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Impossible Moon

The moon is full. Its features are recognisable but impossibly squashed. Earth's atmosphere acts as a giant lens causing the sun and moon close to the horizon to appear higher than their actual position. The refraction strengthens closer to the horizon and thus the lower limb is raised more than the upper one making the disk appear flattened. The flattening is usually up to about 20% and the secret of this image is that it is a moonset seen from the International Space Station. The Moon's rays were refracted on entry into Earth's atmosphere and then again as they traveled out to the ISS. The flattening was therefore doubled.