Sunrise and Sunset Times
Eastern Daylight Time from the U.S. Naval Observatory
Sun rises at 6:29 a.m. and sets at 7:33 p.m. on the 1st
Sun rises at 6:57 a.m. and sets at 6:45 p.m. on the 30th
Moon’s Phases in September
New Moon on the 9th
Full “Harvest” Moon on the 24th
Stars and Constellations
Autumn officially arrives in the Northern Hemisphere on Sept. 22 at 9:54 p.m. Eastern Daylight Time, but the first three-quarters of September belong to summer.
Indeed, the stars of summer are still well placed for viewing during the early evening hours. Low in the southwest is orange-red Antares, often referred to as the “heart” of the constellation Scorpius, with the planets Jupiter and Saturn located to its west and east, respectively. To Antares’ far lower left are a pair of unequally bright stars, Shaula and Lesath, known as the “Cat’s Eyes.”
To the east of Scorpius is Sagittarius, the Archer, which is often identified by its “Teapot” asterism, and directly above Scorpius is Ophiuchus, the Serpent Bearer, whose left (eastern) foot juts between the Scorpion and the Archer.
Following Sagittarius to the east is the dim constellation of Capricornus, the Sea Goat. Scorpius, Ophiuchus, Sagittarius and Capricornus are all zodiac constellations, which means that the Sun treks within their boundaries during the course of the year, roughly from late November through mid-February. Of course, during this time interval, these constellations are up during the daytime, and so the overpowering glare of the brilliant Sun prevents them from being seen.
Standing nearly overhead during the early evening hours of September is another hallmark of summer, the Summer Triangle, composed of Vega in Lyra, Deneb in Cygnus and Altair in Aquila. The Summer Triangle is ideally situated for evening viewing in late summer and early autumn; during September, all three of these stars remain well above the horizon until well after midnight. Interestingly, the bright easternmost star of the Spring Triangle, orange-colored Arcturus in the constellation Boötes, the Herdsman, is still up in the west. Arcturus sets after 10:30 p.m. EDT in mid-September.
Later at night after the stars of summer have migrated toward the western half of the sky, the first stars of autumn are emerging in the eastern sky. Rising above the southeastern horizon after about 10 p.m. EDT is the white star Fomalhaut, which lies in the constellation of Pisces Austrinus, the Southern Fish. Also due east at about this time is the Great Square of Pegasus, four stars in the form of a rectangle lying on its edge. Low in the northeast is the famous “W” shape of the constellation Cassiopeia, the queen of ancient Ethiopia. The “W” opens up toward Polaris, the North Star, so that is one way of locating it.
Naked-Eye Planets in the Evening and Morning Sky
Venus gleams like a yellow gem in the western sky at dusk. The spectacular evening “star” reaches its peak brightness late this month. Unfortunately, Venus now hovers pretty low above the western horizon at dusk. On the 1st, Venus, accompanied by the much fainter true star Spica to its right, sets about an hour and a half after sunset, or 9 p.m. EDT. By month’s end, Venus sets less than an hour after the Sun; at this time, a telescope will reveal a distinctly crescent phase like the Moon’s. Venus will vanish entirely from the evening sky during October, only to reappear prominently in the early morning sky in November.
Jupiter continues as a brilliant golden “star,” beaming low in the southwest at nightfall. Jupiter sets around 10 p.m. on Sept. 1 and shortly after 8:30 p.m. on the 30th.
Far to the east of Jupiter, Saturn resembles a bright cream-colored star among the fainter, true stars of the constellation Sagittarius. As September opens, Saturn stands nearly due south at nightfall and sets at about 1 a.m. By month’s end, Saturn is setting by around 11:15 p.m. A telescope will reveal Saturn’s magnificent ring system.
Brilliant, orangish Mars is up in the south-southeast at nightfall. Mars outshines Jupiter in early September, but it loses roughly half of its brightness by the end of the month as the Earth-Mars distance continues to widen. Consequently, Mars drops to thirrd brightest among the planets, while Jupiter moves back up to its usual rank of second brightest (after Venus). Mars sets a few minutes before 3 a.m. on the 1st and around 1:30 a.m. on the 30th.
Mercury is visible as a “morning star” during the first week or so of September; look low in the east at dawn for a bright, yellow “star.” Binoculars will greatly help. Afterwards, Mercury vanishes into the dawn glow and will reappear in the evening sky at the end of October.
Information on lunar phases and rise/set times of Sun and planets is obtained from the U.S. Naval Observatory Data Services at usno.navy.mil/astronomy. Additional information comes from “The Astronomical Almanac (2016-2020)” by Richard J. Bartlett (Stars ‘n Stuff Publishing, 2015). For more information on the night sky, visit the Widener Observatory Stargazing website at widener.edu/stargazing. A set of free sky maps can be obtained at skymaps.com.