NASA has released a fetching composite colour snap of Mercury, captured by the Messenger spacecraft on its third and final fly-by of the planet prior to orbital insertion in 2011:

The agency explains that the photograph was obtained by Messenger's Wide Angle Camera using three separate images captured through 1000, 700, and 430 nanometre filters - "infrared, far red, and violet, respectively" ... "placed in the red, green, and blue channels, respectively".

Messenger has now imaged around 98 per cent of Mercury's surface. The missing areas lie at the poles, but they're expected to yield to the spacecraft's cameras when it enters permanent orbit.

NASA has also released a round-up of scientific findings based on the observations to date. These include analysis of Mercury's exosphere - and the "seasonal" effect on it depending on the planet's distance from the Sun - as well as new data on the make-up of its surface crust.

You can find more Mercury snaps here, Messenger tech details here and the main Messenger site here. ®

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