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Jennifer was hundreds of miles from the fire and thunder of the shuttle's liftoff, but there was still good reason to feel excited. She knew that inside Endeavour's cargo bay was an extraordinary research satellite -- one that she herself helped build. After years of design, testing and assembly, "Starshine 2" was finally on its way to space! Right: With Starshine 2 on board, shuttle Endeavour left Earth at 5:19 p.m. EST on Dec. 5, 2001. [more] On Dec. 16th, shuttle astronaut Dan Tani deployed Starshine 2 into its own Earth-circling orbit. Tani severed two restraining bolts. Then a compression spring shoved the satellite through the cargo bay doors. As soon as it drifted a safe distance from the shuttle, a nitrogen gas system fired and set the satellite spinning.
Starshine 2 is an eye-catching aluminum sphere, about the size of a beach-ball and covered with glistening mirrors. Like its sister satellite Starshine 3, which was launched on Sept. 29th, Starshine 2 reflects sunlight and looks to sky watchers on Earth much like a pulsing 1st-magnitude star. Students and scientists plan to track the pair by monitoring their flashes, and so learn how satellite orbits decay in the outermost layers of Earth's atmosphere. Both satellites are the progeny of Project Starshine -- a consortium of volunteers supported by the US Naval Research Laboratory, the Space Grant Program, and NASA. "Our goal is to get students involved in space exploration -- by doing it themselves," explains project director Prof. Gil Moore. The 845 mirrors on Starshine 2, for example, were painstakingly polished by thirty thousand students in 660 schools in 26 countries.
Their parents are thrilled as well. "I have never seen my son so excited about coming to school, or staying after," says a Starshine mom from West Virginia, "He talks about all of the space projects like Starshine. It's really wonderful!" Right: Click on the image to view an animation of Starshine 2's deployment from space shuttle Endeavour on Dec. 16, 2001. [1 MB mpeg movie] After the mirror polishing, says Moore, "the second phase of student participation is observation. We'd like to get as many students as possible to go out as often as possible to track these satellites." Starshine sightings, properly timed and recorded by students, will reveal to scientists how fast the orbits of the two satellites are decaying. "As they skim along the upper atmosphere, sparse molecules of air nip away at the crafts' kinetic energy little by little," explains Moore. As they lose energy, they fall. How fast depends on the Sun. Moore continues: "The thickness and density of Earth's atmosphere changes in sync with solar activity. Storms on the Sun can produce powerful outbursts of ultraviolet radiation. When that energy reaches Earth, it causes the upper layers of the atmosphere to puff out."
Left: Explosions on the Sun bathe Earth's atmosphere in ultraviolet radiation. Click on the image to view a 4.3 MB mpeg movie of a solar flare. [more] "It's really very easy for anyone to find Starshine 2 or 3 flashing in the sky," adds Moore. "Just go to the Heavens-Above.com web site. There you'll learn when the satellites will orbit over your area." One goal for observers is to determine how rapidly the Starshine satellites spin. "We're very interested in spin," says Moore. "When a satellite moves through Earth's magnetic field, currents are induced that flow through its conducting shell. Such currents can exert a braking torque that de-spins the satellite." The Starshine spheres, because of their well-defined geometry and spinning mirrors, offer a good opportunity to study this effect.
"I emailed Dr. Moore several times and he answered," added young Jake. "I can't believe he took the time to answer my questions. It's just been great!" Such enthusiasm is common among students who have polished Starshine mirrors and then seen their work glimmering in the night sky. Eventually the satellites will descend deep enough in Earth's atmosphere to burn up. There's no danger to anyone on the ground, assures Moore. Both Starshine 2 and 3 were designed to disintegrate entirely about 80 km high, just as Starshine 1 did in February, 2000. Below: Kids of all ages work on Project Starshine. (Left) An elementary-school student grinds a mirror for Starshine 3. (Middle) Prof. Gil Moore holds a full-scale mockup of Starshine 2. (Right) Moore's wife Phyllis inside Endeavour's cargo bay gives Starshine a thumbs-up. "So far as I know," says Moore, "she's the first 71-year-old great grandmother ever to check out her payload in a Space Shuttle before launch."  "The end will be spectacular," he says. The bright fireballs might even cast shadows on the ground if they happen to re-enter at night. Starshine 2 is expected to re-enter in mid-2002, while the higher-orbiting Starshine 3 could remain aloft until 2004. The flame-outs won't mean the end of the Starshine program, though. Starshine 4 and 5 are already on the drawing board. "The solar cycle is 11 years long," says Moore. "Our goal is to monitor the upper atmosphere during all phases of the cycle using Starshine satellites launched every year or so. That means we'll need a lot of mirror polishers and amateur observers." Any more volunteers out there? Project Starshine already has thousands of student helpers -- but there's room for more. You too can sign up and participate! |
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Measuring
the spin rate is simple: Once you've determined where and when
the satellite will appear over your area, take a digital stopwatch
out and look to the sky. The viewing area should be as far from
lights, trees and buildings as possible. Go outside at least
a few minutes ahead of time so your eyes can adjust to the dark.
When you see Starshine's first flash, start the stopwatch. Count
five flashes, including the first one, then stop the watch. Email
your readings to 
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