Rocket launch sends communications satellite into space
A heavyweight Navy communications satellite was boosted into space by a United Launch Alliance Atlas 5 rocket Friday, the second in a series of five relay stations that will act like orbital cell phone towers in a globe-spanning $5 billion network.
The second Mobile User Objective System satellite -- MUOS-2 -- tipped the scales at nearly 15,000 pounds, making it one of the heaviest payloads ever launched atop an Atlas 5, requiring five solid-fuel strap-on boosters to generate the required lift.
The 206-foot tall rocket roared to life at 9 a.m. -- 12 minutes late because of high upper level winds -- and and quickly accelerated away from launch complex 41 at the Cape Canaveral Air Force Station, reaching the speed of sound in just 34 seconds as it arced away to the east over the Atlantic Ocean.
The strap-on boosters fell away as planned about a minute and 45 seconds after liftoff. The Atlas first stage and its Russian-built RD-180 engine fell away four minutes and 27 seconds after launch and the flight continued under the power of a Pratt & Whitney RL10 Centaur second stage engine.
Three Centaur firings were required over three hours to boost the satellite into the required elliptical transfer orbit. The satellite's on-board propulsion system will be used over the next week or so to raise the low point of the orbit, putting MUOS-2 into a circular orbit 22,300 miles above the equator.
Another three days will be needed to unfurl the relay station's solar arrays and antennas.
Built by Lockheed Martin, the MUOS communications system will be made up of four satellites and one spare, eventually replacing the Navy's Ultra High Frequency Follow-On spacecraft.
Each satellite is equipped with a pair of gold mesh antennas. A 17-foot-wide antenna will service ground terminals that currently send voice and data to older UHF comsats. The other, measuring 46 feet across, will provide faster, cellular-network-type communications.
"MUOS will deliver unparalleled high-speed communications access to mobile users for decades," Iris Bombelyn, an executive with satellite-builder Lockheed Martin, told reporters before launch.
"The MUOS satellite provides not only ongoing support for the legacy UHF Follow-On users in the field but a myriad of new services, bandwidth, capacity and applications to mobile users."
The new satellites provide what amounts to a 3G-like cellular telephone network.
"The architecture that we've built with the satellite constellation and with the global ground network, the satellite is the cell tower," said Navy Capt. Paul Ghyzel, manager of the Satellite Communications Program Office.
"Anybody (who) is using a radio that is capable of communicating with MUOS, when they speak, their transmission is picked up by the satellite and then routed like a cellular system would route to wherever it needs to be to talk to the guy on the other end."
The satellites can be used for direct relay -- a user in Hawaii, for example, could call a ship 200 miles off shore using a single satellite -- or to relay a call to another satellite for users farther away.
"If that ship commander needs to talk to somebody that is in Afghanistan, then they are going to transmit over MUOS, the satellite over the Pacific is going to up that transmission, but (it is) then routed through the rest of the MUOS network to the satellite that's going to be over the Indian Ocean, eventually, and then down into Afghanistan," Ghyzel said.
"You can think of the satellites as the cell towers in the sky. That's a really good way to think of how the system works."
This was the 39th flight of an Atlas 5, the fifth so far this year and the fourth using five strap-on boosters.
