Photo #: ISS008-E-8951 Date: Dec. 2003 Geographic Region: ASTRONOMICAL OBJECTS Feature: PAN-CRESCENT MOON, EARTH LIMB |
Thinning Upper Atmosphere: From a vantage point about 360 km (225 miles) over the Earth, Space Station crewmembers photographed the crescent moon through the upper layers of Earth's atmosphere. At the bottom of the image, a closed deck of clouds is probably at about 6 km (3 miles). The shades of blue grading to black are caused by the scatter of light as it strikes gas molecules of the very low density upper atmosphere. Models predict that emissions of carbon dioxide are causing the upper atmosphere to cool and contract, and therefore reduce the density of gases in the layer spanning from 90 to 649 km (60 to 400 miles) above the surface--known as the thermosphere. According to a study by the Naval Research Laboratory (//www.agu.org/sci_soc/prrl/prrl0406.html), the density of the thermosphere has decreased about 10 percent over the last 35 years. These findings are important both for space science and for Earth science. Spacecraft in orbit, such as the International Space Station, experience less drag and need fewer boosts to maintain their orbit. At the same time, space debris also remains in orbit longer, which increases hazards to spacecraft. Most importantly, the study validates models of the "greenhouse effect" of increased carbon dioxide release on the dynamics of the atmosphere. |
Images: | All Available Images Low-Resolution 61k |
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Mission: | ISS008 |
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Roll - Frame: | E - 8951 |
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Geographical Name: | ASTRONOMICAL OBJECTS |
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Features: | PAN-CRESCENT MOON, EARTH LIMB |
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Center Lat x Lon: | N x E |
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Film Exposure: | N=Normal exposure, U=Under exposed, O=Over exposed, F=out of Focus |
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Percentage of Cloud Cover-CLDP: | 25 |
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Camera:: | N1 |
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Camera Tilt: | HO | LO=Low Oblique, HO=High Oblique, NV=Near Vertical |
Camera Focal Length: | 800 |
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Nadir to Photo Center Direction: | S | The direction from the nadir to the center point, N=North, S=South, E=East, W=West |
Stereo?: | Y=Yes there is an adjacent picture of the same area, N=No there isn't |
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Orbit Number: | 984 |
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Date: | 20031218 | YYYYMMDD |
Time: | 154429 | GMT HHMMSS |
Nadir Lat: | 38.9N |
Latitude of suborbital point of spacecraft |
Nadir Lon: | 13.3W |
Longitude of suborbital point of spacecraft |
Sun Azimuth: | 221 | Clockwise angle in degrees from north to the sun measured at the nadir point |
Space Craft Altitude: | 199 | nautical miles |
Sun Elevation: | 16 | Angle in degrees between the horizon and the sun, measured at the nadir point |
Land Views: | MOON |
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Water Views: | |
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Atmosphere Views: | |
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Man Made Views: | |
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City Views: | |
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Photo is not associated with any sequences |
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