Generous sponsorship of Windows to the Universe is provided by the Hewlett Foundation, the American Geological Institute, the National Science Foundation, NASA, NCAR, and the CISM and CMMAP projects. NASA CMMAP CISM NCAR Hewlett AGI NSF
An artist's rendering of the moment of impact of a massive <a href="/our_solar_system/meteors/meteors.html">meteorite</a> at the end of the Cretaceous (at the end of the <a href="/earth/geology/hist_mesozoic.html">Mesozoic Era</a>). Many scientists have concluded for decades that a meteorite four to six kilometers in diameter impacted the Earth at this time, resulting in a <a href="/earth/past/KTextinction.html">mass extinction of dinosaurs</a> and many other life forms.  Recent research suggests that perhaps <a href="/headline_universe/olpa/chicxulub.html">massive volcanic eruptions</a> may be been responsible for the extinction.<p><small><em>Courtesy of Don Davis, NASA</em></small></p>There are over 900 <a href="/the_universe/uts/megalith.html">rings of stone</a> located in the British Isles. The most famous of these stone rings is of course, <a href="/the_universe/uts/stonehenge.html">Stonehenge</a>. The stones of Stonehenge were put in place between 3,000 B.C and 2,000 B.C. by neolithic people.Some speculate that the site was built as a temple of worship of the ancient Earth deities. Some say it was used as an <a href="/the_universe/uts/stonehenge_astro.html">astronomical observatory</a> of sorts. Still others say it was a burial ground.<p><small><em> Image courtesy of Corel Photography.</em></small></p>Stars don't last forever. Occasionally, a star bigger than our Sun will end its life in a huge explosion, called a <a href="/the_universe/supernova.html">supernova</a>. The center of the star collapses in less than a second, blowing away the outer layers of the star. There are many beautiful images of supernova remnants, the expanding shell of gas made up of the outer layers of the original star. This image is the Vela Supernova Remnant.<p><small><em>Image courtesy of the Anglo-Australian Observatory/Royal Observatory Edinburgh</em></small></p>Anti-crepuscular rays are beams of sunlight that appear to converge on a point opposite the sun. They are similar to crepuscular rays, but are seen opposite the sun in the sky. Anti-crepuscular rays are most frequently visible near sunrise or sunset. This photo of anti-crepuscular rays was taken at sunset in Boulder, Colorado. Crepuscular rays are usually much brighter than anti-crepuscular rays.<p><small><em> Image Courtesy of Carlye Calvin</em></small></p>A group of Emperor penguins wait their turn to dive into the ocean near <a href="/people/postcards/jean_pennycook_11_29_0.html">Ross Island, Antarctica</a> on November 3, 2004. Emperor penguins routinely dive to 500 meters in search of food.  Scientists are interested in understanding how they can endure the stress of these dives in such an <a href="/earth/extreme_environments.html">extreme environment</a>.<p><small><em>Image courtesy of Emily Stone, National Science Foundation</em></small></p>This dramatic view of Jupiter's <a href="/jupiter/atmosphere/J_clouds_GRS.html">Great Red Spot</a> and its surroundings was obtained by <a href="/space_missions/voyager.html">Voyager 1</a> on Feb. 25, 1979, when the spacecraft was 5.7 million miles (9.2 million kilometers) from Jupiter. Cloud details as small as 100 miles (160 kilometers) across can be seen here. The colorful, wavy cloud pattern to the left of the Red Spot is a region of extraordinarily complex end variable wave motion.<p><small><em>Image courtesy of NASA</em></small></p>

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Welcome to Windows to the Universe - your portal to discovery! Explore the wealth of information available here to learn about the Earth and Space sciences and related topics in the humanities including mythology, art, poetry, and more.

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Podcasts from the National Science Foundation

Geologists at Harvard University found evidence that sea ice extended to the equator up to 716.5 million years ago. Listen to this and other podcasts ...Read more
Brought to you by NSF

Clouds in Art

Landscape painters have been representing clouds in their art for centuries. Different artists with different styles have painted clouds differently. Check out the Clouds in Art Interactive ...Read more
Brought to you by CMMAP

Physics of Space Weather

The science of physics plays a key role in many space weather phenomena. Charged particles, magnetic fields, forces and motion, and the electromagnetic spectrum are all part of space weather ...Read more
Brought to you by CISM

Atmospheric Optics

Atmospheric optics shows us how light behaves as it passes through the atmosphere. From rainbows to the northern lights, these optical features allow us to learn about atmospheric conditions ...Read more

Galaxies

Galaxies are huge collections of stars, gas and dust, and mysterious dark matter. Galaxies are thousands of light years across and contain billions of stars. We are in the Milky Way galaxy ...Read more

Upcoming Earth & Space Science Historical Events

9/7 Great Chesapeake Bay Hurricane of 1769 Details

9/10 Stephen Jay Gould, an American paleontologist, was born on this date in 1941 Details

9/12 Series of Major Earthquakes hit Sumatra, 2007 Details

9/14 Giovanni Cassini, an Italian-French astronomer, died on this date in 1712 Details

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Did you know?

Did you know that the Earth’s lithosphere is broken into giant plates, which occasionally move and can produce earthquakes?

Buried Treasure!

Exploration of the Poles of the Earth

Polar exploration includes the physical exploration of the Arctic and the Antarctica. The Arctic is the...Read more

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