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September 5: Titan near Saturn
The waning crescent Moon lies in Gemini today, not far from the 3rd-magnitude star Epsilon (ε) Geminorum, roughly around where western twin Castor’s knee would be. Mars is also in Gemini, closer to the midsection of the eastern twin, Pollux. You can catch the lovely celestial pairing early this morning: Mars rises around 2 A.M. local daylight time, and an hour before sunrise, the pair has reached some 40° high in the east, with Jupiter also visible to their lower left, in the constellation Cancer.
Mars still appears pretty tiny in a telescope, just 5” across. It will slowly grow larger over the coming months as its distance from Earth decreases, but for now, surface detail is impossible to see. However, you can easily note its reddish color — compare that to, say, white-hued Castor and yellow-hued Pollux, the bright stars marking heads of the Twins.
Closer to the horizon, brighter Jupiter is sitting in eastern Cancer about 7.2° east of M44, the Beehive Cluster. Through a telescope, the gas giant stretches an impressive 32” and is flanked by its Galilean moons. Early in the morning, Io and Callisto lie west of the world and Europa and Ganymede are to the east. Observers in the Central and Mountain time zones can try to catch Io disappearing into Jupiter’s long, dark shadow around 5:35 A.M. CDT, although the sky will be starting to brighten in the Midwest and the planet will be only a few degrees high in the Mountain time zone. Pacific Coast observers will see only the three other moons, as Io reappears right around sunrise in the Pacific time zone.
The Moon passes 3° due north of Mars this afternoon at 2 P.M. EDT, shortly before our satellite reaches perigee, the closest point to Earth in its orbit, at 4:43 P.M. EDT. At that time, it will be 228,825 miles (368,258 kilometers) away.
Sunrise: 6:32 A.M.
Sunset: 7:24 P.M.
Moonrise: 12:58 A.M.
Moonset: 4:53 P.M.
Moon Phase: Waning crescent (20%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
Alison Klesman is senior editor of Astronomy magazine. She holds a Ph.D. in astronomy and has studied a variety of topics, from minor planets to supermassive black holes.
