plural of operational service period

(astronomy) The sidereal day of a planet. (I.e., in the definition for "sidereal day", replace "Earth" by the given planet.)

(astronomy) The sidereal year of a planet. (I.e., in the definition for "sidereal year", replace "Earth" by the given planet.)

plural of short-period comet

(astronomy) Any periodic comet with an orbital period of less than 200 years.

plural of short period comet

Alternative form of short-period comet

plural of cooling-off period

plural of psychological refractory period

plural of sidereal orbital period