photo credit: Nils van der Burg

Bob Miller's Light Walk

These pinhole images of the sun, made by the small openings between leaves, show a nearly-total solar eclipse (see the Exploratorium site Solar Eclipse). For more about pinhole images, see Bob Miller's Light Walk and Pinhole Investigations (also Exploratorium sites).

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Astro-Venture

Try this NASA site if you'd like to develop a mission to a habitable planet. You can get interactive online training--with lots of graphics--in astronomy, atmospheric science, geology, and biology. Then, using what you've learned, you can design a planet tailor-made for life.

For more on the habitability of planet Earth, see Life on Earth and Elsewhere.

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Contrails

image credit: National Oceanic and Atmospheric Administration/Department of Commerce
hi-res version

The false-color image above shows jet contrails in the skies above the mid-Atlantic coast on 1/26/2001. Check out this photo taken on the ground at about the same time.

When U.S. commercial air traffic was grounded following the 9/11 attacks, atmospheric scientists took advantage of this opportunity to investigate the effect of jet contrails on Earth's climate. The results showed that contrails produced cooler days--more sunlight was reflected from the contrails--and warmer nights--more heat radiated from Earth was trapped (this trapping is the greenhouse effect).

Click for additional contrail images and discussion.

Sport Science

Visit Sport Science to learn about the science of skateboarding, surfing, cycling, and more. You can also find out how hand mechanics are key in rock climbing.