ORBITING some 230 miles from Earth, the self-styled astronaut "dog crew" is showing off one of the space shuttle's unique capabilities - launching and retrieving satellites.
There are two of them on this mission - a solar observatory and an experimental laboratory. Their temporary deployment gives scientists research opportunities they could enjoy in no other way.
As pilot Kenneth Cockrell observed before his spaceship Endeavour left Cape Canaveral, Fla., last Thursday, "the only method we have in the world right now to retrieve something [in space] and bring back anything of any size at all is the US space shuttle."
Endeavour's astronauts helped solar physicists carry out just such a job over the weekend with the Spartan 201 free flying instrument carrier. The $8-million package is equipped to study the sun's outer atmosphere. Spartan has been taking measurements just as the European Ulysses spacecraft is passing 213 million miles above the sun's north polar region. This allows for simultaneous observations that solar physicists hope will help resolve a surprising mystery.
Spartan was in space just a year ago during a mission of the shuttle Discovery when it discovered unexpectedly hot gas above the sun's south pole. Spartan investigator John Kohl of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., says "the ultimate goal" now is to "confirm this discovery and perhaps explain how gas escapes from the sun to form the high-speed solar wind."
This solar wind of electrically charged particles blows away from the sun at speeds of a million miles an hour. As it brushes past Earth it causes aurorae and magnetic storms that disrupt communications and electric power grids. These disruptions result in estimated losses of $100 million a year worldwide, giving scientists reason to learn all they can about the origin and nature of the solar wind.
Endeavour's crew - which for reasons known largely to themselves like to be called the "dog crew" and often bark on the way to the launch pad - was about to bring Spartan back into the shuttle's cargo bay at this writing and release the second satellite - the Wake Shield laboratory - toda#y.
Endeavour mission specialist James Newman calls the Wake Shield "a scientist's dream." The laboratory, a 12-foot diameter flying saucer, will grow ultra-pure semiconductor wafers as it trails behind Endeavour. The lab's position in Endeavour's wake helps shield it from bombarding atoms and meteoritic particles.
The Wake Shield program aims to prove techniques for producing such high-quality material in commercial quantities for advanced electronic uses.