WASHINGTON — A $100 million Earth-observing satellite formerly known as Triana, in limbo for more than a year, could finally be headed to orbit once construction of the international space station winds down in early 2004.
The fully assembled satellite, the subject of political controversy from the time it was proposed by former U.S. Vice President Al Gore, has been sitting in storage at NASA’s Goddard Space Flight Center in Greenbelt, Md., since late 2001.
NASA now is looking to launch the satellite on a space shuttle research flight tentatively planned for late 2004 or early 2005.
Ghassem Asrar, NASA associate administrator for Earth science, said a shuttle launch is being given serious consideration as the U.S. space agency begins to identify new missions for the orbiter fleet once space station assembly is completed.
"We are hopeful that now that the space station assembly sequence is being finalized, and as we look at the number of shuttle missions being increased, it will give us the opportunity to launch this mission," Asrar said.
The Triana satellite previously was slated to fly in late 2000 aboard STS-107, a dedicated space shuttle research flight, but the U.S. Congress in late 1999 halted work on the project pending a National Academy of Sciences review of its scientific merits. The academy ultimately found Triana to be scientifically worthwhile, but by that time the flight opportunity was missed, even though STS-107 encountered numerous delays and only now is being readied for a January liftoff.
The satellite has been renamed the Deep Space Climate Observatory (DSCVR), a change Asrar said reflects the changes the mission has undergone since it was first proposed by Gore in 1998.
Gore, who at the time was the Democratic presidential hopeful, envisioned a satellite that would beam back live, television-quality imagery of the home planet from a vantage point some 1.5 million kilometers away.
Triana’s association with Gore struck a raw nerve with Republican lawmakers, who assailed the scientific merits of the project and took steps to kill or at least delay the mission.
By the time the National Academy of Sciences completed its congressionally mandated review in March 2000, NASA had succeeded in transforming Gore’s vision into a "relevant and useful" scientific endeavor, according to the academy’s final report.
In addition to the full-color camera, DSCVR is equipped with two scientific instruments designed to measure Earth’s atmospheric ozone and aerosols, observe land and ocean surface changes, and study the role the sun plays in climate change. The spacecraft also would provide early warning of solar storms that could damage satellites and disrupt electrical equipment on Earth.
By the time the mission was revalidated, however, there were no flight opportunities on the horizon.
In 2001, the White House announced plans to cut back to six space shuttle flights a year. Priority was given to space station assembly and a Hubble Space Telescope servicing mission. As a result, NASA ordered Goddard Space Flight Center to finish the satellite and put it in storage for safekeeping. NASA headquarters offered vague assurances to the Triana team that the satellite would one day be launched.
When NASA Administrator Sean O’Keefe announced in early 2002 that the space shuttle flight rate would be further reduced from six to four per year in response to the international space station’s budget crisis, NASA Earth science officials began fielding various offers from abroad to launch the satellite at little or no cost to the agency.
O’Keefe has since reversed course on the latest shuttle flight rate plan, committing the agency to five flights a year. Asrar said he is once again focusing on a shuttle launch as the best means of delivering the satellite to orbit.
Francisco Valero, DSCVR’s principal investigator at the Scripps Institute of Oceanography in San Diego, said he is anxiously awaiting the release of NASA’s 2004 budget request in February to see if funding is included for a shuttle launch. Valero said his team also would be looking for "minimum support" in 2003. Once removed from storage, DSCVR could be ready to fly in less than a year, he said.
"We need about six months," Valero said. "We want to retest some key parts. You only get one shot."
If DSCVR is launched in late 2004, it would be the first NASA environmental research satellite positioned beyond low Earth orbit.
Once deployed from the shuttle, the satellite would employ a kick motor to travel 1.5 kilometers toward the sun to a stable orbital location known as Lagrange Point 1. From that distant vantage point, where the gravity of the sun and Earth cancel each other out, DSCVR would always have a full view of the sunlit side of Earth.
