WASHINGTON (Reuters) - Four months after the newest U.S. missile-warning satellite built by Northrop Grumman Corp failed in orbit, officials are still investigating what happened.
The classified Defense Support Program satellite known as DSP 23 was launched into geosynchronous orbit in November 2007 but stopped responding to commands in mid-September last year, as first reported by Reuters in November.
“There’s not that much data available,” one U.S. defense official said, describing the current investigation as sophisticated, long-distance detective work.
“You have to go back and recreate what might have been going on,” said the official, who asked not to be named because he was not authorized to speak about the program. There may never be “great certitude” about what went wrong, he added.
Defense officials say possible causes for the failure range from defective parts or software problems, a natural phenomenon like a solar flare, or possibly, although unlikely, debris in space. An intentional attack was also possible, but very unlikely, they said.
Citing concerns about a toxic fuel tank, the U.S. government last February shot down a smaller classified satellite that failed due to software problems almost immediately after being launched into orbit in December 2006.
As a result of those software concerns, Lockheed Martin Corp was forced to rewrite code for its Space Based Infrared Satellites (SBIRS) that will succeed the DSP program.
It was not clear if similar software issues could be behind the latest satellite failure, but officials said that possibility was being closely investigated.
Northrop declined to comment on the September failure, referring questions to the U.S. Air Force, which owns and operates the satellite. Air Force officials declined to comment.
The U.S. government has launched 23 of Northrop’s DSP missile-warning satellites since 1970. Two failed to reach orbit and experts estimate that seven are still working, about twice the number needed to watch the entire Earth at once.
The September failure of the newest DSP satellite raises the possibility that the United States may have gaps in its ability to detect enemy missiles in the future, unless new satellites are launched soon, said analyst Loren Thompson.
“Everybody expects the oldest satellites to fail, but when you lose your newest satellite, you’re taking years off the tail end of how long the constellation is going to be effective,” said Thompson, of the private Lexington Institute.
The first two of Lockheed’s SBIRS sensors are in orbit on board other satellites, but the first dedicated satellites are not due to be launched until 2010.
Lockheed’s SBIRS program began in 1996 with the aim of launching the first satellites in 2004 at a cost of $4.2 billion. The program has been restructured several times and its price tag is now seen at well over $11 billion.
A second defense official, who also asked not to be named, said existing DSP satellites made by Northrop were functioning well and had a “reasonable probability of remaining OK.”
But he acknowledged that the U.S. military preferred higher levels of redundancy in such critical systems, and agreed that the September failure raised the prospect of a gap in coverage, especially if other satellites failed prematurely.
“Although we have generally done well, spacecraft do get older and sooner or later they fail, or we take action to get them out of the way,” said the official, who was not authorized to speak about the satellite program.
The Pentagon has already asked Congress for $117 million this fiscal year for a new satellite to hedge against a potential gap in satellite coverage around 2014.
But the first defense official said he was not convinced about the urgency of the risk and said some might be using the latest satellite failure to secure additional funding for space programs in an increasingly difficult budget environment.
Several other military space programs focused on improving communications have had their budgets curtailed sharply in recent years by lawmakers and defense officials after encountering technical problems and cost overruns.
Budget pressures may grow even more severe in coming years, given expensive financial bailouts and mounting bills to replace equipment worn out in Iraq and Afghanistan.
Both officials said they were concerned that the incoming Obama administration would not make military space programs a big priority, given their high cost and past problems.
Reporting by Andrea Shalal-Esa; Editing by Tim Dobbyn