| Moon--- Western Hemisphere |
Original Caption Released with Image:
This image of the western hemisphere of the Moon was taken through a green
filter by the Galileo spacecraft at 9:35 a.m. PST Dec. 9 at a range of about
350,000 miles. In the center is the Orientale Basin, 600 miles in diameter,
formed about 3.8 billion years ago by the impact of an asteroid-size body.
Orientale's dark center is a small mare. To the right is the lunar near side
with the great, dark Oceanus Procellarum above and the small, circular, dark
Mare Humorum below. Maria are broad plains formed mostly over 3 billion years
ago as vast basaltic lava flows.
To the left is the lunar far side with fewer maria but, at lower left, the
South-Pole-Aitken basin, about 1200 miles in diameter, which resembles
Orientale but is much older and more weathered and battered by cratering. The
intervening cratered highlands of both sides, as well as the maria, are dotted
with bright, young craters. This image was 'reprojected' so as to center the
Orientale Basin, and was filtered to enhance the visibility of small features.
The digital image processing was done by DLR, the German Aerospace Research
Establishment near Munich, an international collaborator in the Galileo
mission.