Posts Tagged: Sean Hsu

In its final days, Cassini bathed in “ring rain”

On its last orbits in 2017, the long-running Cassini spacecraft dove between Saturn’s rings and its upper atmosphere and bathed in a downpour of dust that astronomers call “ring rain.”

In research published today in Science, LASP research associate Hsiang-Wen (Sean) Hsu and his colleagues report that they successfully collected microscopic material streaming from the planet’s rings.

The findings, which were made with Cassini’s Cosmic Dust Analyzer and Radio and Plasma Wave Science instruments, come a little more than a year after the spacecraft burned up in Saturn’s atmosphere. They stem from the mission’s “grand finale,” in which Cassini completed a series of risky maneuvers to zip under the planet’s rings at speeds of 75,000 miles per hour.

Complex organics bubble from the depths of Enceladus

New data collected from the Cassini spacecraft have revealed complex organic molecules originating from Saturn’s icy moon Enceladus, strengthening the idea that this ocean world hosts conditions suitable for life.

LASP research scientists Sascha Kempf and Sean Hsu co-authored a new study, published in Nature, based on the data.

Very little was known about Enceladus prior to 2005—the year when Cassini first flew by. Since then, it has become a continuous source of surprises, with secrets still being revealed even now, after the end of the mission.

Cassini Spacecraft Samples Interstellar Dust

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.

PRESS RELEASE: Saturn Moon’s Ocean May Have Hydrothermal Activity

Scientists with NASA’s Cassini mission, led by LASP and University of Colorado postdoctoral researcher, Sean Hsu, have found that microscopic grains of rock detected near Saturn imply hydrothermal activity is taking place within the moon Enceladus.

This is the first clear indication of an icy moon having hydrothermal activity—in which seawater infiltrates and reacts with a rocky crust, emerging as a heated, mineral-laden solution. The finding adds to the tantalizing possibility that Enceladus, which displays remarkable geologic activity including geysers, could contain environments suitable for living organisms.

The results were published today in the journal Nature.

LASP scientist successfully models Saturn dust streams

Using data from the NASA Cassini mission, a team of scientists led by LASP researcher Sean Hsu, has successfully modeled dust streams being expelled from Saturn at speeds of more than 62 miles (100 km) per second. The data, taken from the Cosmic Dust Analyzer (CDA) and the magnetometer on board Cassini, provide new information about the sources of the dust, as well as interactions within the mix of subatomic particles in which the charged dust is immersed, called dusty plasma.