Satellite Seeks Space Ride

Triana would hover around the Lagrange libration point L1, where it would orbit the Sun with the same period as Earth. From that vantage point a million miles away, the satellite would gaze at the sunlit portion of Earth, probing cloud cover, pollution, ozone, aerosols, water vapor, ocean color, and vegetation. "We plan to use Triana to monitor global warming," says Francisco Valero of the Scripps Institution at the University of California, San Diego, who leads the Triana collaboration. "The fundamental concept is to have the synoptic, high time-resolution view with sunrise-to-sunset coverage of almost every point on the planet." Until now, adds Warren Wiscombe of NASA's Goddard Space Flight Center, "we would patch that kind of information together from many satellites. It's always a bit of a kludge."

One of Triana's instruments, EPIC, would take an hourly snapshot of the solar energy reflected by Earth in 10 spectral bands for ultraviolet, visible, and near-infrared wavelengths (317-905 nanometers) with a spatial resolution of 8-14 kilometers. Another, NISTAR, would record the energy reflected by the full sunlit Earth at ultraviolet, visible, and infrared wavelengths (0.2-4 micrometers) as a function of time. NISTAR would also measure the planet's total thermal radiation for longer wavelengths, out to the far infrared (4-100 micrometers), which arise mainly from emission. A third set of instruments would monitor solar flares and the solar wind to study and predict space weather.

Despite its strong scientific credentials, the satellite nicknamed GoreSat has not managed to shake off the albatross of its White House conception, which put it on the fast track but tarred it politically. "Gore cut loose from Triana. He floated the idea, but it went forward without his help," says Wiscombe. "[Gore's] original idea of a TV camera in the sky was dead on arrival. We quickly moved well beyond that."

NASA invited space scientists to submit competing ideas for a mission to L1, but never asked if they wanted to go there. The omission backlashed: Triana has been beset with complaints that it bypassed peer review. The complaints eased a bit after the National Academy of Sciences, at Congress's bidding, issued a report on Triana early last year. But critics refuse to forget that the academy's endorsement of Triana's goals came late in the satellite's planning.

Another sticking point is Triana's estimated cost, which ballooned to about $100 million. Depending on who's counting, the launch is either a free hitch with the shuttle, or it as much as doubles the tab.

Triana lost its launch when NASA, in accord with President Bush's proposed 2002 budget, cut back the number of shuttle flights from eight or nine a year to six. After payloads bound for the International Space Station, the agency's priorities are a maintenance mission to the Hubble Space Telescope and a microgravity experiment. NASA's tight budget and an expected $4 billion overrun on the space station have dealt blows to many projects—a mission to Pluto, the Vegetation Canopy Lidar, prototype reusable launchers X-33 and X-34, and a habitation module and other space station accessories, to name a few. But putting Triana on ice is unusual because the satellite is built and ready to go.

"Not to proceed at this point would be a major, embarrassing waste of scientific talent and taxpayers' money. We must push forward," says Valero. He is exploring various launch options, including a later shuttle ride, an expendable rocket, and flying on the European Space Agency's Ariane 5 rocket. Keeping politics in the mix, Valero points to the Bush administration's interest in global warming as perhaps boding well for Triana.