SUNSET: 
A New Cycle is Dawning
It's nothing more than an inconspicuous blemish in the Sun's northern hemisphere, but a new sunspot has heralded the start of the next 11-year-long cycle of solar activity.
Cassini's Popularity Contest
After a month-long contest, the Cassini Imaging Central Laboratory for Operations (CICLOPS) has announced which images of Saturn are fan favorites.
Odds of Mars Strike Now 1-in-25
Astronomers have been watching a small asteroid that, they now say, has a 4% chance of colliding with Mars on January 30th.
Mars in the Crosshairs?
Astronomers are waiting to see what becomes of a skyscraper-size asteroid that has a 1-in-75 chance of hitting Mars in late January.
David Levy's Binary Asteroid
An otherwise run-of-the-mill, main-belt asteroid named 3673 Levy just got a lot more interesting: It has a tiny moon!
Tunguska's Blast: Less is More
Aided by high-def supercomputer simulations, two researchers now argue that small asteroids striking Earth — like what happened over Siberia in 1908 — may pose greater danger than previously believed.
Earth's Magnetosphere: On the Ropes
A constellation of five identical orbiting probes has detected skirmishes with the solar wind along Earth's magnetospheric front lines.
Deep Impact's New Assignments
Put to sleep after its smash success in 2005, one of NASA's interplanetary craft is getting a chance to search for extrasolar Earths and to visit a second comet.
Saturn's Sci-Fi Moons
Just when you thought you'd seen everything the ringed planet has to offer, the Cassini orbiter glimpses bizarre little moons shaped like flying saucers.
My Kind of Beauty Contest!
What's the most beautiful image taken by the Cassini spacecraft since it arrived at Saturn? Vote for your favorite today!
Lightning on Venus
The world next door seemed hellish enough with an atmosphere 90 times the sea-level pressure on Earth and surface temperature of 900°. Now, scientists say, there's lots of lightning — and what little water it has seems to be escaping to space.
Call for Images of Venus
Venus Express project scientists are inviting amateur and professional astronomers to contribute Earth-based images of the planet made at infrared, visible, and ultraviolet wavelengths.
Meteor Showers on Mars
Scientists now know what meteor showers occur in the rarefied atmosphere above Mars. So how come NASA's intrepid rovers can't see them?
Automated Lunar Impacts
NASA is watching the Moon to see how often it gets hit by meteoroids.
Pluto's New Family Portrait
Years of painstaking observation with some of the world's most powerful telescopes are finally showing us a glimpse of what awaits New Horizons when it reaches Pluto in 2015.
Titan's Frigid Shores
NASA's Cassini orbiter continues mapping Saturn's largest moon — and finding prime lakefront real estate.
Two Planets, One Discovery
Talk about serendipity! Two teams of scientists on opposite sides of the Atlantic, studying two planets on opposite sides of Earth, come up with the same quirky result.
Spotlight on New Horizons
Jupiter looks great through a backyard telescope, but can you imagine how much better it'd look from just 1.4 million miles away? NASA's Pluto-bound spacecraft got that chance last February.
Iapetus Yields Dark Secrets
Saturn's black-and-white moon has mystified astronomers for centuries. Finally, however, they're learning what a bizarre place it truly is.
Imaging Mercury
A team of astronomers have found new features on the innermost planet using an approach familiar to many amateur astronomers.
