NASA intends to finish and fly the Glory climate-monitoring satellite, reversing a decision the U.S. space agency made just six months ago to cancel the $208 million mission. Facing budget pressure, NASA Earth science officials said early this year that the agency was looking for options short of launching a dedicated satellite for putting the spacecraft's featured sensor, a greenhouse gas measuring instrument, in orbit.
By the time NASA rolled out its 2006 budget request in February, the decision had been made to cancel Glory while continuing work on the spacecraft's aerosol polarimetry sensor. NASA later said it intended to add the instrument to one of the new generation of U.S. polar-orbiting weather satellites in development.
The decision to cancel the Glory mission was itself something of a reversal for NASA, which has long planned to contribute an aerosol polarimeter to the multiple-spacecraft National Polar-orbiting Operational Environmental Satellite System (NPOESS) that is slated to start launching around the end of the decade.
In the summer of 2003, however, NASA announced at the conclusion of an international Earth Observation Summit hosted by U.S. State Department, that the agency would be accelerating development of the sensor and launching it on a dedicated satellite, Glory, in 2007, a move that would speed the introduction of the new observation capability by at least a couple of years. U.S. governmental officials pointed to the Glory announcement as a sign of the United States' commitment to studying the causes and consequences of climate change.
NASA also announced that Glory would be equipped with a second instrument, the Total Irradiance Monitor, that would continue observations being made by another NASA science satellite launched in 2003, the Solar Radiation and Climate Experiment, or SORCE. The two instruments together, NASA said at the time, would improve scientific understanding of whether human activities or natural climate variability are more to blame for global warming.
NASA's decision less than two years later to scrap the free-flying Glory mission and fall back to waiting for NPOESS to fly the greenhouse gas sensor did not sit well with a number of powerful politicians in the U.S. House of Representatives and Senate.
No fewer than five lawmakers wrote NASA urging the agency to proceed with the standalone Glory mission, including House Science Committee Chairman Sherwood Boehlert (R-N.Y.) and Rep. Frank Wolf (R-Va.), the chairman of the House Appropriations science, state, justice and commerce subcommittee. Wolf's Northern Virginia congressional district is home to Orbital Sciences Corp., the Dulles, Va.-based company under contract to build and launch the dedicated Glory satellite.
U.S. Sens. George Allen and John Warner, both Virginia Republicans, also sent letters to NASA in support of Glory, as did Sen. Barbara Mikulski, a Maryland Democrat who would like to see the Greenbelt, Md.-based Goddard Space Flight Center proceed with the climate-monitoring mission.
Parochial interests aside, lawmakers also could point to a 2005 National Research Council report, "Earth Science and Applications from Space: Urgent Needs and Opportunities to Serve the Nation," which questioned the feasibility of relying on NPOESS to host instruments from a small but growing number of canceled or scaled back NASA science missions, and called on the space agency to commission an independent review before canceling the Glory mission.
NASA officials informed lawmakers this spring that the agency was taking another look at its Glory decision and that for the time being Orbital Sciences would continue its work on the Glory spacecraft bus. That bus itself is a leftover from the Vegetation Canopy Lidar mission that NASA canceled in 2001 as development of its complicated laser sensor continued to fall further behind schedule.
Scientists have said they would like to see Glory on orbit by 2008 - early enough to overlap with the SORCE mission and in time to observe the solar minimum, an extreme in the sun's 11-year activity cycle. Proponents of the mission said Glory would help shed light on how much global warming is attributable to human factors such as pollution and natural climate variability caused by the sun.
Ted Hammer, deputy flight program director for NASA's Earth sun systems division, downplayed the role political pressure played on the U.S. space agency's about face. "I'd like to convince you that it was just us doing our due diligence," Hammer said in a July 21 interview. "What you want to do as an agency is to do the right thing, to see that you get the optimal solution and lowest risk approach for providing the science that we are required to support."
Hammer said NASA is now targeting late 2008 for launching Glory. Hammer said NASA estimated in 2004 that Glory would cost about $208 million. While there has been some cost growth, Hammer said it is less than 20 percent.
An update to NASA's 2006 budget request, sent to Congress July 15, requested an additional $88.3 million for the agency's Earth-Sun System programs to, among several other things, "fully fund a standalone Glory mission."