Look out below! NASA’s MESSENGER spacecraft is at its lowest altitude of any spacecraft above Mercury, and over the next couple of months it’s going to get even lower above the planet.
The spacecraft — whose name stands for MErcury Surface, Space ENvironment, GEochemistry, and Ranging — is doing a close shave above the sun’s closest planet to look at the polar ice and its gravity and magnetic fields.
“This dip in altitude is allowing us to see Mercury up close and personal for the first time,” stated Ralph McNutt, the project scientist for MESSENGER at the Johns Hopkins University Applied Physics Laboratory (APL).
MESSENGER is the first-ever mission to orbit Mercury. It arrived at the planet in March 2011 and has now spent three Earth years or 14 Mercury years examining the cratered planet and its environment. The campaign has revealed many secrets about Mercury, ranging from the discovery of ice deposits to changes in its tenuous atmosphere due to the Sun.
The spacecraft made its lowest approach above the planet on July 25, at 62 miles (100 kilometers) and will keep moving lower due to “progressive changes” in its orbit, APL stated. By Aug. 19, the minimum altitude will be 50 km (31 miles), and then the closet approach will be on Sept. 12 at 25 km (16 miles).
After that, the team will temporarily raise the spacecraft’s orbit again before it makes a planned impact on the planet’s surface in March 2015. The NASA mission is operated and managed by Johns Hopkins University.
“…and then the closet approach will be on Sept. 12 at 25 km (16 miles).”
Sounds like this last approach was meant to be kept a secret.