Mercury!

Yesterday the Messenger spacecraft made its second fly-by of the planet Mercury, and early this morning it started returning science data from the encounter – including the three photos shown here.

This is another of NASA's robotic explorers that's doing incredible science at a bargain-basement price (especially compared to the International Space Station).

NASA's press release starts:

MESSENGER Reveals Mercury as Never Seen Before

When Mariner 10 flew past Mercury three times in 1974 and 1975, the probe imaged less than half the planet. In January, during MESSENGER’s first flyby, its cameras returned images of about 20 percent of the planet’s surface missed by Mariner 10. Yesterday, at 4:40 am EDT, MESSENGER successfully completed its second flyby of Mercury, and its cameras captured more than 1,200 high-resolution and color images of the planet – unveiling another 30 percent of Mercury’s surface that had never before been seen by spacecraft.

“The MESSENGER team is extremely pleased by the superb performance of the spacecraft and the payload,” said MESSENGER Principal Investigator Sean Solomon of the Carnegie Institution of Washington. “We are now on the correct trajectory for eventual insertion into orbit around Mercury, and all of our instruments returned data as planned from the side of the planet opposite to the one we viewed during our first flyby. When these data have been digested and compared, we will have a global perspective of Mercury for the first time.”

I'd say they sound a little excited. As well they should be.

As usual, click on any of the photos for a larger view...