This image from Apollo 17, and others like it, captured whole hemispheres of water, land and weather.
This image from Apollo 17, and others like it, captured whole hemispheres of water, land and weather. This photo was the first view of the south polar ice cap. Almost the entire coastline of Africa is visible, along with the Arabian Peninsula.

WASHINGTON -- NASA is inviting the public to vote online for the most important contribution the space agency has made to exploring Earth and improving the way we live on our home planet. NASA is conducting the survey as part of its celebration of Earth Day, April 22. Voting begins today, and closes on April 21. Poll results will be announced on NASA's Web site on Earth Day.

For more information and o cast your votes, visit:
http://www.nasa.gov/topics/earth/earthday/greatest_hits.html

For more information about Earth Day and NASA, visit:
http://www.nasa.gov/earthday


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