Telescience Put To The Test

When asked by journalists during a space-to-ground press conference what he felt about the risks associated with launching such a small cargo, Wetherbee replied, ''If we want to get this great science, we must take a certain amount of risk. I think this science is worth going after.'' With the LAGEOS-2 deployment behind them, the crew could now focus their entire attention on more than a week of medical and scientific experiments in Columbia's payload bay and her middeck. Although those attached to USMP-1 were the most visible, the astronauts actually had little involvement in their operation.

In fact, their job, two-and-a-half hours after reaching orbit, was simply to turn the payload 'on'. The two experiments and SAMS then operated autonomously, with regular adjustments sent up from ground controllers using 'telescience'. ''They're getting better data than they expected,'' said David Jarrett on 25 October, in reference to the excellent performance of both LPE and MEPHISTO. ''The key element of USMP-1'', added Assistant Mission Scientist Martin Volz, ''is that we've been getting data from our experiments while they're in orbit and the science teams have been able to make adjustments on that basis.''

After being activated, LPE underwent a day of calibration of its high-resolution thermometers, which verified their ability to measure heat capacity with pulses of a billionth of a watt. ''This is a very critical step,'' said Reuben Ruiz as he watched LPE begin operations, ''since it demonstrates our ability to conduct the experiment.'' Early results showed that the unit had far higher data resolution than could be achieved on Earth. ''The operation of the experiment was initially in the automatic mode, with very little commanding from the ground,'' said LPE Principal Investigator John Lipa of Stanford University on 26 October.

''Now that the 'transition region' [between the 'fluid' and 'superfluid' states] has been reached, we are operating almost entirely in the interactive mode. This allows us to respond to events in near-real time.'' He noted that, even before the halfway mark of the 10-day mission had been reached, more than 600 commands had been transmitted to the experiment. By 30 October, as USMP-1 operations drew to a close, Lipa was telling journalists that his team had acquired more than 300% of the high-resolution temperature data they needed to rigorously test Kenneth Wilson's Nobel Prize-winning theory.

Meanwhile, the MEPHISTO researchers also calibrated their experiment for 24 hours, heating it up to 343 Celsius and checking the tin-bismuth samples to ensure that they were flawless and which segments of them were best-suited for subsequent analysis. On 24 October, co-investigator Andre Rouzard said his team had observed some phenomena that were entirely different in space from those seen in comparable terrestrial experiments. ''At first look, they seem to confirm theoretical models of what we thought would be happening in microgravity,'' he said. ''We are very pleased with the evolution of the experiment.''

As LPE and MEPHISTO continued their own research, SAMS was also gathering data on the impact Columbia's minute accelerations and thruster firings were having on the delicate experiments. Data-collecting 'heads' for the device were mounted close to both experiments. Early in the mission, Wetherbee and Baker performed a series of manoeuvres to calibrate the accelerometer and, during one OMS burn late on 23 October, the data from MEPHISTO's sensors clearly detected a 'blip' caused by vibrational disturbances. Accelerations were also recorded during LAGEOS-2's deployment.

''The data will help to define how extensively Shuttle manoeuvres affect crystal growth,'' said MEPHISTO's Assistant Mission Scientist Don Gillies on 27 October. ''That information will be extremely valuable in planning future experiments.'' In addition to measuring Columbia's vibrations, the accelerometer picked up virtually every other movement the crew made too, as the SAMS team told Wetherbee on 30 October. ''We've been keeping an eye on you during your exercise programmes, waving the RMS, launching the satellite and'', making a light-hearted reference to the Commander's exploits as drummer in the all-astronaut rock band 'Max-Q', ''your drum solos!''.

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