The live earth photo collections have been used mostly by governments, scientists and educators so far. Monitoring changes in the earth's surface, changes in vegetation, tracking oceans and rivers, rising or falling water levels, and various other scientific and geographic applications are all areas where live earth photos have proven extremely valuable. Agriculture and national defense are two areas of study that are now almost completely reliant upon live earth photography. Aside from the obvious scientific uses, hundreds of thousands of casual online observers may be the biggest single group of people enjoying the views of live earth photos today.
Some of the largest and most popular live earth photo image resources available online are Google Earth and NASA. Google Earth maintains an updated online gallery of thousands of high quality earth images. It offers a free service that allows users to "fly" anywhere on Earth and view satellite imagery, maps, and more. Google Earth lets users explore places on earth seldom, if ever, seen before and share the views they find with others. Back in its' infancy, Google Earth was originally called EarthViewer 3D. Today, Google Earth maps the planet with satellite imagery, aerial photography and 3D programs. Google Earth is available in a free version and a "commercial use" version called Google Earth Pro that costs $400 per year.
The Gateway to Astronaut Photography of Earth was created with public dollars by the National Aeronautics and Space Administration (NASA) and is another fantastic place to view live earth photos. The Gateway website features the most complete collection of photography of the earth from the early 1960's, all the way up to the most recent digital photographs that are downloaded every day from the International Space Station flying thousands of miles above the planet. The database contains over a million images with new data being added daily.
All of the Gateway to Astronaut Photography of Earth web pages are maintained by NASA's Johnson Space Center. The site includes free search tools for viewing digital images on the Web. Some of the tools offered include clickable all-earth maps, custom searches by image number, and complete searches of all available NASA photography databases. Some of the special collections include groups of both large and small cities, the best photographs from particular missions, and captioned photo sets packaged for educational uses. The NASA Gateway site also features articles and features explaining the science behind astronaut photography of earth and how it is used in a variety of scientific, governmental and civilian applications.