Interest in Free-flying Landsat Gapfiller Mission Resurfaces

N ASA and the U.S. Geological Survey are again pressing the case for building a dedicated land imaging satellite to replace a pair of old and ailing Landsat spacecraft not expected to survive the decade, according to U.S. government officials and industry sources.

The White House authorized a plan just last year to ensure long-term continuity in the collection of Landsat imagery by including a land imager on the next generation of U.S. polar-orbiting weather satellites expected to start launching around 2010.

The White House plan, the product of months of interagency negotiations, left open the possibility of the government funding one final dedicated satellite mission to bridge the gap between the demise of the increasingly creaky Landsat 7 and the launch of the first of six new civilian and military weather satellites that make up the National Polar-orbiting Environmental Satellite System (NPOESS).

A dedicated gapfiller mission has been under consideration at NASA, the agency in charge of building Landsat satellites, since an effort to commercialize the collection of Landsat imagery fell apart in late 2003 when the space agency rejected the only bid it had received from industry.

For much of 2004, NASA continued to pursue a Landsat gapfiller mission, even asking aerospace contractors for informal bids for the project. But by the time NASA sent its annual budget request to Congress this past February, the gapfiller mission had been dropped.

Charles Groat, the director of the U.S. Geological Survey, which is responsible for collecting and disseminating Landsat imagery, told Space News at the time that the gapfiller proposal was taken off the table “because of the extra funding involved and the belief that it would detract from the preferred solution.”

NASA and its sister agencies, including the U.S. Geological Survey and the National Oceanic and Atmospheric Administration (NOAA), have since shifted their focus and their budgets to the development of an Operational Land Imager that would be placed aboard the very first NPOESS satellite, dubbed Charlie 1, slated to launch in 2010.

NASA says it intends to issue a request for proposals for the Operational Land Imager in September, but firms interested bidding on the project expect the solicitation to be delayed at least two months as NASA revisits the free flyer approach.

However, Colleen Hartman, NASA deputy associate administrator for science, said the U.S. space agency “is operating under the White House policy that [the Operational Land Imager] will transition to NPOESS.”

Hartman did not confirm or deny that NASA and the U.S. Geological Survey are taking another look at the merits of conducting a free flyer, but would say only that “NASA is working with its sister agencies on the challenges facing NPOESS and an analysis will be completed in the coming months.”

NPOESS is more than $1 billion over budget, and the launch of its first satellite has been pushed back from 2009 to late 2010 at the earliest.

With continued uncertainty surrounding the NPOESS program’s cost and schedule and growing worries about the time and money it will take to develop the Operational Land Imager and integrate it aboard the new weather satellites, proponents of a Landsat bridge mission, or gapfiller, are working to overturn what they say is turning out not to be as good a solution as hoped.

“There already is a Landsat data gap that we are already taking steps to mitigate by seeking data from international sources,” said one U.S. government official working Landsat policy issues. “Because of NPOESS own problems and what we are learning about what it will take to incorporate Operational Land Imager, the data gap is widening with a fairly high degree of uncertainty as to when the data gap will close.”

Defenders of the NPOESS strategy, meanwhile, maintain that any technical hurdles standing in the way of adding Operational Land Imager to the weather satellites are surmountable and that putting it on NPOESS represents the most cost effective solution.

Policy Considerations

Dedicated Landsat satellites have been imaging the planet since 1972, compiling an uninterrupted photographic record of more than three decades of natural and human-induced changes to the Earth’s land surface. Landsat imagery is used by scientists and land use planners worldwide, state and local governments, commercial interests and the national security community. Recognizing the importance of Landsat, Congress in 1992 enacted a law, the Land Remote Sensing Policy Act, committing the U.S. government to ensure the long-term continuous collection of Landsat imagery.

The United States has two Landsat satellites on orbit, but neither is expected to last beyond this decade. Landsat 5, launched in 1984, remains operational despite its advanced age, but with no redundant systems on board, it is one component failure away from being useless. In any event, it is expected to run out of fuel before 2010. Landsat 7 is only six years old and has enough to make it into 2010 but has been returning degraded data since its main sensor malfunctioned in 2003. And with one working gyroscope, it too is one failure away from being useless. Because Landsat 7’s degraded imagery is unusable for some applications, Landsat officials acknowledge a data gap already exists for some users.

NASA had once planned to replace Landsat 7 with a commercially operated satellite that would supply that government with all the Landsat imagery it needed.

NASA’s effort to commercialize the collection of Landsat imagery fell apart in 2003 when the agency rejected a proposal from the now defunct Resource 21 — the only bid NASA had received — saying the company’s offer would not have been a good deal for the government.

In response, the White House convened an interagency group of Landsat users to find a solution for ensuring the uninterrupted collection of Landsat data for the long haul. According to participants, the group examined a range of options that included making another attempt at commercialization, forging an international partnership, and funding a government-owned and operated solution.

The group ultimately settled on the government-owned solution, but rather than recommending the building of another dedicated Landsat satellite, it opted for adding a Landsat-type instrument to NPOESS. John Marburger, science advisor to President George W. Bush, issued a memo on Aug. 14, 2004, outlining the NPOESS solution as the centerpiece of the government’s Landsat data continuity strategy.

A former U.S. government official involved in the development of the strategy said the NPOESS solution was selected because it was the best value for the taxpayer. The White House and the interagency group determined that the Operational Land Imager instruments could be developed and added to NPOESS Charlie 1, the first of the planned series of six satellites, and NPOESS Charlie 4, the fourth in the series, and ensure 14 years of continuous data collection for the same or less than what it would cost to build and launch a single dedicated Landsat satellite designed to last seven years.

After the initial instrument development and integration issues were worked out, proponents of the NPOESS solution reasoned, the Operational Land Imager could be added to subsequent weather satellites for even less.

Not only did the free flyer look more expensive, the former government official said, it too would permit a data gap, albeit a shorter one. “There were two problems with doing a bridge mission,” the source said. “It didn’t save you a lot of time and the other was money.”

Gap Filler

While the details of the NPOESS strategy were still being worked out, NASA continued to talk to industry about the possibility of building a free-flying satellite to bridge the projected year or longer gap between Landsats 5 and 7 and the launch of NPOESS Charlie 1.

NASA challenged aerospace contractors to come up with a Landsat-type spacecraft that could be built and launched by 2008 for no more than $300 million. The cost target was aggressive, but not unachievable, industry sources said at the time. Although Landsat 7 had cost NASA more than $800 million to build and launch, the agency has since built and launched the experimental Earth Observer-1 spacecraft and its advanced land imaging instrument for much less.

On the eve of Landsat 7’s launch in 1999, Ghassem Asrar, then NASA’s Earth science chief, told Space News that its successor could be built for $200 million to $250 million thanks to the breakthroughs being achieved on Earth Observer-1. NASA also invested several hundred million dollars in low-cost satellite design studies under its ill-fated Landsat commercialization effort.

Last year, industry told NASA it could build a Landsat-type satellite that fit the bill for under $250 million not including launch. By the time NASA factored in the above market rates it pays for launches and what it would spend on civil servants assigned to oversee the mission, the cost estimate had gone up significantly. Government officials involved in the White House-led interagency group tackling the Landsat issue said NASA reported that a gapfiller Landsat mission would cost around $500 million — more than what the government would have to spend adding land imagers to two NPOESS satellites.

Companies never got a chance to submit formal bids for a gapfiller mission. In late September 2004, NASA sent contractors a so-called request for information on the Landsat gapfiller mission, only to rescind the solicitation later the same day. Word got out that a gap-filler mission was off the table.

When NASA sent its 2006 budget request to Congress in February, it requested no funds for doing the mission, asking instead for the first $54 million of the $250 million it said it would need through 2010 to build the Operational Lander Imager in time to go on NPOESS Charlie 1.

NOAA asked for the first $11 million of the $80 million is said it would need to solve the integration challenges involved in adding the instrument to NPOESS.

Proponents of building a Landsat bridge mission said estimates for building the land imager and adding it to NPOESS are on the rise and threaten to eclipse even NASA’s higher estimate for a gap filler mission. However, they say the strongest arguments for doing a bridge mission are not budgetary, but rather have to do avoiding a big data gap.

NPOESS Has its Own Problems

The push to win approval for a Landsat bridge mission comes as NPOESS is experiencing plenty of problems of its own. The U.S. Government Accountability Office, at the request of the House Science Committee’s environment, technology and standards subcommittee, is initiating its third NPOESS review since 2003. The NPOESS program manager, John Cunningham, surprised colleagues when he announced Aug. 18 that he was resigning his post and leaving government service come mid-September. NOAA spokesman John Leslie said the agency — one of the key players in the interagency program — would “work aggressively to find his replacement.”

NOAA, meanwhile, has been talking with the White House Office of Management and Budget about adding more money to the NPOESS program to address problems relating to three of the satellite systems main instruments.

A senior U.S. government official who works with NPOESS said the program is “back on track” but big questions remain about what it will cost to finish the satellite system. “Right now I lack confidence in all the numbers I am seeing,” the government official said.

Dave Powner, the GAO auditor heading up the recently initiated NPOESS review, told Space News that getting a handle on the program’s cost and schedule is one of his main objectives. He said his team also will be evaluating the effect of adding the Operational Land Imager to the project.

He would not comment on the current review, which he expects to wrap up by March, but said that the GAO’s last look at the program, completed late last year, found that the cost estimate for completing NPOESS had grown to $8.1 billion, an increase of $1.2 billion over the previous estimate . Government officials said the latest cost estimate is even higher, but declined to provide a figure.

Northrop Grumman Space Technology, the El Segundo, Calif-based prime contractor on NPOESS, acknowledged the cost growth and schedule delay, attributing it primarily sensor development issues. But the company also would not say what it will cost to finish the program.

“We have provided all our information to the government,” said Northrop Grumman spokeswoman Sally Koris. “Total impacts to cost and schedule are contingent on how the government chooses to respond. Therefore, until the government decides how to proceed, the cost and schedule impacts are not known.”

Koris, however, said Northrop Grumman still sees NPOESS as an affordable and achievable solution for ensuring the long-term collection of Landsat imagery.

“NPOESS was designed from the start to accommodate new instruments that would be developed,” Koris said, explaining that the satellite has enough room, electrical power, and data-handling capability to accommodate the Operational Land Imager.

Although government and industry sources said the non-recurring engineering costs for figuring out how to accommodate the sensitive land imager aboard the relatively noisy NPOESS bus are going up, Koris said Northrop Grumman is “very confident” that it can add the finished instrument to NPOESS Charlie 1 for $85 million and the Charlie 4 for $25 million.

In contrast, Koris said, single free-flying spacecraft “could be conservatively estimated at $250 million or more” not including the cost of the instrument itself or the launch and would only provide half service life as NPOESS. Koris said Northrop Grumman is “very confident” that it can accommodate the finished land imagers

Proponents of doing a free-flying Landsat gapfiller said one of the reasons instrument development and integration costs are so high for NPOESS is because the spacecraft presents a less than ideal platform for carrying out the Landsat mission For starters, Landsat and NPOESS satellites fly at different altitudes, raising calibration issues. NPOESS’ five other instruments produce substantial vibration and jitter, creating problems for a sensitive camera like the land imager, they said.

Even if the integration issues can be worked out, and even gapfiller advocates concede they probably can give enough time and money, critics say the Operational Land Imager would have more restricted field of view than it would on a free flyer and would have to compete with operational weather instrument for data down link time.

Koris said Northrop Grumman has studied these issues and concluded that the Operational Land Imager can perform its mission on board NPOESS. She also said NPOESS features a robust data downlink and distribution system that can accommodate all instruments and users. “Nobody is going to be waiting for data,” she said.