Following the Yellow Brick Road to Mercury
Close to the Sun within 28 degrees, the fastest and second smallest planet in our solar system is Mercury. Images have been taken from the NAC, or Narrow Angle Camera, which is part of the Mercury Dual Imaging System (MDIS), with the Messenger mission clock counting its mission time at 1330 days, 06 hours, 29 minutes, and 02 seconds at this writing.
In NASA’s early strategy of its Solar System exploration, they described the Mercury fly-by as similar to “pointing your spacecraft in the right direction to pass by the planet as it orbits the Sun, and get whatever you can during the high-speed rendezvous.” And it worked. But then comes a situation called “orbital insertion”, with a count of 1087 days, 19 hours, 45 minutes, and 52 seconds at this moment until March 18, 2011.
Recently, on January 14, 2008, Mercury received its first fly-by from NASA’s Messenger, reaching out to approximately 124 miles above Mercury’s surface. Quickly taking a picture of Messenger’s fast approach by the NAC about 470,000 from Mercury, it has been seen that the surface of Mercury is mysteriously wrinkled with mysterious chains of cliffs and peppered with impact craters.
A previous theory regarding Mercury has been recently changed by Scott King, a planetary geophysicist at Virginia Tech University. The old theory by scientists thought that a two-mile long group of “lobate scarp” cliffs were actually created as the crust of Mercury bunched up around a shrinking interior. But King’s new theory is suggesting that rising sheets of hot mantle rock popped out of the planet’s characteristic ridges, forming the Martian cliffs that were created. “There’s a preferred north-south alignment to these scarps,” Scott King, a planetary geophysicist at Virginia Tech University, told SPACE.com. “If you just have a shrinking sphere, there’s no reason they should be aligned. It should be fairly random.”
The King theory is in his detailed computer-modeled hypothesis in the March 16, 2008 issue of “Nature Geoscience.” This article reveals his thoughts on linear sheets of rock heaving from beneath the Mercury crust. “It’s a very plausible idea,” said Sean Solomon, principal investigator for NASA’s MESSENGER spacecraft at the Carnegie Institution of Washington, who was not involved in the study. “It gives a nice set of predictions about what we might see, so it’s highly testable.”
This entry was posted on Friday, March 21st, 2008 at 12:23 pm and is filed under Space Agency News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
