Cassini–Huygens

Seeing Earth From Between Saturn’s Rings, Nearly a Billion Miles Away

Earth and the moon (on the left) from between Saturn's rings.
Earth and the moon (on the left) from between Saturn’s rings.

The Cassini Orbiter is about 5,000 pounds (minus its fuel, which is all gone, and the Huygens probe it dropped off on Titan in 2004) of science that’s been orbiting Saturn for nearly 13 years. It is, by any objective take, a vanishingly small speck in the vastness of space, and one of the subtle feats of its 12 sensors—including an ultraviolet imaging spectrograph, plasma spectrometer, and cosmic dust analyzer—is reminding…

In ‘grand finale,’ Cassini spacecraft sets off on collision course with Saturn

Cassini and Saturn
The Cassini spacecraft will explore the uncharted territory between Saturn and its rings (shown in this artist’s illustration) before plunging into the planet’s atmosphere in September.

DEEP DIVE

Cassini is bravely going where no spacecraft has gone before — between Saturn and its rings.

The probe, which launched in 1997 and has orbited Saturn since 2004, starts this daring expedition April 22. It will fly through the 2,400-kilometer-wide gap between Saturn and its rings 22 times before plunging into the planet’s atmosphere and burning up on Sept. 15.

Mission scientists designed this dramatic…

Bubbles may put mysterious fizz in Titan’s polar sea

Titan magic island
SHAPESHIFTER Nitrogen bubbles may be the source of an on-again, off-again bright spot, or “magic island,” on Saturn’s moon Titan. Cassini spacecraft images of the island, which sits in a hydrocarbon sea called Ligeia Mare, revealed the feature’s fickle nature.

Saturn’s main moon, Titan, has a “magic island,” which might be made of streams of nitrogen bubbles, scientists report April 18 in Nature Astronomy.

Images from NASA’s Cassini spacecraft show that the island, which appears as a bright spot,…

Food for microbes found on Enceladus

Enceladus’ plume
FINDING FOOD A deep dive into Enceladus’ plume, shown here in an artist’s illustration, reveals that the moon harbors molecular hydrogen. On Earth, the gas serves as a food source for some microbes, suggesting life could exist on Enceladus, too.

Saturn’s icy moon Enceladus packs snacks suitable for microbial life.

Data from the Cassini spacecraft show that the vaporous plume shooting out of the moon’s southern pole contains molecular hydrogen. It is probably generated when water in the moon’s subterranean ocean reacts with rock in its core, researchers report in the April 14 Science. Such reactions at hydrothermal vents and in other extreme environments on Earth produce high abundances of hydrogen, which some microbes use for food. There’s enough hydrogen on Enceladus to sustain microbial life, the team suggests.

“We are not saying Enceladus has life, but the discovery does move the moon higher on the list of potentially habitable places in the solar system,” says study coauthor J. Hunter Waite of the Southwest Research Institute in San Antonio.

Enceladus became a good target for finding life beyond Earth when researchers found a global ocean under the moon’s icy exterior and hints of hydrothermal activity (SN: 10/17/15, p. 8; SN: 4/18/15, p. 10)….

In new Cassini portraits, Saturn’s moon Pan looks like pasta

Pan in Cassini image
This week, Cassini captured the closest images ever taken of Pan, a small moon that orbits amid Saturn’s rings.

Saturn serves up the closest thing to space pasta, the latest round of images from NASA’s Cassini probe, released March 9, show.

On March 7, the spacecraft snapped a series of portraits of Pan, Saturn’s small moon that orbits within a 325-kilometer gap in one of the planet’s rings. Taken at a distance of 24,572 kilometers from the moon, these are the closest images of Pan to date.

The close-ups could help refine astronomers’ understanding of the mini moon’s geology and…