Scratching the Dunes
Opportunity's mission scientists have eyed the dunes in the deep pit known as Endurance crater. The sandy terrain has deterred the rover from going further, at the risk of getting trapped.

Odyssey's New Odometer
One Mars orbiter, Odyssey, has mapped the red planet for hydrogen while also serving as a communications relay link to surface rovers in the first interplanetary satellite constellation.

Finding Super-Earths
Of the more than 120 extrasolar planets found so far, most are as large or larger than our own Jupiter. Finding rocky worlds like Earth is nearly at the limit of current technology, but the European Southern Observatory in Chile reports finding the smallest super-Earth yet.

Piggybacking DNA
The DNA molecule's prolific capacity to multiply has been employed by Harvard biochemists to template new libraries of organic reactions. Retooling this central molecule as a carrier offers a chance to explore new branches of how biochemistry might work--or might once have worked in the past.

Citizen of the Solar System
NASA's David Morrison won the 2004 Carl Sagan medal from the Division for Planetary Sciences. He talked with Astrobiology Magazine about the risks and rewards of extending science beyond our biosphere.

Meteorites Donated Life's Phosphorus
Phosphorus is much rarer in nature than are hydrogen, oxygen, carbon, and nitrogen, but just as critical to life. Where the phosphorus came from has been a mystery, but one recent hypothesis maintains that meteorites might be a source of Earth's early phosphorus.

Beagle 2: Lessons Learned
The ambitious Mars lander, Beagle 2, never was able to respond from the surface back to Earth, but the mission team has assembled their thoughts on making the next one better.

Backyard Telescopes for New Planets
Could a new world be discovered with a department store telescope having only a small 4-inch diameter lens? It was a little more than a decade ago that the world's most powerful telescopes could just begin to discover extrasolar planets, but with over 120 new worlds found, the technique seems primed to become general.

Shepherding the Lightweight World
More spectacular Saturn images from Cassini have arrived, but a two-dimensional view of this ringed world cannot capture its strange composition as the only planet less dense than water.

Martian Basin Dune
Among the forces that reshape Mars, few play as prominent a role as the combined effects of impacts and wind. In unison, the result is a reshaped landscape where great craters host equally spectacular dunes.