For the first time in the history of astronomy, a probe has entered the orbit of the planet Mercury . The Messenger (acronym for the Mercury Surface, Space Environment, Geochemistry & Ranging mission), which started more than six and a half years ago and has traveled 7.9 million kilometers to reach its goal, will study the planet closest to the Sol. On March 23, its instruments will start up, and on April 4 it will begin its scientific mission.
The NASA probe will circle Mercury every twelve hours, and will carry out studies on the composition of the atmosphere and the surface of the planet. Scientists hope to obtain information about Mercury’s magnetic field and core , as well as determine if there is ice in the craters at its poles, which are permanently in shadow.
Maneuvers
Before getting into orbit, the spacecraft had to make a difficult maneuver that began at 8:45 p.m. Thursday (US East Coast Time) and concluded 15 minutes later. The most powerful 660-newton engine was fired to slow the spacecraft down so it could get into a highly elliptical orbit ranging from 200 kilometers to 15,000 kilometers. This large ellipse is necessary because the temperature on Mercury, the planet closest to the Sun, is very high and, although Messenger has a protective shield, it should be moved away to cool down and then closer to continue data capture. “Now is when the mission begins,” said Messenger’s chief scientist, Sean Solomon, after entering orbit. “We are ready to learn all about one of our closest neighbors.”
This is the first time that a spacecraft has been placed in the orbit of Mercury, one of the most difficult to investigate planets. And not only because it moves much faster than Earth and a spacecraft must travel at about 104,607 kilometers per hour to reach it, but also because it must face the heat of the Sun. Temperatures on this planet exceed 1,000 ºC.
After reaching the orbit of Mercury, NASA only has two planets left to orbit, Uranus and Neptune, although it has zoomed in on all of them with different missions.
