Measuring the Distances Between Planets
Name: doug a foster
Date: 1993 - 1999
How do scientists measure the size of the other planets and their
distances from the earth?
Kepler, essentially, did it, and it wasn't simple. The idea is
basically that if I know a planet's orbit around the sun, and I know where the
planet appears to be at two different positions of the earth in the earth's
orbit, then I can figure the distance to the planet by triangulation. Once I kn ow the distance, figuring
the size is straight trigonometry based upon the planet's apparent size. It all
checks, because the planet's distance from the sun can be calculated from the
length of its year.
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Update: June 2012