Texas students take TOPEX calibrations in Galveston Bay

Teams of high school and junior high students launched buoys into Galveston Bay, Texas, earlier this month to verify altimeter measurements from the JPL-managed TOPEX/ Poseidon satellite. The students' "float off" experiment will help oceanographers better understand ocean dynamics and calculate global sea level rise.

"What we are doing in Galveston Bay is a demonstration project to make students familiar with how we go about calibrating the TOPEX/Poseidon satellite," said Amy Neuenschwander of the University of Texas Center for Space Research, who coordinated the group's efforts with JPL's TOPEX/Poseidon outreach office.

Each team of students designed and built their own buoy, which was equipped with a Global Positioning System (GPS) receiver that helped the students precisely track its location. The buoys recorded sea level and wave height measurements along a track on the water as TOPEX/Poseidon flew overhead. This information will be used in conjunction with data from several tide gauges in the area to validate the satellite's performance.

The GPS is an array of 24 satellites that was originally developed by the U.S. Department of Defense. By measuring signals from these satellites, users can pinpoint their precise location almost anywhere on Earth.

"We are trying to get students interested in science early,"' Neuenschwander said. "When they can get a 'hands-on' project and see how it ties into real life and what real science and building something is all about, it really gets them turned on to science."

The idea seemed to be working. "This is probably the most fun- bringing the buoy down here and testing it and seeing it work with the satellite," said eighth-grader Rob Sawyer from Seabrook Intermediate School, Seabrook, Tex. "That's what I like the most."

"This is what I want to do later on in my life. Today, I'm getting a head start on learning how to use the equipment and what it is all about," said David Hull, an 11th grader at Boulder High School in Colorado.

In addition to the fun parts, the students' experiment is providing valuable data to the science team. "It's crucial that we have continuing calibration of the satellite's altimeter height measurements to help us determine if the global sea level is rising," said Dr. George Born, a TOPEX/Poseidon science team member at the University of Colorado, Boulder. "Locally, verifying the measurements of the sea level in Galveston Bay will prove useful in improving tide models by providing a reality check."

"Galveston Bay is an ideal site for us to conduct this experiment,"

Neuenschwander said. "As the TOPEX/Poseidon satellite passed directly over the center of the bay, there were numerous tide gauges to further verify the measurements and relatively low waves."

"This bay is Texas' most important coastal environment, containing natural resources which are self-renewing as long as the bay remains healthy and productive."

"Improved tide and circulation models will improve the ability to track pollutants such as oil spills in the bay as well as improving biological models," Born added. "Hence, the experiment has the long-term potential of contributing to the maintenance of a healthy ecosystem in the bay."

The "float-off" is part of an ongoing educational outreach program between JPL, The University of Texas Center for Space Research and the Texas Space Grant Consortium, in conjunction with the Colorado Center for Astrodynamics Research and the Colorado Space Grant Consortium. The Texas students are from two Houston-area high schools, Friendswood and Pearland, and one middle school, Seabrook Intermediate. The Colorado students are from Boulder High School and the University of Colorado.

Jet Propulsion Laboratory
Universe - May 31, 1996


Last Modified: Fri, Aug 20, 1998