Paul Rincon, BBC science reporter, has been busy in Houston at the 2007 Lunar and Planetary Science Conference (LPSC).

Yesterday he posted a story about what appears to be a 5.5-km wide, newly discovered space impact crater under the Central Valley in California.

Data from a 3D seismic survey of an ancient sea bed clearly shows a circular structure buried 1,490-1,600m (4,890-4,250ft) below sea level.

The Victoria Island structure, as it has been named, has a concentric rim surrounding a “central uplift” – a peak at the centre – which are both characteristic of impact craters.

Today, Rincon had another story from the conference about some possible caves found on Mars by NASA’s Odyssey spacecraft.

The candidate caves are on the flanks of the Arsia Mons volcano and are of sufficient depth their floors mostly cannot be seen through the opening.

What’s most interesting is the potential for these providing a haven for life.

The caves may be the only natural structures capable of protecting primitive life forms from micrometeoroids, UV radiation, solar flares and high energy particles that bombard the planet’s surface.

Sounds like a cool conference. :)