For physics professor Phil Scherrer, the last nine months have been a lesson in what it means to be lost in space.
That's because the $1.2 billion spacecraft carrying an experiment Scherrer and his 20-person team have been working on since 1986 has spun out of control several times. These snafus have jeopardized their study of the sun's interior seismology.
NASA and the European Space Agency launched SOHO -- the Solar and Heliospheric Observatory -- in December 1995, and it operated smoothly for two years. But during routine maintenance operations in June 1998, NASA ground controllers in Maryland lost contact with the craft. It drifted for several months.
By September, controllers had managed to locate and restart SOHO. But in late December, the third of three gyroscopes aiming the craft toward the sun went out. Programmers scrambled to write software for a gyroless mode of operation.
SOHO is back on track again, but not without lingering consequences. The craft went up with enough fuel for 80 years but burned off so much in recovery efforts that its lifespan may have been cut to 20 years. And the mishaps hurt research efforts, too. An important goal of the experiment is to help scientists better understand the source of the sunspot cycle, which affects Earth's weather and electromagnetic field. But the disruptions in SOHO's operations mean part of the 11-year pattern went unobserved.
Still, Scherrer is optimistic about the craft's future: "The things we were most worried about breaking have broken now."
