NASA Makes History

According to a NASA press release, on January 14, 2008, a NASA spacecraft will get up close and personal with the planet Mercury. The NASA spacecraft will soar over the planet for the first time in almost 33 years. The historic flyby will provide NASA with new images of Mercury and could open up new theories in the study of the solar system.

During its 4.9-billion mile journey, the spacecraft MESSENGER will use the pull of Mercury's gravity to guide it closer to the planet's orbit. The MESSENGER, launched August, 2004, has already flown twice past the Earth and Venus.

The NASA spacecraft's name, MESSENGER, stems from these roots: MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft = MESSENGER.

NASA is especially interested in an impact crater, called Caloris. The Caloris basin is an impact crater about 800 miles in diameter, making it one of the largest impact basins in the solar system.

Louise Prockter, the instrument scientist for the Mercury Dual Imaging System at the Johns Hopkins University Applied Physics Laboratory in Laurel, is quoted as follows: "Caloris is huge, about a quarter of the diameter of Mercury, with rings of mountains within it that are up to two miles high. Mariner 10 saw a little less than half of the basin. During this first flyby, we will image the other side."

NASA hopes that the encounter will bring better results than the latest mission to Mercury with the spacecraft Mariner 10. Mariner 10 flew by Mercury in 1970, but it only surveyed only one hemisphere.

Sean C. Solomon, MESSENGER principal investigator, Carnegie Institution of Washington is quoted as follows: "During this flyby we will begin to image the hemisphere that has never been seen by a spacecraft and Mercury at resolutions better than those acquired by Mariner 10. Images will be in a number of different color filters so that we can start to get an idea of the composition of the surface."

Of special interest are measurements of the mineralogical and chemical composition of Mercury's surface. NASA seeks to gather more knowledge about Mercury's gravity field, the global magnetic field, the size of Mercury's core, and the energetic particle and plasma of Mercury's magnetosphere.

Alan Stern, associate administrator for NASA's Science Mission Directorate, Washington, is quoted as follows: "This is raw scientific exploration and the suspense is building by the day. What will MESSENGER see? Monday will tell the tale."