September Night Sky
Tonight’s Sky: September 2015
Your guide to constellations, deep-sky objects, planets and events, Tonight’s Sky, Highlights of the September Sky
September Evening Planets
After nightfall, catch Saturn in the southwestern sky. Use a telescope to get a better view of the ringed planet before it disappears beneath the horizon.
September Constellations and Deep-Sky Objects
September nights feature the “wet quarter” of the sky. Two neighboring constellations bear ancient references to water.
Aquarius is one of the oldest constellations, recognized even by early civilizations. In ancient mythologies, Aquarius is the god of the waters. Look for the Water Jar, a group of stars
shaped like a Y.
A rich, compact cluster of stars can be seen in Aquarius.
Known as M2, it contains about 150,000 stars located about 37,500 light-years away.
Binoculars present it well, but a small telescope reveals much more detail in the cluster’s compact center.
Nearby lies the great constellation Capricornus. Known in mythology as the Water Goat, it represents a creature that fed and watered the infant Zeus, ruler of the Greek gods.
Algedi is the brightest star in Capricornus. It’s visible in binoculars as an elongated star.
This odd shape is due to a visual trick. From our distant vantage point, two unrelated stars appear to be close together.
Capricornus also hosts a dense cluster of stars, M30. A small telescope easily resolves individual stars in the cluster.
September Morning Planets
Mars and Venus grace the eastern sky before sunrise.
During the second half of the month, Jupiter joins them in the pre-dawn sky.
A telescope will provide a better look at the planets.
On September 27th in the Americas (September 28th in Europe, Africa, and western Asia) the Moon will pass through Earth’s shadow, creating a lunar eclipse.
The Moon will appear to darken during the eclipse.