“Getting there was only half the fun,” says March 2011 issue of Scientific American. Because of Mercury’s proximity to the sun’s gravitational field, a direct flight to Mercury was not possible. The craft could not slow enough to be captured by Mercury’s atmosphere. To get to Mercury required one flyby of earth, two of Venus and three of Mercury itself. Each flyby slowed the craft so at the last pass it could be caught by Mercury’s gravity. The entire trip took 6 1/2 years.
Now that MESSENGER has arrived at its destination on March 23 the measuring instruments will be turned on and checked out, and the mission’s primary science phase will begin on April 4.
The primary science objectives of the mission include:
determine accurately the surface composition of Mercury
characterize the geological history of the planet
determine the precise strength of the magnetic field and its variation with position and altitude
investigate the presence of a liquid outer core by measuring Mercury’s libration
determine the nature of the radar reflective materials at Mercury’s poles
investigate the important volatile species and their sources and sinks on and near Mercury.
This astrologer wonders though just how well this will all work out since Mercury goes retrograde on March 28th.
For astrologers Mercury retrograde is a period where we advise our clients not to start new projects, sign important papers or buy large items. It certainly is a period where communication issues pop out of the blue and computer systems are unreliable.
The only way that we may hope that this mission goes off without a hitch is if the launch of Messenger was done during Mercury Retrograde, itself. But no such luck for MESSENGER. Below is the launch chart with date and time supplied by Wikipedia. It is probable that there will be problems with computer and communication systems.
Still, Mercury is expected to be on its mission for a year, so hopefully the MESSENGER team will recover critical functions to complete most of the mission.