Mercury has been 'dynamic world' (BBC)

[eppur_se_muova]

By Paul Rincon
Science editor, BBC News website, The Woodlands, Texas

The planet Mercury was once an active and dynamic planet, according to new evidence from a Nasa spacecraft.

Data from the American Messenger probe shows that impact craters on the planet's surface were distorted by some geological process after they formed.

The findings, reported in Science magazine, challenge long-held views about the closest world to the Sun.

Another study looking at Mercury's gravity field shows that the planet has an unusual internal structure.

As well as being published in the journal Science, the research has also been presented here at the Lunar and Planetary Science Conference in The Woodlands, Texas.
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more: http://www.bbc.co.uk/news/science-environment-17248776

[ellisonz]

1. Interesting.

"People are making models of what 'super-Earths' could be like, and all these models are based on interiors of terrestrial planets as we know them," she said. "This gives people a broader range of things that need to be considered for planets around other suns."

http://www.latimes.com/news/science/la-sci-mercury-messenger-20120322,0,7068784.story

[dipsydoodle]

2. Mercury poles give up hints of water ice

A Nasa spacecraft has found further tantalising evidence for the existence of water ice at Mercury's poles.

Though surface temperatures can soar above 400C, some craters at Mercury's poles are permanently in shadow, turning them into so-called cold traps.

Previous work has revealed patches near Mercury's poles that strongly reflect radar - a characteristic of ice.

Now, the Messenger probe has shown that these "radar-bright" patches line up precisely with the shadowed craters.

http://www.bbc.co.uk/news/science-environment-17470151