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8 Cards in this Set

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  • Back
Sidereal period
The period of revolution of one body about another with respect to the stars.
Synodic period
how long it takes a planet to move on the celestial sphere and return to the same arrangement relative to the sun
Sidereal day
the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day
Solar day
The period of time between the instant when the Sun is directly overhead (ie at noon) to the next time it is directly overhead
Sidereal month
Time required for the Moon to complete one trip around the celestial sphere (27.32 days)
Synodic month
Time required for the Moon to complete a full cycle of phases. (about 29.5 days)
Sidereal year
The time required for the constellations to complete once cycle around the sky and return to their starting points, as seen from a given point on Earth. (365.2564 mean solar days)
Tropical year
The time interval between one vernal equinox and the next. (365.2422 mean solar days)