The first in a new class of Tracking and Data Relay Satellites arrived at NASA's Kennedy Space Center in Florida on Dec. 18 to begin the final phase of launch preparations ahead of a targeted liftoff on Jan. 29, 2013.

The spacecraft features two large solar arrays, a pair of large antennas and numerous other communications antennas and electronics. It was built at The Boeing Co.'s El Segundo, Calif., facility.

Packaged inside a robust box for shipping, the satellite will be checked out and put into its final configuration for launch atop a United Launch Alliance Atlas V rocket.

TDRS-K, as the new satellite is named, will serve as a communications platform between numerous spacecraft and ground stations on Earth. Its launch will mark the latest upgrade for the sophisticated constellation of spacecraft.

Two more spacecraft, TDRS-L and -M, will launch later in 2013 and 2015, respectively, to complete the upgrade. Stationed in geosynchronous orbit about 22,300 miles above Earth, the satellites can pick up signals from lower orbiting spacecraft and send those signals to ground control and data collection stations.

The International Space Station is a frequent user of the TDRS system. NASA's Hubble Space Telescope and other space-borne observatories also transmit signals through the TDRS satellites.

NASA launched nine TDRS spacecraft, and seven remain active. Two others have been retired. The second TDRS was lost in 1986 during the space shuttle Challenger accident.