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Missions: A-Train
NASA and its international partners operate several Earth-observing satellites that closely follow one after another along the same orbital “track.” This coordinated group of satellites, constituting a significant subset of NASA’s current operating major satellite missions, is called the Afternoon Constellation, or the A-Train, for short. The satellites are in a polar orbit, crossing the equator northbound at about 1:30 p.m. local time, within seconds to minutes of each other. This allows near-simultaneous observations of a wide variety of parameters to aid the scientific community in advancing our knowledge of Earth-system science and applying this knowledge for the benefit of society. Six satellites currently fly in the A-Train: GCOM-W1, Aqua, CALIPSO, CloudSat, PARASOL, and Aura. On November 16, 2011, PARASOL was lowered to 9.5 km under the A-Train and continues its nominal mission observing clouds and aerosols. OCO-2 is scheduled to join the configuration in 2014.
| Mission | Mission Category | Status | |
|---|---|---|---|
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Aqua | Current, Extended Mission | |
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Aura | Current, Extended Mission | |
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Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) | Completed | |
 |
CloudSat | Completed | |
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Glory | Launch Failure | |
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Orbiting Carbon Observatory 2 (OCO-2) | Current, Extended Mission | |
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Polarization & Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar (PARASOL) | Completed | |
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The Global Change Observation Mission-Water (GCOM-W1) | Extended Mission |