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The fifth Mobile User Objective System (MUOS-5) communications satellite experienced a “failure” in its orbit-raising propulsion system while being transferred from its initial orbit to its final orbit June 29, the U.S. Navy said Aug. 2.
“The satellite remains in a stable intermediate orbit since experiencing the anomaly,” the Space and Naval Warfare Systems Command (SPAWAR) said in a statement. “The MUOS team is continuing to evaluate the situation, considering alternate orbit adjustment options, calculating mission impact and investigating all options before proceeding.”
Photo: Lockheed Martin
The announcement came several weeks after the Navy revealed that the Lockheed Martin-built [LMT] satellite had experienced an unspecified “anomaly” during the transfer. MUOS-5 lifted off aboard a United Launch Alliance (ULA) Atlas 5 rocket on June 24 and was projected to enter its test location 22,000 miles above Hawaii by July 3. But the anomaly forced the transfer maneuver to be halted at least temporarily.
MUOS-5 was launched as a spare for the new MUOS constellation, whose first four satellites provide ultra-high-frequency satellite communications for military operations. MUOS is designed to provide near-global, smartphone-like communications for mobile military forces, including aircraft, ships and ground troops. It is intended to eventually replace the aging Ultra High Frequency Follow-On (UFO) satellite system.
