Incredible Image of Earth Taken on 12/13/14
Adam Rifkin stashed this in Astronomy Pics
From the NASA GOES satellite.
Great Reddit comment:
It is not quite as composite as one might think. It is produced by GOES-11 and GOES-12 missions (Geostationary Operational Environmental Satellite), which sit over the same spot and continuously monitor the earth, so this is pretty much what the earth looks like from their perspective. Any artifacts (such as the one near the amazon river) are likely from the scanning action of the primary imaging sensor, which scans in north-south lines from west to east. The scanner doesn't just scan the whole earth over and over, but can focus in on specific storm systems, which means data coverage is not constant over the entire observation area.
For more resources than you probably wanted, check this out: http://goes.gsfc.nasa.gov/text/databook/databook.pdf
or the home page: http://goes.gsfc.nasa.gov/