Pasachoff, Jay M. Hopkins Observatory, Williams College, Williamstown, Massachusetts.
- Additional Readings
The Crab, a northern zodiacal constellation, visible in winter evenings (see illustration). It is the source of the terrestrial name Tropic of Cancer, for the parallel of latitude, about 23½° north of the Equator, where the Sun is 90° overhead at noon on the day of the summer solstice in the Northern Hemisphere (about June 21). The summer solstice used to occur when the Sun was in Cancer, but because of the precession of the equinoxes this point has moved to near the modern boundary between Gemini and Taurus (just within Taurus since 1875). See also: Gemini; Precession of equinoxes; Taurus; Tropic of Cancer; Zodiac
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