3rd Place: Meandering Mississippi Landsat 7 Acquired 5/28/2003, Small, blocky shapes of towns, fields, and pastures surround the graceful swirls and whorls of the Mississippi River, the largest river system in North America. Countless oxbow lakes and cutoffs accompany the meandering river south of Memphis, Tennessee, on the border between Arkansas and Mississippi. › Larger image Photo: NASA's Goddard Space Flight Center/USGS
I was pretty sure my favorite picture was the bird's eye view of the aqua swirls, oxbows, and whorls of the Mississippi River cutting into the square tan, forest, and brown patches of farmland south of Memphis, Tennessee. Then I saw the runs of flourescent green phytoplankton flowing like brush strokes around the island of Gotland in the Baltic Sea. Maybe this is the best picture, I wondered? A lot of other people thought so. The public voted it to be the most popular image taken from space via the Landsat series of observation satellites, but it's hard for me to pick a favorite.
1st Place: Van Gogh From Space Landsat 7 Acquired 7/13/2005, In the style of Van Gogh's painting "Starry Night," massive congregations of greenish phytoplankton swirl in the dark water around Gotland, a Swedish island in the Baltic Sea. Population explosions, or blooms, of phytoplankton, like the one shown here, occur when deep currents bring nutrients up to sunlit surface waters, fueling the growth and reproduction of these tiny plants. › Larger image Photo: NASA's Goddard Space Flight Center/USGS
The satellites, which went into operation in 1972, are used by NASA and the USGS to understand land use and natural resource changes caused by people and natural processes. To celebrate the 40-year anniversary of so many pictures of earth from above, the USGS put 120 of them online so the public could vote on their favorites. They colored some for added effect and called them "Earth as Art." You can view the five winners in this post, but don't restrict yourself to just those. Go to the original list, pick out your favorites, and download them as screensavers.
5th Place: Lake Eyre Landsat 5 Acquired 8/5/2006, The scary face in this image is actually inundated patches of shallow Lake Eyre (pronounced "air") in the desert country of northern South Australia. An ephemeral feature of this flat, parched landscape, Lake Eyre is Australia's largest lake when it's full. However in the last 150 years, it has filled completely only three times. › Larger image Photo: NASA's Goddard Space Flight Center/USGS
There are plenty of landscapes with weird color palattes to choose from, including the greens and oranges of the rugged mountains on the border of Pakistan and Afghanistan, the sharp white of the the sea ice near Baffin Island that mimics a galaxy as it spreads out over a dark blue sea, and the dusky reds and golds of the Saharan sand dunes in southwestern Algeria.
4th Place: Algerian Abstract Landsat 5 Acquired 4/8/1985, What look like pale yellow paint streaks slashing through a mosaic of mottled colors are ridges of wind-blown sand that make up Erg Iguidi, an area of ever-shifting sand dunes extending from Algeria into Mauritania in northwestern Africa. Erg Iguidi is one of several Saharan ergs, or sand seas, where individual dunes often surpass 500 meters (nearly a third of a mile) in both width and height. › Larger image Photo: NASA's Goddard Space Flight Center/USGS
2nd Place: Yukon Delta Landsat 7 Acquired 9/22/2002, Countless lakes, sloughs, and ponds are scattered throughout this scene of the Yukon Delta in southwest Alaska. One of the largest river deltas in the world, and protected as part of the Yukon Delta National Wildlife Refuge, the river's sinuous waterways seem like blood vessels branching out to enclose an organ. › Larger image Photo: NASA's Goddard Space Flight Center/USGS