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Earthbound scientists jubilant as Spacelab data start pouring in

Luigi Napolitano looked around the room and asked, ''Does anybody have a cup of water?'' When someone handed him a cupful, he dipped his thumb and forefinger into it, pulled them out and spread them until a tiny column of water formed in between them.

Then the aerodynamics professor from the University of Naples, Italy, launched into a lengthy, exuberant explanation of his fluid-physics experiment, which had been successfully conducted aboard Spacelab earlier that day.

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His enthusiasm is clearly shared by many of his colleagues as data come streaming back from their experiments aboard the European Space Agency's manned, reusable orbiting lab.

Up to now, ''We've gotten rather limited data back, but what we've seen so far is fascinating,'' says Marsha R. Torr. Along with her husband, Douglas G. Torr, the Utah State University physicist is using a $4 million imaging spectrometric observatory (ISO) to study Earth's dayglow. The dayglow phenomemon is visible in the night sky at low and middle altitudes. It's caused when molecules in the atmosphere, split by the sun's ultraviolet radiation during the day, reform after the sun sets. ''We had a very exciting first turn-on of the instrument,'' she says.

Initially, the device was to activate automatically about two minutes after Spacelab was to lose the tracking and data relay satellite (TDRS). ''But we were able to get on the voice loop and have one of the engineers turn the instrument on 18 seconds before LOS (loss of signal) and we saw 18 seconds of data,'' she says.

That fast action enabled her team to confirm the unit's operation without having to wait another 40 minutes for Spacelab to come within range of the TDRS.

''There has been just a tremendous advance in this kind of (quick response) capability that we haven't seen before,'' she says.

The data from her device are being collected at the Spacelab Data Processing Facility at the Goddard Space Flight Center, in Greenbelt, Md. ''We'll get the rest (of the data) from Goddard in about three to six months,'' she says.

Dr. Torr also points to one aspect of the Spacelab system that marks a major shift in space science research. Citing the two undergraduate students participating here on her research team, she says, ''Spacelab has taken space science out of the hands of the older, established scientists and has opened it up.''

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For Marcel Ackerman of the Institut D'Aeronomie Spatiale de Belgique in Belgium, the presence of trained scientists aboard Spacelab is an invaluable asset in collecting the high-quality data he seeks.

His instrument, called the grille spectrometer, is designed to study the composition of Earth's atmosphere at infrared wavelengths.

''The calibration of the instrument was run by the crew,'' he says. ''They had a reference spectrum to use for comparison.''

That calibration process was designed to make sure that the instrument retained its high accuracy despite the vibrations it experienced during takeoff.

Unfortunately, the programmable spectrometer missed 4 of more than 30 runs because one of the onboard computers sent it some incorrect timing data.

Still, Dr. Ackerman is pleased with what he's getting.

''The data are extremely clean, of excellent quality,'' he says.

Information from his experiment will not only be used in models of how the atmosphere works, but he says it will also be used as baseline data for the National Aeronautics and Space Administration's upcoming Upper Atmosphere Research Satellite.

The crew's presence has in fact been a lifesaver for some experiments.

''The 'red shift' is certainly building a strong reputation on their ability to repair things. They're repairmen extraordinaire,'' says Charles R. Chappell, Spacelab 1 mission scientist. He was referring to mission specialist Robert A. R. Parker and payload specialist Ulf Merbold.

Dr. Merbold saved four materials-science experiments by troubleshooting a problem that disabled two of three heating facilities aboard Spacelab. He was able to get one of the two working again.

Dr. Parker crawled into his bunk, closed the sliding door, and used his sleeping bag to store film while he repaired a jammed film magazine for a high-resolution camera. Talking later with controllers on the ground, he said, ''As you might well imagine, having probably done this yourself, it's even more fun up here with sleeping bags flopping all over you, and spools rattling around in the dark.''

The camera is designed to test the potential of high-resolution photographs for mapping purposes. The black-and-white and infrared photos taken with this camera are expected to be an order of magnitude higher than images currently available from Earth observation satellites.

In both cases, the repairs involved were never a part of crew training, STS-9 officials point out.

The red shift isn't the only one to get such kudos. Dr. Napolitano credits Byron Lichtenberg from the Massachusetts Institute of Technology for ''saving my experiment. . . . It shows what you can do when you have trained, intelligent, educated men on board.''

As the mission heads into its last few days, however, not everyone has experienced glowing success.

''I'd like (this Spacelab mission) a lot better, if we were doing better,'' says William W. L. Taylor, a plasma physicist with TRW's Space and Technology group.

His experiment involves using high-energy electron beams to study the magnetic fields and the plasma, or ionized gases, that surround Earth. Unfortunately, a crucial element of the Japanese-made particle accelerator - the electron beam accelerator - has yet to work at all on high power, roughly 15 kilowatts.

The high-power setting is crucial not only to some of the studies of Earth's mantle of magnetic fields and charged particles. It also prevents Dr. Taylor and his co-investigators from verifying in space something called a virtual antenna.

Basically, this uses a high-energy electron beam and Earth's magnetic field to transmit radio signals to the ground. Taylor and his colleagues had hoped to pulse the beam at 1 and 5 kilohertz rates to see if the signals were received at waiting ground stations. One potential application for this technique, Taylor says, is very low-frequency communications with submarines.

''All of us can sense the concern'' over lost experiments, Dr. Chappell says. ''There is strong empathy among investigators when colleagues run into trouble . . . but you have to put those losses into perspective. We're still getting a flood of new science material every day.''

Indeed, it's the flood of new science data and the enthusiasm of the investigators that have prompted NASA to add an extra day to the mission, weather at the landing site permitting.

After polling the investigators, Chapell says, some 70 percent supported the extension, and the remaining 30 percent didn't care one way or the other.

An extra day will add a couple of items to the science agenda. In addition to conducting more life-science experiments, mission planners expect to devote time to shuttle glow and solar seismography.

The shuttle glow phenomenon has been experienced to some degree on every shuttle flight, and is suspected to come from the collision of oxygen atoms with the orbiter's surface. Experiments conducted during STS-8 showed that the glow appears to vary depending on the material involved. Dr. Torr's ISO will be used to examine the composition of the glow.

A better understanding of the glow and how to control it is crucial: Some scientific instruments on future flights, including the space telescope, could be affected by the light emitted.

Solar seismology, studying the weak oscillations of the sun, is a relatively new field of study, says Karl Knott, European Space Agency project scientist for this mission. ''The phenomenon was not known when the experiments (for this mission) were first proposed several years ago,'' he says.

By studying these oscillations, scientists can get a better understanding of the makeup of the sun's interior.