Nasa has released a new video taken by the Cassini spacecraft showing the view as it swooped over Saturn in its first plunge inside the planet's rings late last month.
One of Cassini's imaging cameras took a series of rapid-fire images as the spacecraft also captured the closest-ever images of the Saturn on April 26 during its first plunge through the planet's ring plane.
Now in its final laps around Saturn after observing it for 13 years, Cassini dove through the narrow gap between the planet and its innermost ring, where no spacecraft has ever gone before. It was the first of 22 planned close encounters to bring the robotic probe into unexplored territory between Saturn's cloud tops and its rings.
The movie shows an hour worth of observations as the spacecraft moved southward over Saturn. It begins with a view of the swirling vortex at the planet's north pole, then heads past the outer boundary of the hexagon-shaped jet stream and continues southward.
During the hour, the spacecraft's altitude above the clouds dropped from 45,000 to 4,200 miles (72,400 to 6,700 kilometres).
"I was surprised to see so many sharp edges along the hexagon's outer boundary and the eye-wall of the polar vortex," said Kunio Sayanagi, an associate of the Cassini imaging team based at Hampton University in Virginia, who helped produce the new movie. "Something must be keeping different latitudes from mixing to maintain those edges," he said.
Toward the end of the sequence, the camera frame rotates as the spacecraft reorients to point its communication antenna, used as a shield as Cassini crossed the planet's ring plane, in the direction of the spacecraft's motion.
"The images from the first pass were great, but we were conservative with the camera settings. We plan to make updates to our observations for a similar opportunity on June 28 that we think will result in even better views," said Andrew Ingersoll, a member of the Cassini imaging team based at California's Caltech.
Cassini is travelling through the gap at a relative speed of about some 77,000 mph (124,000 kph) so even small particles striking the spacecraft can be deadly.
Cassini has been probing Saturn, the sixth planet from the sun, and its entourage of 62 known moons since July 2004, but is running low on fuel.
Nasa plans to crash the spacecraft into Saturn on its last dive, scheduled for September 15, to avoid any chance Cassini could someday collide with any ocean-bearing moons that have the potential to support indigenous microbial life.
From The Telegraph
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