NOAA on Monday began moving a backup weather satellite into position to replace an observatory knocked out of service in September by an unexplained problem with its atmospheric imaging and sounding instruments.

Animation of GOES 14's movement into an operational orbital position. Credit: NOAA

Controllers commanded the GOES 14 satellite to drift from its standby position in geostationary orbit at 105 degrees west longitude toward the location of GOES 13, which ceased weather observations Sept. 23, according to NOAA, the U.S. government's weather agency.

The GOES 13 satellite, stationed over the equator at 75 degrees west longitude, began showing noise in imaging and sounding data earlier in September. NOAA placed the satellite in standby mode Sept. 23 to allow engineers to investigate the problem.

According to NOAA, GOES 13 is otherwise healthy and remains stable. GOES 13 launched in 2006 and was designed for a 10-year life.

NOAA's Geostationary Operational Environmental Satellite, or GOES, system consists of two spacecraft to cover the Western Hemisphere. One satellite over the Pacific Ocean is in the GOES West position, and another observatory in the GOES East location covers the Atlantic Ocean.

GOES 13 is parked in the GOES East position.

The GOES 14 satellite, which was an in-orbit spare at 105 degrees west, assumed regular observations of the U.S. East Coast and the Atlantic Ocean shortly after GOES 13 was deactivated.

On Monday, GOES 14 fired rocket thrusters to begin drifting east along the equator toward the GOES East position.

"While engineers continue to find the cause of GOES 13's trouble, it will be sent to [a] registered spare position in orbit," NOAA said in a press release. "Meanwhile, it will take approximately 33 days to shift GOES 14 from its current position to the GOES East location."

Shifting GOES 14 further east will allow the satellite to see more of the Atlantic Ocean.