STS-77 Mission Control Center Status Report 8 Wednesday, May 22, 1996 4 p.m. CDT Endeavour's crew spent another day in space devoted to precision flying as they deployed the second satellite of their mission, moved nine miles away, and then returned to within a half-mile to study the satellite's stability. Four and one-half hours after releasing and separating from the Passive Aerodynamically Stabilized Magnetically Damped Satellite-Satellite Test Unit, or PAMS-STU, early this morning, Endeavour returned to a position about 2,000 feet from the satellite. Commander John Casper and Pilot Curt Brown kept Endeavour near PAMS-STU to allow ground-based researchers to attempt to track the satellite with instruments mounted in Endeavour's cargo bay. PAMS-STU was ejected from its canister in Endeavour's payload bay at 4:18 a.m. central time today. It was placed in an intentionally unstable orientation and it is anticipated that it should slowly reorient itself to a stable attitude. The PAMS-STU technology demonstration investigates the use of natural, aerodynamic stabilization to orient a spacecraft properly, a technique that could prolong the lifetime of future satellites by reducing or eliminating the requirement for attitude control propellants. During the two hours Endeavour held position this morning, investigators noted that the satellite had not yet stabilized and they did not obtain a strong lock on the satellite using the laser-based tracking instruments aboard the shuttle. However, two more such close encounters with the satellite are planned later in the flight to check its progress. Those stationkeeping exercises are expected to last up to six and one-half hours each. The astronauts have begun an eight-hour sleep period and will awaken to begin Flight Day 5 at 11:30 p.m. central time today. Flight Day 5 will be dedicated to continued scientific investigations in the Spacehab module. All of Endeavour's systems continue to perform well as the orbiter circles the Earth every 90 minutes at an altitude of 175 statute miles.