24 Apr '11, 10pm

Sunset over Western South America [image] #NASA

Astronauts onboard the International Space Station see, on average, 16 sunrises and sunsets during a 24-hour orbital period. Each changeover between day and night is marked by the terminator, a line on Earth's surface separating the sunlit side from the darkness. While the terminator is often conceptualized as a hard boundary—and is frequently presented as such in graphics and visualizations —in reality the edge of light and dark is diffuse due to the scattering of light by the Earth’s atmosphere. This zone of diffuse lighting is experienced as dusk or twilight on the ground; while the Sun is no longer visible, some illumination is still present due to light scattering over the local horizon. The terminator is visible in this panoramic view across central South America, looking towards the northeast. An astronaut shot the photo at approximately 7:37 p.m. local time. Layers...

Full article: http://earthobservatory.nasa.gov/IOTD/view.php?id=50205&s...

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See a sunset over Western South America as the ...

earthobservatory.nasa.gov 25 Apr '11, 1am

Astronauts onboard the International Space Station see, on average, 16 sunrises and sunsets during a 24-hour orbital perio...

Sunset over Western South America: The changeov...

earthobservatory.nasa.gov 24 Apr '11, 10pm

Astronauts onboard the International Space Station see, on average, 16 sunrises and sunsets during a 24-hour orbital perio...

Sunset from the International Space Station.

earthobservatory.nasa.gov 24 Apr '11, 10pm

Astronauts onboard the International Space Station see, on average, 16 sunrises and sunsets during a 24-hour orbital perio...

Jizzax Province, Uzbekistan [image] #NASA

earthobservatory.nasa.gov 24 Apr '11, 2am

Uzbekistan is a dry, landlocked country, covered mostly by the sands of the Kyzyl Kum (Qizilqum) Desert. A little over 10 ...

Earth's Magnetosphere [image] #NASA

earthobservatory.nasa.gov 22 Apr '11, 10pm

You've seen the pattern in science class when you laid bits of iron around a bar magnet. The invisible force field around ...

Elevation Map of Badain Jaran Desert [image] #NASA

Elevation Map of Badain Jaran Desert [image] #NASA

earthobservatory.nasa.gov 19 Apr '11, 10pm

Spread sand on an even surface so that the layer is perfectly flat. You might think that gravity should keep the layer eve...

America's Farmers Are Second to None - Renewabl...

renewableenergyworld.com 24 Apr '11, 3pm

There are a lot of special interests looking to profit from American families. Not surprisingly, these are the same compan...

The Endangered Macaws of Central America and South America

The Endangered Macaws of Central America and So...

environmentalgraffiti.com 13 Apr '11, 10am

Macaws belong to seventeen species within six branches of the parrot family, Psittacidae . They are known for their brilli...

Jizzax Province, Uzbekistan: Acquired September...

earthobservatory.nasa.gov 23 Apr '11, 10pm

Uzbekistan is a dry, landlocked country, covered mostly by the sands of the Kyzyl Kum (Qizilqum) Desert. A little over 10 ...

Jizzax Province, Uzbekistan: Acquired September...

earthobservatory.nasa.gov 23 Apr '11, 10pm

Uzbekistan is a dry, landlocked country, covered mostly by the sands of the Kyzyl Kum (Qizilqum) Desert. A little over 10 ...

Northwest Greenland Canyons [image] #NASA

earthobservatory.nasa.gov 30 Apr '11, 10pm

Launched in March 2009, NASA’s IceBridge mission is the world’s largest airborne survey of polar ice. The mission is aimed...

Islands off the Croatian Coast [image] #NASA

earthobservatory.nasa.gov 16 Apr '11, 10pm

Along the coast of Croatia lies a multitude of islands of varying shapes and sizes. Archaeological finds indicate that som...

Almost 300 Dead After Tornadoes in South: How You Can Help: via @addthis

Almost 300 Dead After Tornadoes in South: How Y...

care2.com 29 Apr '11, 5am

In any building, underground is safest, if possible, but stay as close to walls and if possible in corners as you can. Rem...