Mercury mystery
The first rock from the Sun is Mercury.
Temperatures on Mercury range from a perishing
-168°C to a baking 427°C. The Mariner 10 mission mapped around half of the planet's surface in the 1970s, but the other half is still a mystery. It's too close to the Sun for the Hubble Space Telescope to be able to take images safely.
NASA's Messenger spacecraft is due to launch in July 2004 and should reach Mercury in 2011. Europe's planning an investigation called BepiColombo, set to launch in 2012.
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ESA's proposed BepiColombo mission to Mercury
Image: ESA |
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