Geostationary Operational Environmental Satellite - Satellites

Satellites

Four GOES satellites are currently available for operational use:

• GOES-12 is designated GOES-South, currently located at 60°W .
• GOES 14 is designated GOES-East due to technical difficulties with GOES-13. It was placed in orbit on 7 July 2009, underwent Post-Launch Testing until December 2009 and then was placed in on-orbit storage at 105° W.
• GOES 15 is designated GOES-West, currently located at 135°W over the Pacific Ocean.

Several GOES satellites are still in orbit, either inactive or re-purposed. GOES-3 is no longer used for weather operations, but is a critical part of the communication links between the United States and Amundsen-Scott South Pole Station. Geostationary satellites cannot ordinarily be seen at all from the poles, but they require station keeping fuel to keep them stationary over the equator. When station keeping fuel runs out, solar and lunar perturbations increase the satellite's inclination so that its ground track begins to describe a figure-8 in the north-south direction. This usually ends the satellite's primary mission. But when the inclination is high enough, the satellite may begin to rise above the polar horizons at the extremes of the figure-8, as is the case for GOES-3. A nine-meter dish was constructed at the station, and communication with the satellite is currently possible for about five hours per day. Data rates are around 2.048 Mbit/s bi-directional under optimum conditions.

GOES-8 (GOES-East when it was in operation) is in a parking orbit, currently drifting about 4°W daily. It was decommissioned on April 1, 2003, and deactivated on May 5, 2004, after the failure of its propulsion system.

Communication was lost for 13 days to GOES-12 on December 4, 2007 when it performed a standard station-keeping maneuver. GOES-11 initially took "full disk" images to cover the lost data until a contingency plan could be implemented. On December 5, 2007, GOES-10 was moved from South America operations to temporarily replace GOES-12 as the GOES-EAST operational satellite. On 9 December, communication with GOES-10 was also temporarily lost, but communication was resumed via a backup antenna. GOES-12 was successfully reactivated and moved back to normal operation following a thrust maneuver on 17 December. The trouble was traced to a leaking thruster valve, which pushed the satellite incorrectly. Emergency procedures were executed to cut off the valve, and a redundant thruster was activated to restore the location of the satellite.

GOES-10 was decommissioned on December 2, 2009 and was boosted to a graveyard orbit. It no longer had the fuel for required maneuvers to keep it on station. It joins GOES 8 and 9 which are already in graveyard orbits. With the cessation of GOES-10's duties, GOES-13 has replaced GOES-12 as "GOES-East". GOES-12 was then moved to 60° W and resume South American duties for GOES-10.

GOES-11 had a partial failure 6 Dec 2011, was decommissioned on 16 Dec 2011 and was boosted into a graveyard orbit. GOES 15 was moved to 135° W as GOES West.

GOES-13 is currently out of service due to technical difficulties. It was previously designated GOES-East, and is currently located at 75°W. It provided most of the U.S. weather information.

• GOES-12 visible light image.

• GOES-12 water vapor image.