Celestial Time Keeping Flashcards
Simple principles that allow you to determine your location on Earth
celestial navigation
The ? Was the only guide to ? For most of human history
Sky. Time.
If you learn the constellations, bright stars, and ??of the sky you will feel right at home
Apparent motion
Earth’s rotation period
Sidereal day
4 minutes shorter than a 24 hour solar day. Noon to noon.
Moon’s orbital period of 27 1/3 days
Sidereal month
29 1/2 days required for moons cycle of phases
Synodic month
Sidereal year
Earths orbit. 20 minutes longer than tropical year= one spring equinox to the next.
Planet’s ?? Is its orbital period
Sidereal period
A planet’s ?? Is its time from one opposition or conjunction to the next
Synodic period
Five ways to tell time
A.Apparent solar. Sun’s position in the local sky
B.Mean solar. local but averages suns rate of motion
C. Standard and
D. daylight saving time
E. Universal time mean solAr time in Greenwich.
What is declination
Angle describing a location of north or south on the celestial sphere
Transit
Planet passes across star or sun as seen from earth. Venus
