Astronomers Discover 562 New Candidate Strong Lenses With Machine Learning

An international research collaboration trained computers to sift through millions of images for cosmic treasure.

The Comet-Asteroid Chiron Has Rings — And They're Changing

A series of stellar occultations has provided evidence that the ring system around this outer solar system object is evolving drastically.

Dark Halos and Warped Disks

Galaxies are embedded within halos of dark matter, and the tilt of those halos can affect the galaxy’s stellar halo and stellar disk.

This Week's Sky at a Glance, December 8 – 17

Before and during dawn Saturday morning the 9th, catch the lovely meetup in the eastern sky of Venus and the thin crescent Moon: Astarte and Diana, respectively, for the classically minded or those who remember their pre-dawn Edgar Allan Poe.

Asteroid to Cover Betelgeuse on Night of December 11-12

Astronomers are gearing up for an unusual celestial event: an asteroid’s occultation, or total covering, of an iconic star.

Get Ready to Greet the Geminid Meteor Shower!

The year’s most spectacular meteor shower is upon us. Prepare to enjoy the Geminids under a dark, moonless sky, when you might see more than 100 meteors per hour.

December Podcast: A Tower of Brilliant Stars

This month’s Sky Tour podcast introduces you to a “tower of brilliance” in the eastern evening sky, along with tips for finding four planets and watching mid-December’s impressive Geminid meteor shower.

The New Discoveries at Stonehenge

Sky & Telescope Senior Editor J. Kelly Beatty and Roundtable present a live, virtual course on the mysteries of Stonehenge. Some 5,000 years ago, a Neolithic civilization in southern England erected the world’s most famous standing-stone monument. Yet why and how it was constructed remains a mystery. This course will explore how teams of geochemists and anthropologists are learning crucial new details about when — and why — this iconic monument came to be.