korihor mentions planetary orbits...was it known back then that planets orbit? is it an anachranism?

Hi jujubee. I'm an astronomer. This was known in Ancient Greece 2,500 years ago. Back then, people thought that the Earth was the centre of the Universe and the planets orbited in circles attached to other circles like a Spirograph. This was the model of the Solar System developed by Ptolemy. Although Aristarchos of Samos supported a heliocentric solar system this was not generally accepted until after Copernicus and Kepler. It was Kepler who finally explained the orbits of the planets with elliptical instead of circular motion.



Edited 1 time(s). Last edit at 01/19/2014 07:24PM by anybody.

so it sounds like it would be fully known in bom times?

it says "planets moving in regular form"

Even so, it was definitely known in Joseph Smith's times. Which is the real question.

I always hated that Korihor scene. Because Mormons like to use it to say how "foolish" Korihor was and had to be corrected.

By the time Joe Smith existed, the orbits of the planets were known. Copernicus had defined them 300 years earlier. Distant galaxies and nebulae had been seen through telescopes. The Book of Abraham displays a lack of understanding the differences between stars and planets. Somehow Joe, though inspired by God, missed some basic facts.

"De revolutionibus orbium coelestium" ("On the Revolutions of the Celestial Spheres") was published in 1543 just before Copernicus died. Kepler published "Astronomia Nova" ("A New Astronomy") in 1609. Sir Issac Newton's "Principia Mathematica" came out in 1667. Knowledge of planetary motion was well known by Joseph Smith's time in the nineteenth century.