The Juno spacecraft will move past Earth (relatively) leisurely before it "slingshots" into space to take a good look at Jupiter.
"If you've ever whirled a ball attached to a string around your head and then let it go, you know the great speed that can be achieved through a slingshot maneuver," a University of Iowa press release reported. This is almost exactly what will happen to Juno as it begins its epic journey.
The craft will pass within 350 miles of the Earth's surface at exactly 3:21p.m. EDT Wednesday, Oct. 9, before moving on to the unknown.
"Juno will be really smoking as it passes Earth at a speed of about 25 miles per second relative to the sun. But it will need every bit of this speed to get to Jupiter for its July 4, 2016 capture into polar orbit about Jupiter. The first half of its journey has been simply to set up this gravity assist with Earth," Bill Kurth, University of Iowa research scientist and lead investigator for Juno's wave instrument, said in the news release.
"One of Juno's activities during the Earth flyby will be to make a movie of the Earth-moon system that will be the first to show Earth spinning on its axis from a distance," Scott Bolton, principal investigator for the Juno mission from Southwest Research Institute in San Antonio, said.
The craft will orbit the giant gaseous planet 33 times over the course of a year. It will be the first-ever craft to orbit over Jupiter's mysterious poles. Juno will hit the top of the planet's clouds and then move 1.75 every 11 days.
The researchers are especially excited to study Jupiter's stunning northern and southern lights.
"Jupiter has the largest and most energetic magnetosphere, and to finally get an opportunity to study the nature of its auroras and the role radio and plasma waves play in their generation makes Juno a really exciting mission for me," Kurth said.
Juno will also work to determine how much water and ammonia is present in Jupiter's atmosphere and map the planet's gravity and magnetic fields.
At the end of its mission, Juno will self-destruct by flying right into Jupiter's inhospitable atmosphere to ensure it does not contaminate the nearby moon Europa, where scientists wish to hunt for life in the future.
