Congratulations to Bird of the Wind, Archimedes, and all you Space Bloggers who have figured out that Destination One is indeed Earth’s little sister, the planet closest to the sun. I’m sure you also realize that the mysterious ‘messenger from Earth’ is actually NASA’s probe MESSENGER, that just 13 days ago became the first spacecraft ever to enter into orbit around Mercury. It took 6.5 years, 4.9 billion miles, and more than 15 trips around the sun to make this happen. Why was it so hard? Two words: gravity well.
Mercury is so close to the sun that in order to counteract its tremendous gravitational pull, the planet must zoom through space at an incredible 106,000 mph. For a spacecraft to stand a chance of entering Mercury’s orbit, it has to match that speed. Like a baseball leaving a pitcher’s glove, Messenger swung around Mercury and Venus numerous times, using the planets’ gravity to propel it ever faster and closer to Mercury’s path. Finally, just thirteen days ago, Messenger successfully managed the very tricky maneuvers necessary to slip into orbit around the fleeting planet. See how NASA herself describes this historic feat: Finally! NASA Prepares to Orbit Mercury
But now that it is finally in orbit, NASA’s space traveler faces another tough problem. As you can imagine, being the closest planet to the sun, Mercury is HOT! To find out how NASA plans to keep it cool, check out Messenger’s special design.
Stop back tomorrow as we wrap up our trip to Mercury and prepare to take off for Destination Two!