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Astronomy 2e

Figuring for Yourself

Astronomy 2eFiguring for Yourself

Figuring for Yourself

49.

Suppose Earth took exactly 300.0 days to go around the Sun, and everything else (the day, the month) was the same. What kind of calendar would we have? How would this affect the seasons?

50.

Consider a calendar based entirely on the day and the month (the Moon’s period from full phase to full phase). How many days are there in a month? Can you figure out a scheme analogous to leap year to make this calendar work?

51.

If a star rises at 8:30 p.m. tonight, approximately what time will it rise two months from now?

52.

What is the altitude of the Sun at noon on December 22, as seen from a place on the Tropic of Cancer?

53.

Show that the Gregorian calendar will be in error by 1 day in about 3300 years.

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