Common bacteria found on spacecraft may be able to survive the harsh environs of Mars long enough to inadvertently contaminate Mars with terrestrial life.
The US military has apparently lost contact with an experimental hypersonic vehicle over the Pacific Ocean.
They say strangers are just friends you haven't met yet - but it's not a view Stephen Hawking shares. In a new documentary series for the Discovery channel, he suggests that we should be avoiding making contact with aliens at all costs.
The Hubble Space Telescope celebrates its 20th birthday today with the release of another photo that could come straight from the cover of a 1970s prog rock album.
The United States Air Force (USAF) is preparing to launch a top-secret robotic space plane from Cape Canaveral, Florida.
The new Solar Dynamics Observatory (SDO) could be as important to science as the Hubble Space Telescope, says NASA, as it releases its first close-up pictures of the sun.
The Venus Express spacecraft has completed an 'aerodrag' exercise, using its solar wings to catch and measure faint wisps of atmosphere just 180km above the planet.
Lunar explorers may have another hazard to contend with - new calculations by NASA's Lunar Science Institute team indicate that the moon's polar craters may be charged to hundreds of volts.
British scientists reckon they've identified the largest comet yet, using data from the ESA/NASA Ulysses spacecraft to measure the region of space disturbed by the its presence.
NASA is preparing to launch the first human-like robot to space as part of the Discovery STS-133 mission planned for September.
ESO astronomers have discovered nine new exoplanets - and found that several are going the wrong way.
A new radio astronomy facility has started mapping the universe at very low wavelengths and looking for messages from other civilisations.
If there really is life on saturn's moon Titan, it's likely to be smelly and explosive, according to astrobiologist William Bains.
NASA has announced its plans for the next few years. With the Constellation program for a manned moon landing axed, the focus will instead be on missions to the International Space Station and flight beyond Earth's orbit.
Venus is still capable of volcanic eruptions, data from ESA’s Venus Express spacecraft suggests.
ESA's Cryosat-2 ice mission is set for launch today, aiming to give scientists some hard evidence on the state of the world's ice caps.
More than 100 student teams from around the globe will this weekend take part in NASA's Great Moonbuggy Race.
Our entire universe may be located inside a wormhole, part of a black hole that lies within a much larger universe.
Astronomers have discovered a planet-like object circling a brown dwarf that appears to have formed much more quickly than was previously thought possible.
NASA has released the first Mars pictures commissioned by the public - and there's not a thumbprint or double exposure among them.