81–100 of 123 results


Planet Hunters are Losing Count

The latest 500 planet candidates from the Kepler mission are just part of the story. But Terra II remains elusive.

People, Places, and Events

Remembering Tom Gehrels (1925-2011)

Dutch-born planetary scientist and asteroid hunter Tom Gehrels passed away on July 11th. Sky & Telescope contributing editor Govert Schilling shares his memories of a unique person.

MMT Observatory

People, Places, and Events

Praising Arizona — II

S&T contributing editor Govert Schilling visits observatories in southern Arizona.

People, Places, and Events

Praising Arizona — I

S&T contributing editor Govert Schilling visits observatories in southern Arizona


COROT Finds the Smallest Exoplanet Yet

Astronomers have found the smallest transiting exoplanet yet, with a silhouette only about 1.7 Earth diameters wide. It's also the fastest-orbiting planet known, with a "year" lasting 20 hours.

Stellar Science

Standard-Candle Supernova Confusion

Type 1a supernovas are crucial for measuring how the expansion of the universe has been changing. But no one knows for sure exactly what they are.


Rain of Super-Particles

A 45-year mystery solved? Scientists using the new Pierre Auger Observatory say they've finally tracked down where ultra-high-energy cosmic rays — "tennis ball particles" — are coming from.

Big nothing in space


Cold Evidence for a Cosmic "Texture"?

A ripple in the cosmic background radiation hints at an irregularity in spacetime. . . maybe.

Astronomy and Society

The Source of the Dinosaurs' Asteroid

Did a colossal collision in the asteroid belt 160 million years ago doom the dinosaurs? A just-published analysis argues strongly for exactly that.

Milky Way

Mira's Marvelous Tail

Mira, the closest and brightest of the red long-period variable stars, has thrown off a gassy hood and a comet-like tail so big that if you could see them, they would overflow your telescope's field of view.

Solar System

A Ringside View of Uranus

Astronomers have assembled an armada of telescopes to observe Uranus in a way that hasn't been possible since the 1960s.

Professional Telescopes

The New Largest Telescope in the World

With an aperture of 10.4 meters, Spain's new Gran Telescopio Canarias is about to assume the title.

Astronomy & Observing News

Overgrown Planet, or Dwarf in the Desert?

Astronomers have uncovered a fascinating heavy object orbiting close to its star. The problem is, they aren't sure what to call it.

Astronomy & Observing News

Goodbye, Pluto. Hello, "Dwarf Planets"!

It's official: our solar system has eight planets, and Pluto is not one of them according to the International Astronomical Union.

Astronomy & Observing News

Giant Telescopes of the Future

Telescopes as large as 20, 30, and even 100 meters are now on the drawing boards.

Astronomy & Observing News

Galaxy Maps Reveal Nature of Universe

The latest results from two comprehensive galaxy surveys independently confirm the important role of dark matter and dark energy in the evolution of the cosmos.

Astronomy & Observing News

A Black Hole Swarm

In this Chandra X-ray Observatory image of the galactic center, the four labeled sources are bright and variable. They are probably binary systems consisting of a stellar-mass black hole and a normal star. The Milky Way's central black hole, known as Sagittarius A*, is the bright spot above source C.Courtesy…

Astronomy & Observing News

A Planet Found Through Asteroid Belts

Orbiting Beta Pictoris farther than Saturn orbits the Sun, an unseen planet is apparently shaping the star's asteroid belts.

Astronomy & Observing News

LOFAR: A Giant Radio Telescope Takes Shape

Fifteen thousand humble little antennas will work in concert to form one of the world's most powerful astronomical instruments.

Astronomy & Observing News

Astro News Briefs: May 31–June 6

Tiny-tiny galaxies and activity minima in Sun-like stars.