Southwest Research Institute® (SwRI®) News

Printer Friendly Version

ALICE miniaturized ultraviolet spectrometer delivered for Rosetta comet mission launch

San Antonio, Texas -- July 18, 2001 -- Southwest Research Institute® (SwRI®) has successfully delivered the ALICE ultraviolet (UV) spectrometer to the European Space Agency (ESA) for integration aboard the ESA/NASA Rosetta comet orbiter spacecraft. Scheduled for launch in January 2003, Rosetta will use remote-sensing instruments to map and examine the surface of Comet Wirtanen in one of the most thorough investigations of a comet ever attempted. As it travels toward the comet, Rosetta will make flybys of the Earth-moon system, Mars, and two asteroids.

ALICE is the first in a new generation of UV spectrometers that weigh less and require far less power than previous instruments of their kind. Its development was triggered in the mid-1990s by NASA's push to miniaturize scientific instruments for future planetary missions. The shoebox-sized ALICE is one-third to one-half the mass of comparable UV spectrometers. After advanced laboratory development in support of Pluto mission concept studies, ALICE was proposed and selected for development on Rosetta by NASA and ESA in 1996. A more sophisticated version of ALICE has been proposed for NASA's hoped-for Pluto-Kuiper Belt mission.

"ALICE is a revolutionary instrument," says Dr. S. Alan Stern, director of the SwRI Space Studies Department in Boulder, Colorado. "It will reveal new insights into the origin, composition, and workings of comets - insights that cannot be obtained by either ground-based or earth-orbital observations." Stern serves as principal investigator of the ALICE instrument and its scientific investigation.

Developed at SwRI facilities in San Antonio, ALICE is one of the first instruments to be delivered for installation on Rosetta. The ALICE science team includes prominent cometary scientists from France, the University of Maryland, and Johns Hopkins University. Alenia Aerospace is assembling Rosetta - an ESA Cornerstone space science mission - in Turin, Italy.

ALICE is scheduled to be the first UV spectrometer to study a comet up close. "Although UV spectrometers in Earth orbit have studied comets for many years, ALICE will offer both unprecedented spatial resolution and unrivaled spectral sensitivity," says Stern.

The instrument features an advanced "micro-channel plate" detector, sophisticated optics, and a miniaturized 6,000-volt power supply, and operates on just 3 watts. "The Rosetta mission has to operate out to 5 AU (astronomical units), where the sun is only 4 percent as bright as it is here on Earth. That means that the each instrument must do their part to be very efficient," notes ALICE Project Manager John Scherrer, also of SwRI.

"Although ALICE is the first interplanetary UV spectrometer developed at SwRI, its development went smoothly, and its performance meets and even exceeds its original design specifications. It's going to be very exciting to see it returning data in flight," says Dr. James Burch, vice president of the SwRI Space Science and Engineering Division.

More information on the Rosetta mission is located at

For more information, contact Maria Stothoff, Communications, at (210) 522-3305.

SwRI News separate.gif (834 bytes) SwRI Home