Published: Dec. 5, 2004

Two experimental observation satellites built and controlled by undergraduate students at the University of Colorado at Boulder are set to be launched Friday, Dec. 10, for a brief study of clouds and testing of artificial intelligence.

The Three-Corner Sat mission, to be launched from Cape Canaveral, Fla., will obtain stereo images of changing environmental phenomena such as cloud formations, pollution plumes and sand or dust storms, according to Chris Koehler, director of the Colorado Space Grant College at CU-Boulder. The observations have practical applications, Koehler said.

"In theory, precise measurements of unstable cumulus cloud towers, for example, could cut down unnecessary commercial air traffic diversions," Koehler said. "These small satellites can collectively obtain three-dimensional data showing cloud thicknesses and altitudes inaccessible to conventional radar systems."

The satellites, nicknamed "Ralphie" and "Sparky" by organizers, each carry four digital cameras pointing in different directions. Artificial intelligence software developed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., will allow each satellite to make onboard decisions during the mission. The smart software, for example, can detect unexpected events and change the scheduling of satellite operations.

"We will take stereoscopic images using two different satellites to test the system's artificial intelligence software and stereo-image quality," said senior aerospace engineering major Ryan Olds, who is serving as mission operations team leader.

Three-Corner Sat is a joint effort of CU-Boulder, Arizona State University, New Mexico State University, NASA and the Air Force Office of Scientific Research. The project is being undertaken by students, primarily undergraduates, at the schools as part of the NASA-sponsored Space Grant Consortium program that began in 1989.

Approximately 120 CU-Boulder students have been involved in the Three-Corner Sat effort during the past four years, according to Koehler. "These students - who are mostly undergraduates -- are doing hands-on research, facing the same challenges as engineers

in industry or government," he said. "The experience they get at CU makes them extremely marketable graduates."

CU-Boulder students are responsible for mission control, science, the command and data-handling subsystem and the camera imaging subsystem. Arizona State students developed the structure and power subsystems and managed the overall project, and New Mexico State students built the communication subsystem.

The six-sided, 35-pound satellites are each about 18 inches across and 12 inches high. Released at roughly 135 miles above Earth, the satellites will slowly drift apart. Because of the very low-orbit altitude, the satellites will be in the outer edge of Earth's atmosphere. They are expected to be operational for only two to three days before atmospheric drag will cause them to start tumbling, fall into the atmosphere and burn up.

The mission has been altered and delayed from its original plan. Three satellites were built as part of the mission and were originally slated for launch aboard the space shuttle in 2003. After the shuttle Columbia tragedy in 2003, mission organizers pursued other means of launching the satellites and early in 2004 were offered an opportunity to be a part of the first launch of the new Boeing Delta IV Heavy rocket. Because of weight and space limitations, only two of the three satellites will be launched.

The new rocket was designed for launching large satellites into geosynchronous orbit. The Three-Corner satellites will be attached to the side of a test payload and will be released in a low Earth orbit before the second stage of the rocket is fired.

CU-Boulder students will control the satellites through a network of four ground stations connected by the Internet. Ground communication and tracking stations will be located at Arizona State, New Mexico State, the University of Puerto Rico and at a U.S. Navy base at Key West, Fla.

CU-Boulder's Space Grant Consortium students have designed, built and operated two space shuttle and three sounding rocket experiments. They are now finishing the Citizen Explorer Satellite, an educational spacecraft that will involve K-12 students from around the world, and working to complete an engineering unit of the DINO (Deployment and Intelligent Nanosatellite Operations) satellite, for competition for a launch as part of the University Nanosatellite III program.

More information about the Three Corner Satellite mission is available on the web at https://spacegrant.colorado.edu/tiki-index.php?page=3CS.