This page was created as a resource for various types of remotely sensed data. I prefer federal and state provided data, but some privately controlled data is acceptable as well. This data is incredibly useful in all sorts of geospatial analysis including landcover analysis, spatial statistics, and other assorted types of digital image processing.
- GLOVIS - The USGS Global Visualization Viewer, run by the Earth Resources Observation and Science Center of USGS. This is probably the best source of remotely sensed data I've come across. Data is freely downloadable, provided you create an account, and there is a lot of it. NAPP, NHAP, Landsat, MODIS, Aster, etc.
- NC OneMap - The site sort of sucks, but the state of NC provides a lot of good geographic data for free here, including up to date corrected orthophotos, which is what I mainly use it for.
- NOAA GOES - The Geostationary Satellite Server, run by NOAA. These guys maintain several satellites that are in locked orbit with various parts of the earth. Great for analyzing infrared, visible light, and water vapor data over various parts of the states.
- The Gateway to Astronaut Photography of Earth - Lots of great images in here. Some aren't so great for typical remote sensing applications, but they are very pretty. They also have a lot of night photography.
- http://landsat.org/ - The same imagery can be found on glovis, but this has a different tool for selecting it.
- Global Land Cover Facility - These guys have a lot of imagery: ASTER, Ikonos, Quickbird, landsat, MODIS, SRTM, and Orbview. They only have imagery for certain areas, but they do have imagery for non-US locations.
- NASA's JPL Radar Imaging Page - A lot of this is outdated, but it's a great resource for information about radar imaging.
- USGS EarthExplorer - Very similar to glovis, but with a considerably nicer user interface.
- USGS National Map Viewer - A great place to go for all sorts of geographic data. Includes a mix of vector and raster data. Can be confusing to use at times, but generally provides great data.
- USGS CLICK - Center for LIDAR Information Coordination and Knowledge.
- Gmap4 - Not particularly special remotely sensed data, but a very powerful web application for examining GPS data (or any other shapefiles, within reason) overlaid on Google's maps and remote sensed data, as well as very high quality USGS 1:24k quads.