Cassini tagged posts

This artist’s rendering shows Cassini as the spacecraft makes one of its final five dives through Saturn’s upper atmosphere in August and September 2017. Credit: NASA/JPL-Caltech

NASA’s Cassini spacecraft will enter new territory in its final mission phase, the Grand Finale, as it prepares to embark on a set of ultra-close passes through Saturn’s upper atmosphere with its final five orbits around the planet.

Cassini will make the first of these five passes over Saturn at 12:22 a.m. EDT Monday, Aug. 14. The spacecraft’s point of closest approach to Saturn during these passes will be between about 1,010 and 1,060 miles (1,630 and 1,710 kilometers) above Saturn’s cloud tops.

The spacecraft is expected to encounter atmosphere dense enough to require the use of its small rocket thrusters to mai...

This collage of images from NASA’s Cassini spacecraft shows Saturn’s northern hemisphere and rings as viewed with four different spectral filters. Credit: NASA/JPL-Caltech/Space Science Institute

Scenes include Saturn’s hexagon-shaped jet stream. NASA’s Cassini spacecraft has sent to Earth its first views of Saturn’s atmosphere since beginning the latest phase of its mission. The new images show scenes from high above Saturn’s northern hemisphere. Cassini began its new mission phase, called its Ring-Grazing Orbits, on Nov. 30. Each of these weeklong orbits – 20 in all – carries the spacecraft high above Saturn’s northern hemisphere before sending it skimming past the outer edges of the planet’s main rings.

Cassini’s imaging cameras acquired these latest views on Dec...

This graphic shows the closest approaches of Cassini’s final two orbital phases. Ring-grazing orbits are shown in gray (at left); Grand Finale orbits are shown in blue. The orange line shows the spacecraft’s Sept. 2017 final plunge into Saturn. Image credit: NASA/JPL-Caltech

NASA’s Saturn-orbiting Cassini spacecraft has made its first close dive past the outer edges of Saturn’s rings since beginning its penultimate mission phase on Nov. 30. Cassini crossed through the plane of Saturn’s rings on Dec. 4 at 5:09 a.m. PST at a distance of ~57,000 miles above Saturn’s cloud tops. This is the approximate location of a faint, dusty ring produced by the planet’s small moons Janus and Epimetheus, and just 6,800 miles from the center of Saturn’s F ring.

About an hour prior to the ring-plane crossing...

Sunlight glints off of Titan’s northern seas this near-infrared, color mosaic from NASA’s Cassini spacecraft. Credit: NASA/JPL/Univ. Arizona/Univ. Idaho

A new study finds that a large sea on Saturn’s moon Titan is composed mostly of pure liquid methane, independently confirming an earlier result. The seabed may be covered in a sludge of carbon- and nitrogen-rich material, and its shores may be surrounded by wetlands. Of the hundreds of moons in our solar system, Titan is the only one with a dense atmosphere and large liquid reservoirs on its surface, making it in some ways more like a terrestrial planet.

Both Earth and Titan have nitrogen-dominated atmospheres — over 95% nitrogen in Titan’s case...