Kill the Messenger!

Mercury Mission Set to End with Dramatic Crash

Quote:

April 28, 2015 |By Alexandra Witze and Nature magazine On April 30, after more than four years in orbit around Mercury, NASA's MESSENGER probe will plunge to its doom. Out of fuel and long past its intended one-year mission, the spacecraft will crash into the planet's surface at a speed of 3.9 kilometres a secon Mission head Sean Solomon, a planetary scientist and director of the Lamont-Doherty Earth Observatory in Palisades, New York, sat down with Nature to talk about what MESSENGER has accomplished since it launched in 2004. The following interview has been edited and condensed. Why did you want to send a mission to Mercury? Mercury was the last frontier of our knowledge about the inner Solar System. We had multiple missions to Mars and the Moon, and only Mariner 10 had gone to Mercury. It flew by three times [twice in 1974 and once in 1975], and its images gave us our first ideas about Mercury’s geological history. But there was so much unanswered. It was a planet that was really missing a lot of key information. What does it look like close up? Probably the most disappointing aspect of Mercury turned out to be how nearly uniform its colour was. The effects of space-weathering must be so strong, and so rapidly acquired, that there were no convincing mineralogical signatures. The hollows were a landform we didn't expect. They are bright depressions created by the loss of near-surface material. They are some of the youngest features on the planet, and speak to some sort of unstable material whose identity we are still working

Continues...

via International Skeptics Forum http://ift.tt/1OB32X8