What’s Up in the Night Sky – September 2026
from In-The-Sky.org
Moon Phases
Last Quarter – September 4
New Moon – September 10
First Quarter – September 18
Full – September 26 – The Harvest Moon
Close Encounters
September 1: Aurigid meteor shower. See major meteor shower section below for details.
September 3: The nearly last quarter Moon passes less than 2 degrees from the Pleiades in the early morning sky.
September 6 (early morning before dawn): The waning crescent Moon passes about 3 degrees north of Mars in the predawn sky.
September 8 (before dawn): The Moon and the Beehive cluster in Cancer pass about 42 arcminutes from each other. The Moon will be a thin crescent.
September 8 (early afternoon): The Moon passes in front of Jupiter in the daytime sky. The occultation begins around 1:55pm as Jupiter slips behind the Moon’s sunlit crescent and reappears around 2:55pm from behind the lunar dark edge.
September 9: September eta-Perseid meteor shower. See major meteor shower section for details.
September 14 (evening): The 3-day old Moon and Venus pass within half a degree of each other.
September 22 (evening): Venus reaches its greatest brightness in this current evening apparition at magnitude -4.6.
September 25 (all night): Neptune reaches opposition tonight, rising at sunset and setting at sunrise in Pisces. This is the optimal time to observe Neptune.
September 27 (after 11pm): The 16-day old Moon and Saturn pass about 6 degrees from each other.
September 30: The waning gibbous Moon visits the Pleiades for the second time this month, this time with a separation of about 1 degree.
Major Meteor Showers – from https://www.amsmeteors.org/meteor-showers/meteor-shower-calendar/
Aurigid meteor shower is active from August 28 through September 5 with a peak zenithal hourly rate (ZHR) of 6 around September 1. A bright gibbous waning Moon will significantly reduce the observed rate.
September eta-Pereid meteor shower is active from September 5 through September 21, with a peak ZHR of 5 around September 9. The Moon will hinder viewing early in its apparition but is negligible on and after the peak date.
Planet Watch for September 15, 2026
Mercury is lost in the Sun’s glare, separated only by about 3°.
Venus is low in the western sky and only 8° above the horizon at dusk. It sets about 1h 15m after the Sun.
Mars rises above the eastern horizon around 1:35am. Mars brightens to magnitude 1.2 in Gemini and is visible until sunrise around 6:00am.
Jupiter rises above the eastern horizon around 3:40am. Jupiter shines at magnitude -1.8 in Cancer until the Sun washes it out.
Saturn is returning to the evening sky! It becomes visible 10° above the eastern horizon around 9:00pm. The brightening ringed planet at magnitude 0.3 in Cetus reaches its highest point in the sky around 2:10am.
Uranus rises in the east around 10:20pm and reaches an altitude of about 72° above the southern horizon before dawn breaks. Uranus continues to shine at magnitude 5.7 in Taurus.
Neptune becomes accessible around 9:30pm and reaches maximum altitude of 51° above the southern horizon at 1:35am. Neptune shines faintly a magnitude 7.8 in Pisces.
