Buy this Earth & Moon from Mercury photo. High quality Mercury MESSENGER space picture, poster, slide, or Duratrans backlit transparency. NASA Photograph EW101655888. Wide variety of sizes.
The pair of bright star-like features are not stars at all, but the Earth and Moon! MESSENGER was at a distance of 98 million kilometers (61 million miles) from Earth when this picture was taken.
MESSENGER took this image as part of a campaign to search for natural satellites of Mercury. Mercury has no moons that we know of. If any exist, they must be small, or we would have seen them by now. The strategy for the satellite search involves taking multiple images of locations at predetermined distances from Mercury.
The Earth and Moon appear very large in this picture because they are overexposed. When looking for potentially dim satellites, long exposures are required to capture as much light as possible. Consequently, bright objects in the field of view become saturated and appear artificially large. In fact, the Earth and Moon are each less than a pixel in size, and no details on either can be seen. The “tails” pointing downward from the Earth and Moon are artifacts caused by the image saturation.
This image was taken on the same day that images with Earth in the scene were acquired by the Cassini spacecraft, as part of a mosaic of the backlit Saturn system.
Date Acquired: July 19, 2013
Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington