Geostationary Satellites - Scanning Strategies

GOES E and W scan in two modes:

1) routine mode -

• In the routine mode, a full disk of the earth is scanned once every 3 hours.
• The total time to scan the full disk is about 18.2 minutes.  The satellite scans in the east-west direction, starting at the north pole and working down to the south pole.  Scan lines look like this.   The scan mirror in the imager steps down (south) by 0.011° for each scan so subsequent scan lines are displaced further south.  To scan the full disk, 1821 scans are required taking about 18.2 minutes to complete.  The time stamp on the image is the time the scan sequence was started.   

• Contiguous US (CONUS) is scanned eight times per hour to monitor rapidly developing storms.
• However, the satellites can scan in the rapid scan mode, providing imagery over a smaller area every one minute!! 

Data from both GOES E and W are transmitted to Wallops Island, VA.

• Check out the up-to-date scan schedule at the NOAA GOES web site:  http://www.oso.noaa.gov/goes/schd-sector/index.htm