| 释义 |
‖ proemptosis Chronol.|prəʊɛm(p)ˈtəʊsɪs|
[mod.L., f. pro-2 + ἔµπτωσις a falling in or on: cf. προεµπίπτειν to fall on before: cf. metemptosis.]
An anticipation or occurrence of a natural event earlier than the time given by a rule; esp. the occurrence of the new moon earlier than the Metonic cycle or 19 years' period would make it; also, loosely applied to the lunar equation or correction necessary to bring the calendar into agreement with the actual new moon.
The name proemptosis had reference to the Julian Calendar, according to which the actual new moon occurred ·06 day earlier than the 19-year cycle provided; in 19 tropical years and their approximation in the Gregorian Calendar the new moon occurs ·09 day later than provided for by the cycle.
1727–41Chambers Cycl., Proemptosis, in astronomy, that which makes the new moons appear a day later, by means of the lunar equation, than they would do without that equation. |