Putting Exoplanets on the Scale
Astronomers have come up with a new technique for measuring an alien planet’s mass, and therefore its composition and potential habitability, even when standard methods don’t work.

Last Chance to Enter S&T's Comet ISON Photo Contest
The "comet of the century" famously lost its battle against the Sun, but you can still enter our photo contest for a chance to win some hefty prizes. Don't miss the December 31st deadline!
Hubble Homes in on Hazy Worlds
Two teams have announced the discovery of water on alien worlds. But they found less water than expected, suggesting these planets are surrounded by a high-altitude haze.
Downsizing a Black Hole
Astronomers have revealed a supposedly monster black hole to be rather ordinary in size.
Monster Burst Challenges Theories
Observations of one of the most powerful supernovas ever recorded suggest that the standard model for gamma-ray bursts might be missing a piece of the puzzle.
Will This New Technology Transform Astronomy?
Astronomy is ready for the next generation of detectors, and superconductors are at the heart of the coming revolution.
Two Blows for Dark Matter Model
Two recent experiments limit physicists’ favorite candidate for the elusive and invisible matter lurking in the universe.
A Planetary System Out of Whack
The red giant star Kepler-56 spins on an axis offset by a bizarre 45 degrees from its transiting planets. The discovery of a third companion could explain why.
Fomalhaut Star System Actually a Triple
Turns out “the lonely star of autumn” has not just one, but two distant companions, making it one of the most widely separated systems known.
The Quest for Zodiacal Light
The first half of October 2013 is a good chance for early risers to catch the zodiacal light, the faint eastern glow preceding dawn.
Astronomer Seager Wins “Genius Grant”
Exoplanet hunter and S&T author Sara Seager is among 24 scientists and artists granted one of 2013’s prestigious MacArthur Fellowships, commonly known as the “genius grant.”
Comet ISON to Fly By Mars
On October 1st, Comet ISON will pass closer to Mars than it ever will to Earth. The Red Planet’s rovers and orbiters are ready to send home postcards of the event.
New 3D Maps of Milky Way's Bulge
New 3D maps of the Milky Way's central bulge of stars show a distinctively peanut-like shape. The maps give clues about how our galaxy evolved to its present-day form.
Glimpse Into Sun Befuddles Theorists
Scientists sneaked a peek into the Sun’s interior, but what they saw contradicts the assumptions made by models predicting solar activity.
17-Day ALMA Strike Ends in Resolution
The 17-day strike at the world’s largest ground-based observatory ended Saturday, and ALMA's revolutionary observations of the millimeter/submillimeter sky restart today.
Green Bank Telescope's $1,000,000 Boost
Threatened by NSF cuts, the Green Bank Telescope signed a deal with West Virginia University to receive $1 million over the next two years. But the radio antenna will need more than that to survive long-term.
Source Found for Magellanic Stream
New observations solve the origins of a long rivulet of gas encircling the Milky Way.
New Pulsar Explores Heart of Milky Way
A pulsar discovered last April is helping astronomers measure the magnetic field surrounding our galaxy’s central black hole.
How ALMA Works Its Magic
ALMA (ESO/NAOJ/NRAO) / C. Malin In the November 2013 issue of S&T, I write about a revolutionary new telescope being built in the Chilean Atacama Desert. The Atacama Large Millimiter/submillimeter Array (ALMA) explores a little-known region of the electromagnetic spectrum, waves that are longer than the farthest infrared but shorter…
Curiosity's Views of Gale Crater
Since its arrival in August 2012, NASA's newest robotic rover has been taking snapshots of the flat Martian plain on which it landed and the tantalizing topography that looms in the distance.