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Blue Flash
| Title |
Blue Flash |
| Explanation |
Difficult to observe, the momentary green flash [ http://www.exo.net/~pauld/physics/atmospheric_optics/ green_flash.html ] above the rising or setting sun has been documented as [ http://mintaka.sdsu.edu/GF/ ] a phenomenon caused by the atmospheric bending or refraction of sunlight. Like a weak prism, the Earth's atmosphere breaks white sunlight [ http://micro.magnet.fsu.edu/primer/java/scienceopticsu/newton/ index.html ] into colors, bending red colors slightly and green and blue colors through increasingly larger angles [ http://micro.magnet.fsu.edu/primer/java/ scienceopticsu/refraction/index.html ]. When the sky is clear, a green flash [ http://www.physics.sfasu.edu/astro/research/ sandiego.html ] just above the sun's edge can sometimes be seen for a second or so, when the sun is close to a distant horizon. A blue flash is even harder to see though, because the atmosphere [ http://antwrp.gsfc.nasa.gov/apod/ap000115.html ] must be extraordinarily clear to avoid scattering and diminishing the refracted blue sunlight. Still, from a site near Roques de los Muchachos (altitude 2,400 meters) on La Palma in the Canary Islands [ http://antwrp.gsfc.nasa.gov/apod/ap990410.html ], astrophotographer Mario Cogo captured this dramatic telescopic image of a blue flash on color film in October of 2001. The image of the setting Sun with large sunspot groups [ http://antwrp.gsfc.nasa.gov/apod/ap010315.html ] on its surface is heavily distorted by atmospheric layers. A lingering green rim is just visible under the tantalizing blue flash. |
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Solar Eclipse: A Composite V
…
| Title |
Solar Eclipse: A Composite View |
| Explanation |
Yesterday [ http://www.skypub.com/eclipses/s980226c.html ], the Moon's shadow reached out [ http://pao.gsfc.nasa.gov/gsfc/eclipse/eclipse.htm ] and touched the Earth [ http://umbra.nascom.nasa.gov/eclipse/980226/rp.html ], treating a large portion of the Western Hemisphere to an Eclipse of the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap970827.html ]. This composite image [ ftp://pao.gsfc.nasa.gov/newsmedia/eclipse/COMPOSITE.TXT ] combines pictures of the Sun made from both Earth and space. The central direct image of the solar surface was recorded yesterday by the Extreme Ultraviolet Imaging Telescope [ http://umbra.nascom.nasa.gov/eit/ ] on board the space based SOHO observatory. It is surrounded by a telescopic picture of the Sun as seen from the island of Aruba during the total eclipse. The surrounding view of the eclipsed Sun reveals the gleaming solar corona [ http://sohowww.nascom.nasa.gov/descriptions/mission/english/ wind_and_corona.html ], visible to ground based observers [ http://antwrp.gsfc.nasa.gov/apod/ap951024.html ] during totality. Such combined images can help connect explosive events and features on the Sun's surface with the corona and solar wind. |
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Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date |
06.26.1983 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
|
Earth observations - STS-7
| Title |
Earth observations - STS-7 |
| Description |
Earth observations - STS-7. North part of Western Australia province, Dampier Land, Fitzroy and Lennard Rivers and the Buccaneer Archipelago (35792), Lake Titicaca, on the Peru-Bolivia border. The Bolivian capital city La Paz is also visible (35793), Denham Sound and Shark Bay in Western Australia are easily recognizable (35794), The Mona Loa Volcano, on the island of Hawaii can be seen in this view. A close look reveals lava flows from the active volcano (35795), Africa, Namibia, Grandberg and Cape Cross, Atlantic Ocean as photographed from the Challenger (35796), View of Venezuela, Aruba, Curacao, and Peninsula de Paraguana (35797). |
| Date Taken |
1983-06-26 |
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