Astronomically Accurate

 The Problems:

 A

You probably know that a year is about 365 days long…the time it takes the Earth to orbit the Sun exactly once. Mid-Summer to Mid-Summer, birthday to birthday, etc

You probably know that one in every four years is a 'leap' year and has 366 days.

Except those century years (1300, 1700 etc) whose first two digits (13, 17 etc) are not divisible by 4… 

So - exactly how long does the earth take to go round the sun (a solar year)?

 B

You’ve doubtless noticed that there’s a ‘full’ moon every month, but you might not know that once every 29.5 months, there are two full moons in a calendar month, because one comes right at the start, while the second just squeezes in at the end…

So - exactly how long does it take the moon to orbit the earth (a lunar month)?

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Last modified: June 18, 2007