The U.S. Defense Department used an experimental satellite to observe the launch of a target missile Aug. 23 in an exercise that could assist the development of future missile tracking satellites, according to a Missile Defense Agency (MDA) news release.

The Aug. 23 exercise was the first of two such demonstrations planned for the Near Field Infrared Experiment (NFIRE) satellite, which was launched into orbit in April. The target in the test was a modified Minuteman 2 missile that was launched from Vandenberg Air Force Base in California.

The NFIRE satellite, which was built by General Dynamics Advanced Information Systems of Gilbert, Ariz., used an infrared sensor to gather high- and low- resolution imagery of the Minuteman 2 missile as it passed within 3.5 kilometers of the spacecraft, according to a General Dynamics news release issued

Aug. 23.

“The success of NFIRE is important to the development of missile defense technologies that will be used to defend the United States,” said David Shingledecker, vice president and general manager of integrated space systems for General Dynamics. “We’re pleased that our flexible spacecraft design helps to enable this unique mission.”

The data gathered in the exercise was downlinked to the Missile Defense Space Experimentation Center at the Missile Defense Integration and Operations Center at Schriever Air Force Base in Colorado. It

is intended to help

MDA develop infrared sensors for future missile warning and tracking satellites like the Space Tracking and Surveillance System. Those sensors are supposed to

discriminate between a

missile body and its fiery exhaust plume.

The data

also is intended to aid in

the development of the guidance, navigation and control systems for future missile defense interceptors, according to MDA officials.

MDA previously had attempted to conduct the test Aug. 17 and then again Aug. 21, but postponed it twice after officials were unable to resolve software issues with the NFIRE spacecraft that resulted in error messages during pre-mission communications, according to an MDA official.

The exercise cost about $25 million, which primarily covers the cost of the Minuteman 2 missile as well as range expenses, the official said.

A second NFIRE demonstration, again with a modified Minuteman 2 missile, is expected to be conducted in mid to late October, the official said. The total cost of the program is $300 million, the official said.

The initial plans for the NFIRE satellite included an additional sensor mounted on a kill vehicle used with missile defense interceptors. That sensor would have been launched from the NFIRE satellite and flown in close proximity to the target missile to take a closer look

. MDA officials later acknowledged that it would have likely unintentionally struck the target missile.

That concept raised concern amongst Democrats in Congress and critics opposed to the concept of space-based missile interceptors and anti-satellite weapons, who charged that the NFIRE demonstration was intended to lead toward the development of such systems.

MDA scrapped plans for the kill vehicle in 2004, and added a laser communications payload built by Tesat-Spacecom GmbH & Co. KG in its place. The communications payload will be used in experiments following the second NFIRE exercise with a missile to demonstrate both satellite-to-satellite and satellite-to-ground communications, according to the General Dynamics news release.

MDA officials have said that the testing with the German payload could help them explore the benefits of using laser communications links on future missile tracking satellites to transmit data faster,

enabling satellites to gather and distribute more data to improve the probability of successful intercepts.

While several Republican members of Congress, including Rep. Terry Everett (R-Ala.)

, ranking member of the House Armed Services strategic forces subcommittee, have advocated for the construction of a second NFIRE spacecraft that would include a kill vehicle to pave the way for the development of space-based missile interceptors as well as anti-satellite weapons, MDA has no plans to do so at this time, the MDA official said.