Sep 17

What’s Up in the Sky

September Offers Viewing Choices

If variety is the spice of life, then September’s dark skies might be described as the oregano of autumn. Lots of interesting, simple events will happen this month, and they will be easy to miss unless you know when and where to look. But then, that’s why you read this column so you’re all set.
August has its “Blue Moon” (the second Full Moon during the calendar month) this Friday, but September has the Harvest Moon, the Full Moon closest to the first day of autumn, so named because its light is useful for several consecutive nights during the harvest. This year that falls on September 29.
For reasons that stem from the geometry of the orbits of Earth and the Moon, in September, for several days before and after being Full, the Moon rises less than 30 minutes later each night. In March, by contrast, it is over an hour later. That means its light is useful to farmers harvesting their crops for a number of consecutive nights.
Another easy observation is to watch the Sun rise or set on the autumnal equinox (first day of autumn), which is on September 22 this year. The Sun rises due east and sets due west on that day. This is a great urban observation in an area with streets that run east-west, although it can be bothersome if you are driving into it. Watch for several days before and after the equinox and see if you notice any difference in the point on the horizon where it rises or sets.
For two weeks starting September 14 look for the Zodiacal Light one and a half to two hours before sunrise. Look for a broad, tall, rightward-leaning pyramid of light rising from the eastern horizon just below Venus.
Early risers will also enjoy Jupiter right above the Last Quarter Moon on the morning of Sept. 8 and Venus next to the Crescent Moon on the 12th.
On the 19th, look low in the SW 35 minutes after sunset for Mars just to the right of the Crescent Moon.

This month offers quite a variety up in the sky.

This month in history:
Sept. 3: Last two Apollo Moon landings canceled by NASA – 1970
Sept. 8: Voyager 1 launched – 1977
Sept. 18: Photo of Earth and Moon together in space taken by Voyager 1 – 1977
Sept. 21: Gustav Holst born – 1874
Sept. 23: Premier of “The Jetsons” – 1962
Sept. 26: Hyperion, a moon of Saturn, discovered by William Bond = 1848