NASA’s Cassini spacecraft today begins the first of three close encounters with Saturn’s moon Enceladus with images expected within the next couple of days. The first pass will focus on the north polar region of the satellite.
Cassini, which will pass at an altitude of 1,839 kilometre above the moon’s surface at 10:41 a.m. UTC.
The spacecraft’s final two approaches will take place in late October and mid-December.
When Cassini last approached Enceladus the north of the moon was shrouded in darkness during its winter. Now that it is summer there, the Sun is shining on the high northern latitudes.
NASA explains what it will be looking for:
“…signs of ancient geological activity similar to the geyser-spouting, tiger-stripe fractures in the moon’s south polar region. Features observed during the flyby could help them understand whether the north also was geologically active at some time in the past.”
“We’ve been following a trail of clues on Enceladus for 10 years now,” said Bonnie Buratti, a Cassini science team member and icy moons expert at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.
“The amount of activity on and beneath this moon’s surface has been a huge surprise to us. We’re still trying to figure out what its history has been, and how it came to be this way.”