SUNSET: 
A Solar-Cycle Climate Trigger
How can a change in the Sun's total brightness of just 0.01% alter weather patterns on Earth? Climate modelers think they've found the answer.
Were Asteroids Born Big?
Imagine if our solar system formed with an asteroid belt full of objects the size of Ceres — and no small stuff.
A Tropical Tempest on Titan
In April 2008, after months of cloud-free skies, a massive storm erupted in the dense atmosphere of Saturn's largest moon.
Apollo Landers Seen on the Moon
NASA's new Lunar Reconnaissance Orbiter has such a high-res camera that, at long last, it's possible to see the Apollo landers sitting on the Moon. You can even see the trails of astronauts' footprints! Browse the just-released pictures.
U.S. Meteorite Hunters Go Bicoastal
Two intense fireballs, one over Arizona and another three days later over the Maryland-Pennsylvania border, have triggered searches for fresh-fallen stones from interplanetary space.
Ulysses Gets a Final Farewell
Ground controllers have finally ended the 18½-year mission of a plucky probe that taught scientists virtually everything they now know about the Sun's polar regions.
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%.
A "Briny Deep" Inside Enceladus?
Planetary scientists are crazy about Saturn's most active moon but can't agree on what powers the towering plumes gas and particles erupting from near its south pole. New findings, published this week, hint that the water vapor might be slowly evaporating from a salt-laced ocean in deeply buried caverns.
Solar Sleuths Tackle the "Quiet Sun"
New insights, announced this week, help explain why solar activity has been in the doldrums for an unexpectedly long time.
Kaguya Mission Ends with a Flash
After circling the Moon for two years, the Japanese spacecraft Kaguya slammed into the lunar surface on June 10th — an event captured by an observatory in Australia.
Partial Lunar Eclipse Yields Key Finding
Who knew? A lunar eclipse is not just a pretty sky show. Just-published observations show that there's real science in the umbra's dim, ruddy light.
Why Are We Moving Away from the Sun?
A few years ago astronomers became aware that the Sun-Earth distance, the astronomical unit, is gradually growing larger. Now a team of Japanese theorists have looked to the tides for an explanation.
Auroras from "Space Tornadoes"
Another confusing piece of the puzzle has been added to the picture of how the Northern Lights work.
What's Going on Inside Enceladus?
One of Saturn's icy moons has a tummy ache, causing it to spew jets of gas and icy particles hundreds of miles into space. Researchers aren't sure of the cause — but they have some interesting guesses!
Craters Reveal Ice in the Martian Dust
High-resolution images from orbit reveal tiny craters — created within the past year — surrounded by splashes of water ice dredged up from just below the Martian surface.
Meteorites Found from Asteroid 2008 TC3
Last December a determined U.S. researcher traveled to Sudan to recover pieces of an asteroid that slammed into Earth's atmosphere only 19 hours after being spotted. It was a long shot that paid off beyond his wildest dreams.
Sculpting the Asteroid Belt
New simulations show that when the giant planets shifted their orbits 4 billion years ago, the asteroid belt became a wild and crazy place.
From Venus to Gaia… and back down to Earth
One of the many big differences between Earth and Venus that could have a bearing on habitability is the absence of a strong magnetic field on Venus. So is it just dumb luck that we have a magnetic field and Venus doesn’t? Or is something deeper going on here?
Saturn's Newest Moon is a Ringer
A tiny moonlet discovered around Saturn is the likely source of the planet's G ring.
Space Rock 2009 DD45 Buzzes Earth
Roughly 100 feet across, the tiny asteroid designated 2009 DD45 is about to get its 15 minutes of fame.
