Six Days From Mercury and Counting!
8 Jan 2008
(Source: Johns Hopkins University Applied Physics Laboratory)
The MESSENGER spacecraft continues to approach Mercury and will be less than 3 million kilometers (1.9 million miles) away from the planet at the end of today. In just six days -- on January 14, 2008, at 2:04 p.m. EST -- the probe will pass a mere 200 kilometers (124 miles) above Mercury's surface. Extensive scientific observations are planned during this historic flyby, the first spacecraft flyby of Mercury in more than 30 years.
Mission operators at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., recently sent MESSENGER a series of commands to acquire nine sets of optical navigation images at the planet Mercury. "This technique was tested and validated after MESSENGER's second flyby of Venus in June 2007," explained MESSENGER Mission Operations Manager Andy Calloway. "The Mercury Dual Imaging System camera will be used to further refine knowledge of the spacecraft trajectory by taking a sequence of Mercury limb images that include known bright stars in the camera's field of view as the spacecraft approaches Mercury."
MESSENGER Principal Investigator Sean Solomon of the Carnegie Institution of Washington discussed the importance of the historic flyby during a Planetary Radio show aired on January 7. "I was a very junior assistant professor at MIT back when Mariner 10 flew by Mercury three times in 1974 and 1975," Dr. Solomon told host Mat Kaplan. "It made some important discoveries that raised some questions that have been with us for three decades. So to be returning to Mercury -- initially with this flyby but ultimately to go into orbit -- with a modern suite of instruments to answer those three-decade-old questions has all of us at the edge of our seats." The entire interview is available online at http://www.planetary.org/radio/show/00000270/.
To celebrate MESSENGER's first flyby of the planet Mercury, APL and the Planetary Society will host a public reception on the evening of the encounter. The event will be held in APL's Parsons Auditorium from 7:00 to 8:00 p.m. The featured speaker is Robert G. Strom, a professor emeritus of lunar and planetary studies at The University of Arizona. Strom was involved in the Mariner 10 mission, the first and only previous mission to Mercury, and he is now a member of the MESSENGER Science Team. He'll share his unique perspective on the significance of the MESSENGER mission. Find out more about Professor Strom through this previously featured story: http://messenger.jhuapl.edu/who_we_are/member_focus_062006.html. RSVPs for the public reception are being accepted at http://messenger.jhuapl.edu/RSVP/.
Anyone near a computer during MESSENGER's flyby encounter can watch the planned observations unfold with simulated views of Mercury as seen via MESSENGER's two cameras by accessing the Mercury Flyby Visualization Tool, available at http://messenger.jhuapl.edu/encounters/.
As the flyby continues to approach, additional information and features will be available online at http://messenger.jhuapl.edu/mer_flyby1.html. Following the flyby, be sure to check back frequently to see the latest released images and science results!
MESSENGER is about 37.7 million miles (60.6 million kilometers) from the Sun and 121 million miles (194 million kilometers) from Earth. At that distance, a signal from Earth takes 10 minutes and 47 seconds to reach the spacecraft.
MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) is a NASA-sponsored scientific investigation of the planet Mercury and the first space mission designed to orbit the planet closest to the Sun. The MESSENGER spacecraft launched on August 3, 2004, and after flybys of Earth, Venus, and Mercury will start a yearlong study of its target planet in March 2011. Dr. Sean C. Solomon, of the Carnegie Institution of Washington
, leads the mission as principal investigator. The Johns Hopkins University Applied Physics Laboratory
built and operates the MESSENGER spacecraft and manages this Discovery
-class mission for NASA