Cassini Spacecraft Begins Dramatic, ‘Ring-Grazing’ Orbits Today

Cassini’s 20 ring-grazing orbits (shown in tan) will final from late Nov until Apr 2017. Blue paint orbits that preceded a ring-grazing phase. Image: NASA/JPL-Caltech

NASA’s Cassini examine is impending a finish of a lifetime, and a little booster is going out with a bang. Today, a booster starts a array of 20 “ring-grazing” orbits, bringing Cassini a closest it’s ever been to Saturn’s vast, stately discs of ice and dust.


Since 2004, Cassini has been furloughed a gas hulk Saturn, a rings, and a many moons. The goal has suggested astonishing wonders, from geysers on Enceladus to flowing glass methane on Titan to a mysterious, color-changing hexagon during Saturn’s north pole. While NASA would substantially be happy if Cassini could keep buzzing around Saturn gnawing photos forever, a booster is using precariously low on fuel. One approach or another, a finish is approaching.

Next September, Cassini will make a self-murder thrust into Saturn’s atmosphere. But until then, a booster still has a lot of work to do.

From currently until Apr 22nd, Cassini will round over and underneath Saturn’s poles, in an elliptical circuit prone about 60 degrees from a ring plane. Once a week, it’ll swoop down to cranky that craft usually outward Saturn’s F ring, a slight rope that’s deliberate a outdoor border of categorical ring system.

Cassini will pass this unexplored ring corner a sum of 20 times, during a stretch of reduction than 5,000 miles (8,000 kilometers).


“We’re job this proviso of a goal Cassini’s Ring-Grazing Orbits, since we’ll be skimming past a outdoor corner of a rings,” Cassini plan scientist Linda Spilker pronounced in a statement. “In addition, we have dual instruments that can representation particles and gases as we cranky a ringplane, so in a clarity Cassini is also ‘grazing’ on a rings.”

Image: NASA/JPL-Caltech

During a ring-grazing orbits, Cassini will build adult a high-resolution image of a rings’ structures. While Saturn’s rings are thousands of miles wide, they are, astonishingly, reduction than mile thick. If we were holding a scale fondle indication of Saturn, those rings would be 100 times thinner than a piece of printer paper. Cassini will solve sum in these probably 2-D structures down to reduction than 0.6 miles (1 km) per pixel.



The subsequent 20 weeks will also means Cassini a event to snap a best photos nonetheless of 4 little Saturnian moons: Pandora, Atlas, Pan and Daphnis. Each of these moons is usually a few miles in diameter, too little to form a round figure underneath a possess gravity. Nevertheless, a moons’ little gravitational tugs figure and carve ring structure, and their combination might offer clues as to how a rings initial formed.

Atlas (left and core left) and Pan (center right and right) are dual of Saturn’s tiny, poorly-resolved satellites. Respectively, a moons Atlas and Pan measures 24 miles (39 km) and 20.5 miles (33 km) opposite during their equators. Image: NASA/JPL/SSI

After a ring-grazing orbits, Cassini’s report usually gets some-more action-packed. In April, a booster starts a swan song, a “Grand Finale” that brings it usually 1,000 miles (1600 km) above Saturn’s cloud tops and sends it on dizzying dives by a slight opening between a gas hulk and a rings. And on Sep 15th, Cassini will govern a final maneuver, plunging into Saturn’s atmosphere. The booster will ll bake adult and mangle apart, a molecules dispersing distant and far-reaching into a stormy round of gas that it’s spent a final decade-and-a-half studying.


Cassini is harnessing a gravitational flog from Titan to set it on a ring-grazing trail after today. During a initial F ring channel on Dec 4th, Cassini will make a nine-hour film of Saturn’s vigourous north pole, and snap a few income shots of a icy geysers during Enceladus’ south pole.

For anyone meddlesome in following a latest section in Cassini’s journey, NASA has a resources of information accessible online, including a full list of dates and times compared with any ring-grazing orbit, highlights of a opposite orbits, and detailed summaries of a scholarship in a weeks to come.


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