As a spacecraft nears a large celestial body, there is a point where the gravitational influence of that body becomes greater than that of any other body. Jupiter has a rather large gravitational influence, and the Juno spacecraft, still over a month away from its encounter with the giant planet, has crossed that threshold. From: JPL Press Release: 2016-136: Since its launch five years ago, there have been three forces tugging at NASA’s Juno spacecraft as it speeds through the solar system. The sun, Earth and Jupiter have all been influential — a gravitational trifecta of sorts. At times, Earth was close enough to be the frontrunner. More recently, the sun has had the most clout when it comes to Juno’s trajectory. Today, it can be reported that Jupiter is now in the gravitational driver’s seat, and the basketball court-sized spacecraft is not looking back. “Today the gravitational influence of Jupiter is neck and neck with that of the sun,” … Continue reading →