and 25. Any telescope will show Jupiter's four bright moons, first seen by Galileo.

Venus will rise more than three hours before sunrise throughout September, reaching an altitude of nearly 40 degrees for mid-northern observers. It will start the month in the constellation Gemini, cross the constellation Cancer, and be near the bright star Regulus in the constellation Leo by the end of the month.

Mercury will be very low in the western sky during September, setting less than an hour after the sun for observers at mid-northern latitudes.

Equinox

The sun will arrive at the September equinox on Sept. 22 at 9:31 a.m. EDT, marking the start of autumn in the Northern Hemisphere and spring in the Southern Hemisphere. For the next six months in the Northern Hemisphere, the nights will be longer than the days.

Moon phases

The moon will be full on Sept. 2, at third quarter on Sept. 10, new on Sept. 17, and at first quarter on Sept. 24.

Author: Hal Kibbey Email: hkibbey [at] gmail.com

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