September’s equinox takes place on the 22nd at 10:29 p.m. Eastern Daylight Time. At that moment the Sun shines directly overhead as seen from the equator. Days and nights are both 12 hours long — that’s where the word equinox comes from — and no matter where you live the Sun rises due east and sets due west.As darkness falls on September 1st, look for the planets Mars and Saturn to the Moon’s lower right. At month’s end, the Moon will have gone through nearly a complete cycles of phases and return to this stretch of sky. But by then Mars and Saturn will have shifted somewhat. Look for a very thin crescent Moon to Saturn’s right on the 27th. The ringed planet will soon sink from view..