Mars

A tagalong to the Russian sample-return mission makes some researchers uncomfortable

It's the limited life span of batteries that keeps robots from being more widely available

Kepler's sensitivity to the orbit of a catalogued exoplanet bodes well for its ability to find Earth-like worlds

Also: updates on stem cells from proteins, quasicrystals and a billion-year memory drive

The European Space Agency today released this high-resolution stereo image taken by the Mars Express orbiter of a region southeast of Ma'adim Vallis , one of the largest canyons on Mars (after Valles Marineris ).

New research reveals a better way to boost happiness than counting blessings--imagining that the good things never happened

The only scientist and field geologist ever to visit the moon offers some pointers to those who will one day visit Mars

Deimos is the smaller of Mars's two tiny, asymmetrical moons at less than 10 miles across , and it orbits farther from the Red Planet (14,500 miles) than its larger counterpart Phobos does.

Signs of repeated ice- and snow-melt in a mid-latitude gully may point to the most recent water activity on the Red Planet's surface

Spare parts mean more weight, more expense and less science. What if the redundancy worked differently?

It might mean life, it might mean unusual geologic activity; whichever it is, the presence of methane in the atmospheres of Mars and Titan is one of the most tantalizing puzzles in our solar system

Localized gas plumes may point to biological or geologic activity