Earthrise Like You’ve Never Seen It Before
Nearly 47 years ago, the crew of Apollo 8 took an image of planet Earth from the Moon that has been called “the most influential environmental photograph ever taken.” Called “Earthrise,” the picture represented the first time human eyes saw their homeworld come into view around another planetary body.
Now, the Lunar Reconnaissance Orbiter (LRO) has captured stunning new high-definition views of Earth and the Moon from the spacecraft’s vantage point in lunar orbit.
This is a composite view, with Earth appearing to rise over the horizon of the lunar farside. The image is composed from a series of pictures taken on Oct. 12, 2015 when LRO was about 83 miles (134 kilometers) above the moon’s farside Compton crater.
Taking this image was actually a complicated task for the LRO team. Mark Robinson, the principal investigator for LROC camera explained:
First the spacecraft must be rolled to the side (in this case 67°), then the spacecraft slews with the direction of travel to maximize the width of the lunar horizon in the NAC (Narrow Angle Camera) image. All this takes place while LRO is traveling over 1,600 meters per second (faster than 3,580 mph) relative to the lunar surface below the spacecraft! As a result of these three motions and the fact that the Narrow Angle Camera is a line scanner the raw image geometry is distorted. Also, because the Moon and Earth are so far apart, the geometric correction is different for each body. Reconstruction of the Earth-Moon image is not a simple matter – and that is just to get the black and white image!
Here’s a video created by the LRO Mission Operations Center showing how they planned the maneuver with a specialized spacecraft slew planning software. The vertical red line indicates the NAC line scan:
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