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| Student-Tracked Atmospheric Research Satellite for Heuristic International Networking Equipment (STARSHINE) |
| Payload Bay |
| 353 lbs. |
| Principal Investigator: Professor R. Gilbert Moore, Utah State University |
| Overview |
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Twenty-five thousand students scattered across the United States and around the world are set to watch for their own twinkling satellite to sweep across the sky in the morning and evening twilight hours. The students polished nearly 900 aluminum mirrors that completely cover the beachball-sized satellite's outer surface. The spacecraft, which was designed and built by the Naval Research Laboratory in Washington, D.C., will be ejected from the space shuttle Discovery and placed in a circular orbit 220 miles above the Earth. As STARSHINE orbits the Earth this summer and into early winter, sunlight reflecting off its mirrors will be visible during twilight hours to observers on the ground as far north as central Canada and the northern tip of Scotland and as far south as the southern tip of South America, Africa and New Zealand. Teams of elementary, middle and high school students will visually track the satellite and note the times that it passes between selected pairs of targeted stars. The students will enter their observations on the STARSHINE project's Internet site at http://www.azinet.com/starshine, and NRL and the U.S. Space Command will use the measurements to calculate the satellite's orbit. The German Space Operations Center in Oberpfaffenhafen, Germany, will use the orbital data to issue sighting predictions so the students will know where and when to look for STARSHINE's next appearance over their observation sites. As the project progresses, high school students will be taught how to calculate the orbits on their personal computers. Throughout the mission, students will measure the daily change in the time it takes STARSHINE to circle the Earth. The students will use this information to calculate the density of the Earth's upper atmosphere. During its six-month lifetime, STARSHINE will gradually lose altitude because of the aerodynamic drag caused by the atmosphere's density and eventually will burn up like a flaming meteor approximately 60 miles above the Earth. Students will also look at daily solar images on the STARSHINE Web site and count the sunspots on the solar surface. They will plot the daily number of sunspots against the rate of change of STARSHINE's orbital period to learn how solar storms heat and expand the Earth's upper atmosphere, causing variations in its density and producing aerodynamic drag. At the end of the mission, the students will attempt to photograph the satellite's fiery reentry, and the best picture will win a prize. The STARSHINE spacecraft is an 86.6-pound hollow aluminum sphere that is 19 inches in diameter. It is covered with 878 polished aluminum mirrors that are 1 inch in diameter. The mirrors were machined by Utah high school technology students and shipped to schools in Argentina, Austria, Australia, Belgium, Canada, China, Denmark, England, Finland, Japan, Mexico, New Zealand, Pakistan, South Africa, Spain, Turkey, the United States, and Zimbabwe for polishing. On the day before landing, the satellite will be deployed from its hitchhiker getaway special canister in Discovery's payload bay by a spring ejection system at an altitude of 205 nautical miles. A combination of spring rotation and tipoff will cause it to rotate about its pitch and yaw axes at a rate of one revolution per minute. This angular motion, combined with STARSHINE's orbital translation rate of 2 degrees per second, will produce flashes of sunlight from its mirrors every few seconds. Project STARSHINE plans to launch one satellite per year over an 11-year solar cycle. Just as soon as STARSHINE 1 gets into orbit and begins its twinkling trek across the twilight sky, project officials plan to push ahead with preparations for STARSHINE 2. The basic spacecraft structure for STARSHINE 2 has already been built by NRL, and Utah high school technolgy students are working on the mirror blanks. |
| Benefits |
| The principal objectives of Project STARSHINE are educational and motivational. If students help "build" the spacecraft (by polishing its mirrors), they should be more excited about tracking it and using it to measure upper atmospheric density and the response of that region of the atmosphere to solar storms. Project STARSHINE is giving precollege students a chance to work with real space hardware and learn how to do precision work on elements of that hardware. They also learn about satellite orbits and Earth's upper atmosphere and the interaction between the Earth's and sun's atmospheres and magnetospheres. The participants use the Internet to obtain knowledge, report their measurements, and communicate as team members with students in other countries. They are taught how to make precision optical measurements and use precision timing systems to make those measurements, and they learn something about observational astronomy and amateur radio. In short, they learn that science and engineering and technology can be fun and still produce useful results. The project has received overwhelmingly positive responses from teachers and students around the world--before the satellite leaves the ground. When the satellite completes its six months in orbit, project officials believe that they will have built up a cadre of student participants who will be interested in becoming even more involved in future projects of this nature. If Project STARSHINE is able to fly a satellite every year throughout an 11-year solar cycle, as presently planned, generations of students will learn the basic principles of solar-terrestrial physics. To further this end, the project plans to post daily white-light, ground-based images of the sun on its Web site as well as satellite images in other wavelengths and will link to other solar activity indices in Boulder, Colo. In the fall, the project will begin posting auroral images as well. Besides educating and motivating students, Project STARSHINE may have scientific benefits. If enough students do serious tracking of the spacecraft to get good orbits, especially during the terminal phase of the flight, the project might be able contribute to the pool of knowledge of the average density of the atmosphere in the 60- to 120-mile altitude regime. Since STARSHINE is spherical, it has a much more unifom drag coefficient than spacecraft with solar arrays and helical antennas and other structures protruding from them, so the density measurements that will be made from tracking STARSHINE will be more precise than those from tracking other reentering spacecraft. |
Editorial/Technical Comments: ShuttlePresskit
