September is a time of transition. This month the autumnal equinox falls on the 22nd, as the Sun sets earlier and earlier, and northern summer gives way to autumn.
Low in the southwest at dusk, the brilliant “star” is Venus, wrapping up a terrific 7-month stint in the evening sky.
As Venus sets in the west, giant Jupiter rises in the east. This month the King of Planets reaches opposition, meaning it's opposite the Sun in the sky. It rises at sunset, gets highest around midnight, and sets at dawn.
Find out why this month's opposition is a special one for Jupiter by downloading September's audio sky tour. It's a 6-megabyte MP3 file that's about 6 minutes long.