Mercury is very low in the West after Sunset. The planet is losing altitude and brightness fast. The planet is becoming difficult to see. Around 11 September, Mercury moves into the bright glow of Sunset and is lost from view.
Saturn is well up in the SSE as evening twilight fades. The planet is fairly well placed for evening observations. The planet brightness stays the same for the whole month.
Jupiter rises about 1 hour after Sunset during the 1st week of September. This bright planet rises in the East. Each evening, Jupiter is rising earlier and earlier. By the 26 September, Jupiter is up just after Sunset. This is the closest approach of Jupiter to Earth since 1952. Jupiter is now the brightest planet in the evening sky and will put on a fine evening show.
Mars now manages to rise about 1 hour before Midnight in the NE. The planet has made the move and becomes an evening planet. Mars also has moved into the Constellation of Taurus where it will stay for the rest of the year. As the month progresses, Mars increases in brightness. Mars is slowly positioning itself for an excellent evening showing a few months from now.
Venus, the sole bright morning planet rises less than an hour before Sunrise in the East. Each morning, Venus is losing altitude fast and is getting lower into the bright glow of Sunrise. Around 12 September, Venus moves into the bright glow of Sunrise and is lost from view. Venus will not make another appearance until December in the evening sky.
8 Sep Saturn above the Moon, Evening
10 Sep Full Harvest Moon
11 Sep Jupiter above the Moon, Evening
17 Sep Moon above Mars, Dawn
18 Sep Last Quarter Moon
20 Sep Bright star Pollux above the Moon, Pre-Dawn
22 Sep Autumnal Equinox
26 Sep Jupiter close approach to Earth
September’s Last Quarter Moon:
On the early Dawn morning of 18 September, the Last Quarter Moon will be visible high in the sky. September’s Last Quarter Moon is the best one of the year. This Moon very high position in the sky puts it into an excellent position for telescope observations. Even binoculars will show a few of the largest lunar features.
Jupiter’s Epic Showing:
On the evening of 26 September, the planet Jupiter comes closest to Earth than it has been in the past 70 years. The planet is a its maximum brightness and will put on a fine evening show. The prime observing window to see Jupiter at his best is from 1 September to 1 November. During this prime observing window, this will be an excellent time to observe Jupiter in a good telescope. Binoculars will show the planet’s four brightest moons but you really need a good telescope to see the planet’s cloud details. If seeing conditions are right; Jupiter’s cloud belts will reveal their colors and fine details. Jupiter’s 4 brightest moons will reveal their disks and sublime colors. After this prime observing window, you won’t be able to see Jupiter this close to Earth and this bright for another 83 years. So hopefully you can treat yourself to a telescopic view of Jupiter.
Gary T. Nowak
Vermont Astronomical Society