Right now, the Cassini Spacecraft is flying around the planet Saturn sending data back to scientists all over the world. One of the scientists working on the Cassini Solstice Mission is University of Montana professor of physics and astronomy Daniel Reisenfeld, whose work has helped solve a astrophysical conundrum.

"Early on in the mission we discovered that the magnetosphere of Saturn, which is the region in space around Saturn that is filled with plasma or ionized gas, most of the composition of that magnetosphere is actually water ions from a moon of Saturn called Enceladus," Reisenfeld said.

Scientists wanted to know why the water was in the magnetosphere and where it was going. An instrument developed here in Montana helped them find an answer.

"There is an instrument on board Cassini which analyzes the composition of the plasma, and I have developed the technique for taking the raw data that the instrument collects, interpreting it and actually detecting the water ions," Reisenfeld said. "Most of the technique was developed her, at the University of Montana."

It turns out, the water ions were trapped by two different magnetospheres with an exit point that had been hidden behind the planet. Reisenfeld and other scientists hope this discovery will lead to a better understanding of other fast spinning objects like Jupiter and quasars.