Monday, September 9, 2013

Sky Events September 2013

Moon Phases

Thu., September 5, 7:36 a.m. EDT

New Moon

The Moon is not visible on the date of New Moon because it is too close to the Sun, but can be seen low in the east as a narrow crescent a morning or two before, just before sunrise. It is visible low in the west an evening or two after New Moon.

Thu., September 12, 1:08 p.m. EDT

First Quarter Moon

The First Quarter Moon rises around 2:30 p.m. and sets around 12:20 a.m. It dominates the evening sky.

Thu., September 19, 7:13 a.m. EDT

Full Moon

The Full Moon of September is the Full Moon closest to the equinox on September 22, so is called the Harvest Moon. It rises around sunset and sets around sunrise, the only night in the month when the Moon is in the sky all night long. The rest of the month, the Moon spends at least some time in the daytime sky.

Thu., September 26, 11:55 p.m. EDT

Last Quarter Moon

The Last Quarter Moon rises around 11:50 p.m. and sets around 3:00 p.m. It is most easily seen just after sunrise in the southern sky.

Observing Highlights

Tue.–Tue., September 3–17, before morning twilight

Zodiacal Light

This faint light reflected from countless pieces of interplanetary material will be visible in dark skies for the next two weeks. It rises in a conical shape along the ecliptic before morning twilight.

Sun., September 8, sunset

Venus and the Moon

The thin waxing crescent Moon passes just south of the bright planet Venus, low in the western sky just after sunset. Spica is to their right and Saturn is to their left.

Mon., September 9, before morning twilight

Mars in the Beehive

The planet Mars appears against a glittering background of stars as it poses in front of the Beehive star cluster, Messier 44.

Thu., September 19, just after sunset

Saturn and Venus

Saturn and Venus will be in conjunction, best seen shortly after sunset. Spica and Mercury will probably be lost in twilight for northern observers, but will be better placed in the southern hemisphere.

Sun., September 22, 4:44 p.m. EDT


The Sun crosses the celestial equator moving from north to south, heralding the beginning of autumn in the northern hemisphere.

Wed., September 25, just after sunset

Mercury and Spica

Observers in the southern hemisphere will see Mercury pass close to the bright star Spica about half an hour after sunset. Venus and Saturn ride high above them.


Mercury is well placed in the evening sky for observers in the southern sky, but very low for northern observers.

Venus is now a bright “evening star” setting just after the sun.

Mars is now a bright object in the morning sky. Mars is in Cancer, passing in front of the Beehive cluster on September 9.

Jupiter is the brightest object in the morning sky all month. It is located in Gemini.

Saturn is low in the southwestern sky as dusk falls, and sets around 9 p.m. It is located in Libra all month.

Uranus is in Pisces, heading for opposition on October 3. It is visible most of the night.

Neptune, just past opposition, is visible in Aquarius all night.

Geoff Gaherty
Starry Night Software Support
All graphics © 2013 Starry Night Software