Today at 1904 GMT, the NASA spacecraft Messenger will make its first approach of Mercury, the inner-most planet of our solar system. This evening’s approach is the first of three between now and 2011, designed to slow down the probe as it readies to begin orbiting the planet.

This will be the first visit to Mercury by any probe since 1975. More than 1,300 images of Mercury will taken during this encounter, so hopefully we can expect some great pictures to be released over the next couple of weeks.

If you want to read more about the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraf, then you can visit either the general NASA mission page or a more detailed page from the instrumentation team.

This mission is a very exciting one. Mercury remains one of the only planets to have not been fully mapped by probes (you may have seen the bald patch on many globes of the planet). There are a lot of people getting very excited today!