ANN ARBOR—The MESSENGER spacecraft, which involved some 75 University of Michigan engineers, scientists and students, is expected to crash into the planet Mercury this Thursday afternoon (April 30). This is how NASA intended the mission to end.
We asked Jim Raines, U-M research scientist and MESSENGER team member, to help quantify the crash. He worked with others on the MESSENGER team to put it in perspective.
- Meteors with the same mass as MESSENGER (513 kg) slam into Mercury about every month or two, and typically with 10 times the speed and 100 times the energy. The planet doesn't have a thick atmosphere that would slow down objects headed for the surface.
- The 1,131-pound spacecraft will hit with the energy of about a ton of TNT, or the force of a car traveling at about 2,000 mph.
- At almost 9,000 mph, the craft will be traveling three times faster than a speeding bullet and nearly 12 times the speed of sound.
- On MESSENGER's last orbit, it will pass just 900-to-1,800 feet over the planet's surface. We have buildings that tall on Earth.
- The crater the craft will leave near Mercury's north pole is predicted to be about 50 feet wide. That's the width of an NBA basketball court.
- Nearly 55 percent of MESSENGER's weight at launch was fuel—which is about to run out.
- Related news story: Mercury mission nears epic mission end