Earthrise

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"Earthrise" taken on December 24, 1968

Earthrise is a photograph of the Earth taken by astronaut William Anders in 1968, during the Apollo 8 mission. Nature photographer Galen Rowell declared it "the most influential environmental photograph ever taken."[1] This had been preceded by the crude 1966 black-and-white raster earthrise image taken by the Lunar Orbiter 1 robotic probe.

Details

File:Earthrise conversation.ogg
The conversation between Frank Borman and William Anders, during the taking of the Earthrise photograph

Earthrise is the name given to NASA image AS8-14-2383, taken by astronaut William Anders during the Apollo 8 mission, the first manned voyage to orbit the Moon.[1][2]

Initially, before Anders found a suitable 70 mm color film, mission commander Frank Borman took a black-and-white photograph[3] of the scene, with the Earth's terminator touching the horizon. The land mass position and cloud patterns in this image are the same as those of the color photograph entitled Earthrise.[4]

The photograph was taken from lunar orbit on December 24, 1968, with a highly modified Hasselblad 500 EL with an electric drive. The camera had a simple sighting ring rather than the standard reflex viewfinder and was loaded with a 70 mm film magazine containing custom Ektachrome film developed by Kodak. An audio recording of the event is available[5] with transcription[6] which allows the event to be followed closely – excerpt:[7]

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Anders: Oh my God! Look at that picture over there! There's the Earth coming up. Wow, is that pretty.
Borman: Hey, don't take that, it's not scheduled. (joking)
Anders: (laughs) You got a color film, Jim?
            Hand me that roll of color quick, would you...
Lovell: Oh man, that's great!

Earthrise video captured by Apollo 10 crew in 1969

There were many images taken at that point. The mission audio tape establishes several photographs were taken, on Borman's orders, with the enthusiastic concurrence of Lovell and Anders. Anders took the first color shot, then Lovell who notes the setting (1/250th of a second at f/11), followed by Anders with another two at varying exposures.

A nearly full-page black and white reproduction of Borman's image may be viewed on page 164 of his 1988 autobiography, captioned, "One of the most famous pictures in photographic history — taken after I grabbed the camera away from Bill Anders". Borman was the mission commander and notes[8] (pg. 212) that this is the image "the Postal Service used on a stamp, and few photographs have been more frequently reproduced" [but see above]. The photograph reproduced in the Frank Borman autobiography is not the same image as the Anders photograph; aside from the orientation, the cloud patterns differ.

The stamp issue reproduces the cloud, color, and crater patterns of the Anders picture. Anders is described (pg. 193) by Borman as holding "a masters degree in nuclear engineering"; Anders was thus tasked as "the scientific crew member ... also performing the photography duties that would be so important to the Apollo crew who actually landed on the Moon".

Geometry

The as-published photograph shows Earth:

  • Polar orientation: south to left, north to right (Antarctica at 10 o'clock)
  • Equator: center, running westward toward top right-hand corner
  • Nightfall terminator crossing the African continent (lightish region to left is Namib Desert, Namibia; to right is Western Sahara/West Africa)
  • Rotated clockwise approximately 135° from our typical North/South-Pole-oriented perspective

Legacy

In Life 's 100 Photographs that Changed the World, wilderness photographer Galen Rowell called Earthrise "the most influential environmental photograph ever taken."[9] Another author called its appearance the beginning of the environmental movement.[10]

Stamp

In 1969, the U.S. Postal Service issued a stamp (Scott# 1371) commemorating the Apollo 8 flight around the Moon. The stamp featured a detail (in color) of the Earthrise photograph, and the words, "In the beginning God...", recalling the Apollo 8 Genesis reading.

2008 video

On April 6, 2008 (Japan Standard Time), the first 1080p high-definition Earthrise video was captured, both a full Earthrise and Earthset video, by the JAXA lunar orbiter mission, SELENE (better known in Japan by its nickname Kaguya). After successfully orbiting the Moon for 1 year and 8 months, it was crashed intentionally onto the lunar surface at 18:25 UTC on June 10, 2009.[11]

2013 simulation video

File:Earthrise.ogv
A simulation of what the Apollo 8 crew saw as the Earth rose above the lunar horizon during their fourth orbit around the Moon that pauses to overlay two photographs taken by the crew and includes a clock overlay

In 2013, in commemoration of the 45th anniversary of the Apollo 8 mission, NASA issued a video about the taking of the photograph.[12] This computer-generated visualization used data from the Lunar Reconnaissance Orbiter spacecraft, which had provided detailed images of the lunar surface that could be matched with those taken every 20 seconds by an automatic camera on Apollo 8. The resulting video, re-creating what the astronauts would have seen, was synchronized with the recording of the crew's conversation as they became the first humans to witness an Earthrise. The video included explanatory narration written and read by Andrew Chaikin.[13]

Potential earthrises as seen from the Moon's surface

File:New High-Resolution Earthrise Image.jpg
The Earth straddling the limb of the Moon, as seen from above Compton crater. Taken by the Lunar Reconnaissance Orbiter.

An earthrise that might be witnessed from the surface of the Moon would be quite unlike moonrises on Earth. Because the Moon is tidally locked with the Earth, one side of the Moon always faces toward Earth. Interpretation of this fact would lead one to believe that the Earth's position is fixed on the lunar sky and no earthrises can occur, however, the Moon librates slightly, which causes the Earth to draw a Lissajous figure on the sky. This figure fits inside a rectangle 15°48' wide and 13°20' high (in angular dimensions), while the angular diameter of the Earth as seen from Moon is only about 2°. This means that earthrises are visible near the edge of the Earth-observable surface of the Moon (about 20% of the surface). Since a full libration cycle takes about 27 days, earthrises are very slow, and it takes about 48 hours for Earth to clear its diameter.[14] During the course of the month-long lunar orbit, an observer would additionally witness a succession of "Earth phases", much like the lunar phases seen from Earth. That is what accounts for the half-illuminated globe seen in the photograph.

See also

References

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  11. KAGUYA (SELENE)Image Taking of "Full Earth-Rise" by HDTV April 11, 2008 (JST), Japan Aerospace Exploration Agency (JAXA),Japan Broadcasting Corporation (NHK)
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External links