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Delta rocket flies on 5th launch try

Irene Klotz, Spaceflight Correspondent
Jul 29, 2014, 8:29 UTC

Sen—Taking advantage of a break in Florida’s stormy summertime weather, a United Launch Alliance Delta 4 rocket bolted off its seaside launch pad Monday to deliver a trio of satellites into orbit for the U.S. Air Force.

The rocket lifted off at 7:28 p.m. EDT (2328 GMT) from Cape Canaveral Air Force Station. Poor weather scuttled three previous launch attempts last week. Problems with ground support equipment canceled the first launch try on July 23.

The rocket carries a pair of satellites that will be positioned to keep tabs on the hundreds of spacecraft in geosynchronous orbit about 22,300 miles above Earth.

The so-called Geosynchronous Space Situational Awareness Program, or GSSAP, was partially declassified in February.

The program "will bolster our ability to discern when adversaries attempt to avoid detection and to discover capabilities they may have which might be harmful to our critical assets at these higher altitudes," General William Shelton, head of Air Force Space Command, said in a speech.

He compared GSSAP to a “neighborhood watch program.”

The rocket also carries a small experimental spacecraft named ANGELS, an acronym for Automated Navigation and Guidance Experiment for Local Space. It will use the region around the now-discarded Delta 4 second-stage engine to test sensors and technologies for future space surveillance satellites.

“Essentially we need to know what’s in orbit, its purpose and its intent. ANGELS is a science and technology project developing sensor and navigation technology, plus the honing of operational techniques, providing new ways to examine what is in geosynchronous orbit,” said Daniel Knappmiller, a captain at Air Force Research Laboratory's Space Vehicles Directorate, located at Kirtland Air Force Base, N.M.

“Many of our military and key commercial communication satellites orbit in GEO (geosynchronous equatorial orbit) … making it difficult to discern the purpose of a given object from existing ground-based telescopes, for instance.

"With space becoming more contested and congested, enhancing our situational awareness in GEO is increasingly crucial,” Knappmiller said in an interview during United Launch Alliance’s live launch webcast.

ANGELS’ test region will be several hundred kilometers above GEO, beginning about 50 km away from the Delta 4 second stage. Over several months, it will navigate to within several kilometers of the rocket body, he added.

The Air Force is less forthcoming about operational aspects of the GSSAP program and satellites.

“The GSSAP satellites will provide U.S. Strategic Command with space situational awareness data allowing for more accurate tracking and characterization of man-made orbiting objects,” the Air Force said in a press release.

“Data from GSSAP will uniquely contribute to timely and accurate orbital predictions, enhancing our knowledge of the geosynchronous orbit environment, and further enabling space flight safety to include satellite collision avoidance,” the Air Force said.