To view this story on the web go to http://www.sunspot.net/content/cover/story?section=cover&pagename=story&stor yid=1150520209023 ------------------------------------------------------ Headline: Pioneer lives up to its name Subhead: Probe: Almost three decades after its launch, Pioneer 10 dutifully sends data back from the fringes of the solar system to a handful of loyal listeners on Earth. By Michael Stroh SUN STAFF This weekend, Larry Lasher will hover around an antiquated NASA control panel, eagerly waiting for a small red light to wink. When it does, the 63-year-old scientist can breathe easy once again: His old pal Pioneer 10 is still alive. The Volkswagen-sized probe was once a space-age celebrity. In the 1970s, it became the first man-made object to venture beyond Mars and explore the gassy giant Jupiter before soaring toward the stars. The craft carried a gold plaque of a naked man and woman and a diagram of our solar system - a cosmic business card in case Pioneer bumped into an alien. Today the geriatric craft has been largely forgotten by the public and officially mothballed by NASA brass. But Lasher and a small group of agency old-timers have quietly refused to abandon the probe, which continues to faithfully transmit a dribble of scientific data back home even after 28 years in space. They come in on their days off and in the dead of night to tune in to its signal. "You don't want to let it go," says Lasher, who coordinates the project from the Ames Research Center in Mountain View, Calif. "Why put Pioneer out to pasture when it could still be out there offering valuable information?" They know the clock is ticking. Careening through space at 27,700 mph, the craft is 7.12 billion miles from Earth and will soon sail beyond the range of the National Aeronautics and Space Administration's most sensitive deep-space antennas. Before its faint signal disappears for good in the next few months, the nostalgic Pioneer groupies, many of them near or past retirement age themselves, are quietly hoping their spacecraft might pull off one last scientific coup: becoming the first craft to send back data from interstellar space beyond our solar system. Launched from Cape Kennedy on March 2, 1972, the spacecraft was designed to last for 21 months. Three hundred and forty-five later, the probe and its plutonium power supply have outlived many of its creators. "It just keeps on going and going," says Lasher with a hint of engineer's awe. "It's lasted much longer than its warranty." Despite Pioneer's long list of accomplishments, a budget-strapped NASA decided in 1997 that the millions of dollars it cost to operate the probe was siphoning too much cash from newer missions. One month after Pioneer's 25th anniversary party, NASA pulled the plug. "As far as headquarters are concerned, it's considered dead," says James Van Allen, who has been involved with the Pioneer 10 mission for more than 30 years. Van Allen is no stranger to space. He helped design the first U.S. satellite, Explorer 1, and discovered the radiation belts around Earth that now bear his name. Yet the 86-year-old astrophysicist says Pioneer 10 holds a special place in his heart. "It's been my old friend all these years, the most important part of my professional life since 1969," he says. Each day he comes into the office at the University of Iowa and pores over data from Pioneer's Geiger Tube telescope, the only one of Pioneer's 11 original scientific instruments still working. Over the years, he says, the spacecraft has provided fodder for numerous groundbreaking research papers, not to mention dissertations for his students. Not long before the project was canceled, Van Allen gave a eulogy for Pioneer 10 at the National Air and Space Museum, chronicling its extensive list of accomplishments. Soon after, Van Allen says, he began "working the halls" trying to keep Pioneer 10 alive. In Ames, Larry Lasher did the same. Lasher bought Pioneer some time by convincing NASA that the distant craft would provide good training for controllers prepping for the 1998 Lunar Prospector mission to the moon. Last summer, Lasher, Van Allen and the other Pioneer supporters got another lucky break. Glenn Mucklow, a physicist at NASA's headquarters in Washington, wanted to use the spacecraft to study weak signals. "It's the only thing we've got out there and it took us 28 years to get it there," says Mucklow. That made it the perfect choice. The craft's transmitter broad casts at 8 watts, equivalent to the power of a night light. By the time it reaches Earth, nearly 11 hours later at the speed of light, the signal "is almost science-fiction weak," says Lasher - less than a millionth of a trillionth of a watt in strength. Mucklow says that learning how to extract data from such a faint signal would be valuable not just for future NASA missions but also for communications troubles here on Earth. Though happy that Pioneer is being put to use, researchers hope the spacecraft might bring home an even bigger scientific trophy before it disappears into the dark of space: pinpointing the heliopause. The heliopause is the boundary where particles rushing outward from the sun, known as the solar wind, collide with particles streaming in from interstellar space. Its location is considered one of the great unanswered questions of astrophysics. Using his Geiger Tube telescope, Van Allen is sifting through the data looking for an indication that the solar wind is no longer detectable. That's when he'll know Pioneer has crossed the divide. He knows the chances it will happen before Pioneer sails out of range are slim, but there's always hope. Even if the craft does continue to limp along, there are other problems. Every six months the craft's antenna must be repointed toward Earth so antennas can pick up its faint signal. The maneuver hinges on a cranky 30-year-old DEC PDP 11 computer that's constantly on the verge of a breakdown. For reasons engineers still don't understand, it's the only device in all of NASA that Pioneer responds to. "It's a cliffhanger every time," says Mucklow. To keep the antique machine running, engineers have had to scavenge circuit boards, fans, power supplies and other parts from the skeletons of three other PDPs lying around the building. But when engineers ordered Pioneer 10 to repoint its antenna last July, the maneuver didn't work. So Lasher and his team have had to wait until this month for Earth to naturally align itself with the spacecraft's antenna to contact the spacecraft. The Pioneer veterans realize that neither they nor their spacecraft are getting any younger, so they're eager to resume their hunt for the heliopause. "Van Allen keeps calling me saying, 'Where's the data? Where's the data?'" Lasher says. ------------------------------------------------------ To view this story on the web go to http://www.sunspot.net/content/cover/story?section=cover&pagename=story&stor yid=1150520209023 == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
