Very detailed update on falling satellite

Falling Radar Satellite Adds to NRO Troubles

Feb 3, 2008

By Craig Covault

The Boeing-National Reconnaissance Office imaging radar spacecraft that failed shortly after launch creating a falling debris risk indicates that trouble within the NRO Future Imagery Architecture (FIA) program has spread to the radar side of the highly secret project.

The debris could impact anywhere between 58.5 deg. N. and S. Lat. in late February or early March.

Some analysts believe the debris could reveal national security secrets if not recovered by members of the NRO/Pentagon teams being formed to travel to the impact area should it land on North America or other friendly territory.

Others more familiar with the actual hardware do not believe, however, that the debris will poses a security risk. Air Force Gen. Victor E. (Gene) Renuart, Jr., who heads U.S. Northern Command, told the Associated Press that there does not yet appear to be much concern about sensitive technologies on the satellite falling into enemy hands. “I’m not aware that we have a security issue,” he says. “It’s really just a big thing falling that we want to make sure we’re prepared for.”

Reentry debris analysis from the space shuttle Columbia accident is being applied to Pentagon assessments on how much of the failed NROL-21 imaging radar will survive reentry and strike Earth.

The Defense Dept. and especially the U.S. Northern Command have been forming debris recovery teams and making other preparations for months, ever since the spacecraft failed minutes after launch from Vandenberg AFB, Calif., on Dec. 14, 2006, on a United Launch Alliance Delta II.

This week marks the fifth anniversary of intensive Columbia debris recovery, mostly in Texas, following the Feb. 1, 2003, reentry accident that resulted in the loss of the orbiter and its seven-member U.S.-Israeli crew. The resulting debris has been made available to researchers over the last several years for analysis into the types and amounts of spacecraft materials that can survive reentry and strike the ground. That data is now being used operationally for the first time by the Pentagon, NASA and NRO analysts to better calculate how much debris will plunge through the atmosphere.

From a U.S. reconnaissance standpoint, the FIA optical recon program was rife with problems long before the FIA radar development satellite failed.

As the NRO, Pentagon and Boeing continue to bungle what, under FIA, were supposed to have been faster, cheaper, better optical and radar-imaging spacecraft, countries such as China are moving ahead with large military programs that are increasingly difficult to monitor with dwindling U.S. reconnaissance assets.

FIA program foul-ups had already cost Boeing and the NRO several billion dollars on the optical side. The optical spacecraft design was so flawed that NRO removed Boeing and assigned the project to Lockheed Martin (AW&ST Sept. 26, 2005, p. 30). That contractor had been making highly successful, but expensive, Advanced KH-11-class spacecraft for 25 years when Boeing won the FIA contract for both radar and optical satellites. Analysts now believe that Lockheed Martin is working on two Advanced KH-11 gap filler spacecraft for about $15 billion to replace the delayed FIA systems.

Smaller companies like Colorado-based DigitalGlobe and GeoEye of Virginia are also likely to be involved in a different competition to develop more classified versions of smaller optical spacecraft like WorldView-1 that was also recently launched by a Delta II at Vandenberg. The DigitalGlobe WorldView-1 civil/military spacecraft is providing extraordinary 18-in. image resolution from about 300-mi. altitude (see photo below, right). The first competing GeoEye spacecraft is set for launch from Vandenberg in August—in what will be one of the military space programs most important launches of 2008. Both the DigitalGlobe WorldView program and GeoEye effort are part of the $1-billion NextView program managed by the National Geospatial-Intelligence Agency, a key intelligence community organization.

There is also a program code-named “Basic” that might or might not be related to the Lockheed reconstitution of Advanced KH-11 type assets.

If the NROL-21 mission failure has caused management shakeups, NRO and Boeing have kept them secret.

Fortunately, the much different NRO eavesdropping signals intelligence satellite fleet seems to be faring better with new designs. It too is facing a major test this month at Vandenberg.

The new NROL-28 mission, a large eavesdropping sigint spacecraft, is set to launch Feb. 26 into a highly elliptical orbit on board the first Atlas V Evolved Expendable Launch Vehicle to be flown from Vandenberg. Such sigint spacecraft have proved important in tracking Al Qaeda and in searching for Osama Bin Laden.

The launcher for NROL-28 will be an Atlas V-411 version, with a large 4-meter fairing, one strap-on booster and a single-engine Centaur upper stage, This is also an important Vandenberg mission because it will also carry, as a piggyback payload, just the second Sbirs Highly Elliptical Orbit (HEO) sensor. The NROL-28 Sbirs missile-warning sensor will be tested with another that has been aloft for about 18 months also on board an NRO sigint host spacecraft. The NROL-28 mission is also unusual because it will carry two small NASA subsatellites.

The U.S. for nearly 20 years has operated mammoth Lacrosse space-based radars—the last of which are aging in orbit.

Placing the development of new radar imaging satellites under the FIA program was done with the hope that smaller, less-expensive radar imagers may result.

Doing the same with optical spacecraft failed, and with the NROL-21 mission loss, the radar program now must also recover, although it is being left under Boeing control.

Reconnaissance to follow Al Qaeda activity in mountainous terrain is one important mission—especially for radar spacecraft. The radars can differentiate camouflaged trucks or pack animals in mountainous terrain or under trees. They can also see just fine at night and through clouds.

The identification of NROL-21 as a radar mission has only recently come about by analysts at organizations like Global Security.Org. Independent analysts like Canadian Ted Molczan have also noted the spacecraft was launched into a “frozen orbit”—an orbit with characteristics like that used by most all previous radar satellites be they military or civilian.

The Air Force has assigned the highest possible radar monitoring of the falling satellite. And, closer to the reentry date, the Defense Support Program (DSP) infrared missile warning satellites along with the new Sbirs high Earth-orbit sensor will begin to look for an increased infrared signature from the satellite as friction with the upper layers of the atmosphere begins to heat it up. Pentagon ground facilities with infrared capability like one sited on a Maui, Hawaii, mountaintop will also begin to image the spacecraft. It has probably done so several times already.

While this is underway the U.S. is contacting other governments worldwide about the impending reentry. U.N. treaty provisions also cover such events.

China and Russia present two of the largest areas for a potential impact. It is unlikely, however, that debris recovery teams would be allowed to operate in those countries. Were an impact to occur, China will probably issue protests about the U.S. “militarizing space.”

The spacecraft will break into little pieces. Most of the satellite will burn up, but some extremely lightweight pieces or extremely dense materials will survive the reentry and fall within an ellipse that cannot yet be determined this far ahead of impact.

Several tens of pounds of spacecraft debris could reach the ground. The orbit overflies all of the world’s most populated areas. But the debris statistically is far more likely to land in an ocean, since water underlies more than 90% of the ground track.

Details emerging from the program indicate that the satellite is relatively small.

Contrary to media reports that say the spacecraft is as large as a school bus weighing up to 20,000 lb., the failed satellite is actually one of the smallest launched in the last several years by the NRO.

The spacecraft’s main body is no more than about 15 ft. long X 8 ft. wide, and likely even smaller than that. Had its large radar dish been unfolded in orbit the vehicle would have been the size of a basketball court. But anything deployed would have been extremely lightweight compared with the central core, which houses the propellant tanks, momentum wheels, gyros and avionics boxes. The top-secret radar antenna is extremely fragile, and is the most likely component to burn up entirely by reentry heating.

The spacecraft’s size is actually the most easily calculated parameter of the secret satellite, since it was launched on board a United Launch Alliance Delta II booster. Delta IIs have small payload shrouds measuring only about 16 X 10 ft. And the satellite would not consume the entire dimensions of the shroud, analysts point out.

Pentagon managers knew within days of the launch more than a year ago that they were going to face a major space debris incident. But at the time most news outlets took no interest in the Vandenberg NRO launch—allowing the significance of the radar, and now its debris impact, to go unnoticed publicly for more than a year.

The satellite was launched into an initial 351 X 367 km. (218 X 228 mi.) orbit inclined 58.5 deg. Orbital drag has now reduced that to 271 X 282 km. (168 X 175 mi.) with the satellite descending 2,310 ft. per day, according to Molczan.

A National Security Council official says that some of the debris could involve hazardous materials. The satellite is not nuclear-powered so there should be no risk from radioactive materials, although some spacecraft do carry tiny plutonium-powered heaters, but these would not pose a debris hazard.

The greater danger will be from any hydrazine propellant residue that does not fully burn up on reentry.

The spacecraft’s hydrazine tanks are full of maneuvering propellant and past experience with both Columbia and smaller spacecraft indicates that hollow lightweight propellant tanks can survive reentry and reach the ground along with heavier components like momentum wheels.
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