LASP planetary scientist Larry Esposito has been eying the fabulous rings of Saturn for much of his career, beginning as a team scientist on NASA’s Pioneer 11 mission when he discovered the planet’s faint F ring in 1979.
He followed that up with observations of Jupiter’s and Saturn’s rings from the Voyager and Galileo spacecraft, which carried instruments designed and built at LASP. Now, as the principal investigator for the Ultraviolet Imaging Spectrograph (UVIS) on the Cassini-Huygens mission to Saturn, Esposito and his Cassini colleagues are feeling a bit somber as the mission nears its end. The spacecraft has run out of fuel and will disintegrate in Saturn’s dense atmosphere early on the morning of Sept. 15.
In 1977, two NASA space probes destined to forever upend our view of the solar system launched from Cape Canaveral, Florida.
The identical spacecraft, Voyager 1 and Voyager 2, took off in in August and September 40 years ago and were programmed to pass by Jupiter and Saturn on different paths. Voyager 2 went on to visit Uranus and Neptune, completing NASA’s “Grand Tour of the Solar System,” perhaps the most exhilarating interplanetary mission ever flown.
CU Boulder scientists at LASP, who designed and built identical instruments for Voyager 1 and Voyager 2, were as stunned as anyone when the spacecraft began sending back data to Earth.
Toting an ultraviolet instrument designed and built by LASP, NASA’s Cassini spacecraft made the first of 22 dives between the rings of Saturn and the gaseous planet today, the beginning of the end for one of NASA’s most successful missions ever.
Launched in 1997 and pulling up at Saturn in 2004 for the first of hundreds of orbits through the Jovian system, the Cassini-Huygens mission has fostered scores of dazzling discoveries. These include in-depth studies that date and even weigh the astonishing rings; the discovery of methane lakes on the icy moon Titan; hot water plumes found squirting from the moon Enceladus; and closeup views of the bright auroras at the planet’s poles.
Planetary scientists are a step closer to understanding changes in the puzzling jets of gas and dust grains observed shooting into space from cracks on the icy surface of Enceladus, a moon of Saturn.
First observed in 2005 by NASA’s Cassini spacecraft as it orbited the ringed planet, the plume is coming from a subterranean, salty ocean beneath the moon’s surface. The latest observations with NASA’s Cassini spacecraft now at Saturn by a team including Larry Esposito, LASP planetary scientist and University of Colorado Boulder professor, indicate at least some of the narrow jets there blast with increased fury when the moon is farther from Saturn.
NASA’s Cassini spacecraft has detected the faint but distinct signature of dust coming from beyond our solar system. The research, led by a team that includes scientists at the University of Colorado and LASP, will be published in the journal Science on Friday, April 15, 2016.
Cassini has been in orbit around Saturn since 2004, studying the giant planet, its rings, and its moons. The spacecraft has also sampled millions of ice-rich dust grains with its Cosmic Dust Analyzer (CDA) instrument. LASP research scientists Sascha Kempf, Sean Hsu, and Eberhard Grün are all co-investigators for the Cassini CDA instrument and co-authors of the paper.
In 1977, Jimmy Carter was sworn in as president, Elvis died, Virginia park ranger Roy Sullivan was hit by lightning a record seventh time and two NASA space probes destined to turn planetary science on its head launched from Cape Canaveral, Fla. The identical spacecraft, Voyager 1 and Voyager 2, were launched in the summer and programmed to pass by Jupiter and Saturn on different paths. Voyager 2 went on to visit Uranus and Neptune, completing the “Grand Tour of the Solar System,” perhaps the most exciting interplanetary mission ever flown. University of Colorado Boulder scientists, who designed and built identical instruments for Voyager 1 and Voyager 2, were as stunned as anyone when the spacecraft began sending back data to Earth.
A study published in the journal Nature and co-authored by LASP scientist Sascha Kempf indicates that samples of water vapor and ice particles coming from Saturn’s icy moon Enceladus demonstrate evidence for a large, subterranean salt-water reservoir. The Cosmic Dust Analyzer (CDA) on board the NASA Cassini spacecraft measured the composition of plumes—emanating from fractures called tiger stripes—and found that ice grains close to the moon are salt rich, unlike those that make up the planet’s E Ring.