Perfect Launch Begins 10-Day Shuttle Mission : Space: Columbia is to deploy one satellite before retrieving another one in danger of crashing to Earth.

With three weeks of bad weather and mechanical difficulties on Pad 39a behind it, the space shuttle Columbia on Tuesday left Earth behind as well, reaching orbit after a perfect launch that began the race to rescue a failing scientific satellite.

Taking advantage of calm weather between a departing cold front and an incoming warm front, Columbia lifted off at 4:35 a.m. PST, precisely two one-hundredths of a second after the opening of its launch window.

“I don’t think I’ve ever seen a cleaner countdown and launch,” said NASA Administrator Richard H. Truly. “What a marvelous way to start the ‘90s.”

The launch--the eighth since the 1986 Challenger disaster and the 33rd overall--also brought relief to scientists with experiments aboard the endangered Long Duration Exposure Facility, which will crash into the Earth’s atmosphere in March if Columbia cannot retrieve it.

“There were times when we wondered if this day would ever come about,” said chief LDEF scientist William Kinard of the National Aeronautics and Space Administration. “It sure was down to the wire.”

The shuttle will begin its second day in orbit today by launching a Navy communications satellite at 5:20 a.m. PST, and then initiating a complicated, balletic series of orbital maneuvers that will allow it to rendezvous with the crippled LDEF at 6:44 a.m. PST Friday.

The SYNCOM IV satellite launched by Columbia will be the fifth in the Navy’s Leasat series, which provides worldwide high-priority communications between aircraft, ships, submarines and land bases. Designed by Hughes Aircraft Co. specifically for launch from the shuttle, the 17,000-pound satellite is flung from its cradle in the payload bay like a Frisbee.

About 45 minutes after the satellite is ejected from the shuttle, its liquid-fueled engine will fire for the first of several burns that will gradually boost it into a geostationary orbit 22,500 miles above the Earth’s surface almost directly above the Gilbert Islands in the Pacific Ocean.

The five astronauts will then turn to their primary task, chasing down and capturing the school bus-sized LDEF, which contains 57 experiments designed to test the effects of prolonged exposure to the hazardous environment of space on materials used to construct spacecraft and satellites.

Launched in 1984, LDEF was scheduled to be retrieved within a year, but scheduling delays and then the Challenger explosion prevented pickup. Friction from the outer fringes of the atmosphere is currently causing LDEF’s orbit to deteriorate by about half a mile per day. It will burn up in March if Columbia should not be able to retrieve it.

Because no satellite has ever been recovered from space after exposure of more than a few days, researchers believe LDEF--which has been in orbit for 5.5 years--will provide them with a wealth of data for use in constructing the proposed space station and the defensive satellites of the Strategic Defense Initiative.

“It should give us an understanding of what materials stand up best and what materials we should use on the space station,” said George Hopson, director of space-station research at NASA’s Marshall Space Flight Center in Huntsville, Ala.

Immediately after launch, Columbia was in a more elliptical orbit than LDEF and about 1,500 nautical miles behind it. To catch up and match orbits will require seven firings of the orbital maneuvering system rockets and six firings of the less powerful reaction control system, whose main function is to orient the orbiter in space.

LDEF will be 182.4 nautical miles high when Columbia catches up with it. When the shuttle gets within a few hundred feet of LDEF, the mission commander, Navy Capt. Daniel C. Brandenstein, will fly it into docking position manually. “Dan is one of the best stick-handlers I’ve ever seen,” said NASA flight director Al Pennington.

After mission specialist Bonnie J. Dunbar grasps LDEF with Columbia’s remote manipulator arm, Marsha S. Ivins will spend about 4.5 hours photographing all the experiments on board the satellite before Dunbar tucks it away in the payload bay.

During the 10-day mission, the second-longest to date, the five astronauts will perform a variety of medical experiments, including taking echocardiograms of their hearts, that will help NASA prepare for 16-day and 28-day missions in the future.

They will also carry out two separate series of experiments growing protein crystals to test processes that might be used for producing drugs in space, measure the effects of light and microgravity on the circadian rhythms (24-hour-cycles) of a fungus called neurospora, melt and recrystallize solids that are used in the electronics industry, and attempt to photograph lightning.

Many aspects of the mission, including the rendezvous with LDEF, will be documented with the IMAX camera, which provides highly dramatic large-screen motion pictures.

Brandenstein, 46, is making his third shuttle flight. A native of Watertown, Wis., he became a naval aviator in 1967, and flew 192 combat missions in Vietnam. He logged more than 5,200 hours of flying time during the war and as a Navy test pilot. He is married and has one daughter.

Columbia’s pilot, Navy Lt. Cmdr. James D. Wetherbee, 37, is making his first shuttle flight. A native of Flushing, N.Y., Wetherbee became a naval aviator 10 years after Brandenstein. He helped test, and later flew, the F/A-18 fighter until his selection as an astronaut in 1984. He and his wife have two children.

Dunbar, 40, is making her second shuttle flight. On her first, she was responsible for operating the Spacelab. A biomedical engineer born in Sunnyside, Wash., she was an “engineer of the year” at Rockwell International before joining NASA as a payload officer/flight controller in 1978. She also is married.

Ivins, 38, and mission specialist G. David Low, 33, are both rookies. A native of Baltimore, Md., Ivins is an aerospace engineer who wanted to be an astronaut since the age of 12. She joined NASA in 1974 as an engineer in the Crew Station Design Branch. She also has been a simulation engineer, helping to modify NASA’s Gulfstream aircraft so that they mimic the flight characteristics of the shuttle.

The Cleveland-born Low is a rarity among astronauts: second-generation NASA. His father, the late George M. Low, was instrumental in carrying out the Apollo program that landed U.S. astronauts on the moon in 1969. The younger Low is an aeronautical engineer who joined the spacecraft engineering section of NASA’s Jet Propulsion Laboratory in 1980. He has also worked on the Mars Observer project.

Columbia is scheduled to land on the concrete runway of Edwards Air Force Base in Southern California at 2:57 a.m. PST on Jan. 19.

Long-Duration Exposure Facility Structure: 12-sided framework with experiment trays Length: 30 ft. Diameter: 14 ft. Weight: 8,000 lbs. Launched: April, 1984