Chapter S1 Flashcards
Why is the Moon’s cycle of phases (the synodic month) longer than the Moon’s orbital period(the sidereal month)
The Moon has to complete more than one full orbit around Earth to complete the cycle of lunar phases
Our current Gregorian calendar usually has a leap year every 4 years, but there are exceptions in some century years (e.g., 2100 will not be a leap year). Which of the following best explains why the calendar needs these exceptions
The length of the tropical year (from one March equinox to the next) is not exactly 365-1/4days.
What is the basic purpose of having leap years
to keep the equinoxes and solstices occurring around the same calendar dates each year
Which of the following best describes the meaning of declination and right ascension
They are coordinates on the celestial sphere, with declination telling us the angular distance of an object from the celestial equator and right ascension telling us how far around the celestial sphere an object is located from the March equinox
All the following statements are true. Which one explains why mean solar time differs from apparent solar time
The length of a solar day is not always exactly 24 hours.
