Building Big Elliptical Galaxies’ Cores

Astronomers are tracking down the seeds that likely grew to become today’s most massive elliptical galaxies.

Do Exoplanets Transform Between Classes?

A new analysis suggests that hot super-Earths might be the skeletal remnants of hot Jupiters stripped of their atmospheres.

Laniakea: Our Home Supercluster

Measurements of thousands of galaxies’ motions toward and away from us reveal that the Milky Way sits on the edge of a gigantic supercluster of galaxies.

OBSERVING HIGHLIGHTS

A Worldwide Night of Moonwatching

International Observe the Moon Night is an event that encourages people to “look up” and enjoy our nearest neighbor. This year’s InOMN is Saturday, September 6th.

Tour September’s Sky: Farewell to Saturn

The astronomical calendar says autumn arrives on September 22nd. It’s a season of transition, with plenty of celestial comings and goings in the evening sky.

See Saturn’s Moon Rhea Hide a Star

Watch as the moon Rhea steals a star from the sky for nearly a minute on September 12th.

This Week’s Sky at a Glance, September 5-13

Sky & Telescope’s weekly celestial-events calendar, with sky charts, offers selected astronomy sights for your unaided eyes, binoculars, or a telescope.