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Is there such a thing as a “lunar” Arctic Circle? The short answer is “yes”, though it is a much more dynamic one than the more familiar solar equator.1 The lunar inclination is approximately, 5° 8′. So, given the tilt of the Earth’s axis, 23° 26′, this puts the lunar Arctic Circle at 90 – (23° 26′ + 5° 8′) or 61° 28′. Given the right circumstances the Moon would thus be visible due north at that latitude; any further south and it would dip below the horizon.