Music of SPHERES
Satellite project could accelerate space research
If all goes as planned, the unmanned Russian supply spacecraft Progress 12 will lift off Thursday from a remote launching pad in Kazakhstan, ferrying experimental gear to the International Space Station.
And in an old factory building on the outskirts of Kendall Square in Cambridge, the earthbound engineering team from Payload Systems Inc. will mark the occasion as a significant milestone for a project that could accelerate space research. Payload is building a grid of volleyball-sized satellites programmed to rendezvous, separate, and fly in formation. Eventually, they will conduct microgravity experiments and help astronomers identify planets in the far reaches of space.
"What you really want is to take a picture of a planet that has water on it, a planet that looks like Earth," said Javier de Luis, the chief executive and chief scientist at Payload.
Astronauts will begin initial tests inside the space station this fall, but the concept is still years away from deployment. The project, called SPHERES, for "synchronized position hold, engage, and reorient experimental satellites," is relatively small by NASA standards. And it has been delayed a few months because its first payload of equipment -- a beacon and a beacon tester -- had been scheduled to be sent into space last spring on a US space shuttle. When the shuttle fleet was grounded in the aftermath of the Columbia breakup, the researchers turned to the Russians to deliver the cargo.
In many ways, the SPHERES project and the 19-year-old private firm started and run by MIT graduates embody the paradox of space research and its long timetables. While public attention and funding decisions are focused on the immediate future of the space program, post-Columbia, the researchers who package scientific experiments for the space station must fix their sights years into the future.
Even as scientists pore over images from the Hubble Space Telescope, for example, the SPHERES team is readying technology two generations ahead of Hubble. The technology could enable researchers to capture images "orders of magnitude better than what the Hubble does," de Luis suggested. NASA's long-term plan is to operate the satellite grid as a "terrestrial planet finder," with each satellite flying in a programmed position and taking in light from distant stars, and astronomers recombining the light images and stitching them together to pinpoint planets. Such an approach would afford scientists a far wider field of vision than Hubble.
Another potential use of the SPHERES technology would be helping satellites dock together for refueling and repairs. That application is of interest to NASA and the Department of Defense, the agencies funding and monitoring the project, because it promises to lower the cost of building and maintaining space systems. The immediate goal, however, is simply to test the communications equipment developed by Payload for its prime contractor, David W. Miller, director of MIT's Space Systems Laboratory. The first task is to make sure the beacon and its sensors don't interfere with the other electronic systems mounted inside the space station. Formation flights won't begin until after the first satellites -- each packed with internal propulsion and command-and-control systems -- arrive on another Progress mission in November.
Miller and de Luis, MIT graduate student colleagues in the 1980s, have collaborated on numerous space experiments. SPHERES is only the latest. "It's a laboratory on the International Space Station for conducting fundamental research into satellite formation flight and docking," Miller said. SPHERES, a $1 million project, will be the sixth research laboratory his lab team and Payload have put into space together, all involving microgravity and the control of satellites; the most recent, in 2000, was called MACE, for mid-deck active control experiment, which allowed space station astronauts to study vibration control for precision optical satellites.
The formation-flying concept has its roots at MIT, where Miller teaches as associate professor of aeronautics and astronautics. Under an initial contract from the Air Force, the school's space systems lab began looking into designing and programming satellites to maintain relative space and motion and perform a range of missions. Miller's undergraduate class developed the hardware, while his graduate students worked on the software. The concept was initially tested three years ago on a KC135, similar to a Boeing 707 jetliner, that was used by the Air Force for parabolic flight research.
"At the time, we thought we should bring this up to space," Miller recalled. "You only get 10 really good seconds of weightlessness on the KC135. On the space station, we could get minutes to hours."
Payload was founded in 1984 by MIT PhDs Byron Lichtenberg and Anthony Arrott to provide support services to researchers in life sciences, material sciences, space, and underwater environment. But space research was the priority from the start. "We're space cadets," explained de Luis, a long-time Payload project manager who purchased the company in 1995. "We like to work on things that fly in space."
Payload also has had a history of international collaboration. It was the first American company to place an experiment (involving protein crystal growth) on Russia's space station Mir, during an earlier hiatus in US shuttle operations after the 1986 explosion of the Challenger. And it has long been tracking the influence of gravity on cellular processes.
The company, with just 30 employees, competes for NASA and Pentagon contracts with both small private companies and conglomerates such as the Boeing Co. Payload's managers, space science veterans with strong ties to NASA, say that by staying small they can better work with the space agency to help determine the goals of an experiment.
"We're able to very often influence the early-stage design of a program to shape it to be as agile and nimble as possible," said Julianne Zimmerman, a Payload senior engineer.
One thing they share with Boeing and everyone else in the space business is an environment of uncertainty, as government officials reassess the US space program in the wake of the Columbia's destruction. The accident on Feb. 1 took an emotional toll -- both de Luis and Zimmerman had met some of the astronauts -- but it has not deterred them. And de Luis said he doubts it will result in a long-term loss of funding for NASA or space research.
Robert Weisman can be reached at firstname.lastname@example.org.
© Copyright 2003 Globe Newspaper Company.