Mapping Starspots by Exoplanet Transits

Astronomers have detected individual starspots by watching exoplanets cross in front of them. New advances may enable extensive mapping of stars' spottedness by this technique, filling gaps left by other methods.

Solar System

Einstein's Gravity Protects Earth

Newton's laws of gravity have about a 60% chance of wreaking havoc in the inner solar system. Einstein's corrections lower these chances to about 1%.

Milky Way

Supernovae: Cosmic-Ray Superfactories

Now we know for sure. The cosmic-ray particles that bombard Earth from deep space originate in very exotic places: the shock waves in supernova remnants.


Planetary Preemies?

Protoplanetary disks around three young stars turn out to have large central holes, which were presumably cleared by still-growing Jupiter-mass planets. But there’s a problem: the stars are too young.


Black-Hole Missing Link Found?

Astronomers are searching galaxies with no central bulges for intermediate-mass black holes — the missing links between the small black holes that result from collapsing stars and the monsters in the cores of bulge galaxies. A team reports that it's found one — or maybe three.


A Now-You-See-It, Now-You-Don’t Quasar?

Poring over sky-survey data, a Dutch schoolteacher noticed a starless blue-green blob near a faint galaxy. Astronomers think "Hanny's Voorwerp" is a cloud of intergalactic gas lit by an active galactic nucleus (AGN) hidden in the galaxy just to its north. But if so, why don't we see the AGN?


Why You Missed the Supernova in M82

Radio astronomers have spotted emission from a supernova that went unnoticed when it exploded more than a year ago in the nearby galaxy M82.


Exoplanet Mapping Tested on Earth

Researchers are developing a method to detect oceans and clouds on planets orbiting other stars. To test this idea, they aimed the telescope aboard NASA’s Deep Impact probe toward Earth, and made a rough map of our world.

Stellar Science

How Did the Brown Dwarf Get Its Spots?

A binary pair of brown dwarfs, measured with high precision, seems to defy models of star formation — unless one of them is covered with starspots.


Dark Matter or Pulsars? Fermi is on the Case

Something funny is going on within a few hundred light-years of us, creating high-energy electrons that we don't understand. Recent data from NASA’s Fermi Gamma-ray Space Telescope keep the mystery alive.


Planck and Herschel to Probe Inflation and Starbirth

The Herschel Space Observatory and the Planck Surveyor, launched May 14th on a single Ariane 5 rocket, will peer deeply into dust clouds and map the microwave background.

Astronomy & Observing News

Experts Brainstorm Humanity’s Future

A lively conference near Harvard discussed interstellar travel, the search for life in the galaxy, the menace of various cataclysms, and humanity's control of its future evolution.

Hotheaded HD 80606b

Astronomy & Observing News

Longest-Period Transiting Exoplanet Yet

Valentine's Day this year brought a big surprise from 190 light-years away: the unlikely transit of an unusual planet.