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Today’s Mercury Flyby Is Brought to You by the Word “Intriguing”

At 4:40 EST today NASA’s MESSENGER space probe passed just 124 miles (200 kilometers) over the nearest planet to the sun.

The move marked the closest approach MESSENGER will make during its second Mercury flyby, part of its maneuvering to settle neatly into orbit in 2011.

The first flyby in January produced some amazing pictures and some darn neat science, as this mission has been steadily revealing parts of the planet that have never been seen before.


From the January images scientists were able to determine that Mercury has extensive volcanism and has been pummeled by meteorites. They also got a detailed look at an odd formation dubbed “the Spider” sitting in Caloris Basin.

In this latest swing past the planet, MESSENGER is meant to take steady observations for 20 hours after the closest approach. The craft won’t send its data back to Earth until collection is complete, leaving mission operatives to content themselves examining the “optical navigation” images taken as the probe neared the planet.

The last of these snapshots, taken about 14.5 hours before closest flyby, shows just a sunlit crescent at a resolution of about 4 miles (7 kilometers) per pixel.

—Image courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Although this is a far cry from the crisp, zoomed-in images the full flyby should produce, the introductory view does capture parts of the planet never before seen.

In an effort to make sense of it all, initial labels for features within the sliver of visible surface include “intriguing” dark and light materials, as well as “intriguing” ridges and scarps [it’s like Lt. Commander Data helps write the press releases].

There’s also a few smooth areas that the science team thinks could be more indicators of volcanic activity.

NatGeo News reporter Anne Minard has been keeping her sharp eye on the MESSENGER developments, so check the site later for more on the story.