− Sir Fred Hoyle, British astronomer, 1948
It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small.
− Neil Armstrong
Forty years ago today beings from the planet earth first set foot upon the moon. They came in peace for all mankind.
The image above, captured by astronaut Neil Armstrong, is the first photograph ever taken on the surface of the moon.
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The Apollo missions changed forever the way we view our planet, our universe, and ourselves.
Until Apollo the idea of a spherical earth meant, for most people, that the earth had no edges. A journey on its surface could go on forever. The traveller would encounter an ever-renewing land-and-seascape with no boundaries, edges or drops. In the popular imagination, a round earth meant an endless earth.
All that changed with the Apollo missions. For the first time human beings could look back and see their home world complete. In an instant everything changed. Our home planet now appeared finite, and fragile, and beautiful.
The bonanza of information yielded by the common missions continues to generate new discoveries. At the time the Apollo missions were planned, two theories prevailed about the moon's origin. One, called the 'twin' theory, said that the earth and moon formed at the same time. The other, called the 'adoption' theory, suggested that the moon was a wandering body that had been captured by earth's gravity. Geologists were eager to learn more about the moon's composition so a winner between the two theories could be declared.
The materials returned from the moon contained surprises. The moon, it turned out, is rich in material found in earth's crust, like basalt, but poor in heavy metals, like iron, which are abundant in earth's core and in asteroids. These discoveries threw cold water on both scenarios. If the twin theory were true, both the earth and the moon would be made of similar material in similar proportions. If the adoption theory were true, the moon would have more iron than it does.
Neither theory worked. The surprising likelihood: the moon is actually earth's child, born of an ancient collision between an infant earth and an object the size of Mars.
Today, in preparation for the return of our species to the moon, the Lunar Reconnaissance Orbiter is now mapping the lunar surface. The Orbiter has already managed to glimpse five of the six Apollo landing sites. These historic photos are our first look at the moon bases since we left them. Higher resolution images are soon to come.
The goal of the Orbiter, though, is not to document the past but to help us plan the future. The detailed images of the lunar surface its cameras provide will help scientists to choose sites for future exploration. Project Constellation is America's plan for returning to the moon and journeying beyond to Mars.
A toast to Neil Armstrong, Michael Collins, Buzz Aldrin, and the entire team on this anniversary. Here's to first steps, and to new worlds.