What’s up in the night sky: September 2023

Welcome to our night sky monthly feature where we focus on easy and fun things to see in the night sky, mostly with just your eyes. This month: evening giant planets, super bright Venus in the predawn, and the Moon being social and super.

All month: Yellowish Saturn is up in the east as the Sun sets, then rises high in the sky throughout the evening.

All month: Very bright Jupiter rises in the mid-evening east and is easy to see as it gets higher in the sky as the hours pass.

All month: Super bright Venus is low in the east before dawn, getting higher as the weeks pass.

Second half of the month: Mercury is low to the eastern horizon before dawn. 

Aug. 31: Full Moon, supermoon, and blue Moon. The so-called supermoon refers to the full Moon being near the closest point to Earth in its orbit. As a result, the Moon may look slightly larger and brighter than usual. A blue Moon is commonly defined as the second full Moon in the same month, which doesn’t happen often, hence the phrase ‘once in a blue Moon.’

Sept. 3-4: The Moon is relatively close to Jupiter in the sky.

Sept. 11: The crescent Moon is relatively close to Venus in the sky in the predawn east.

Sept. 22: Mercury is as high up in the  predawn east as it gets for this viewing period, though it is still quite low. It is far below the much brighter Venus.

Sept. 23: September Equinox. The Sun is over the equator and there will be approximately the same amount of daytime and nighttime wherever you are. This begins fall (autumnal equinox) in the Northern Hemisphere and spring (vernal equinox) in the Southern Hemisphere.

Sept. 26: The Moon is relatively close to Saturn in the sky. 

Sept. 29: Full Moon. This is also a so-called supermoon because the Moon is near the closest point to Earth in its orbit. As a result, the Moon may look slightly larger and brighter than usual. This is the last of four supermoons in a row.

You can get weekly sky updates as well as weekly trivia and Random Space Facts in the What’s Up segment of Planetary Radio.