2007-11-22 13:33:40 · 4 answers · asked by lirael1019 1 in Science & Mathematics ➔ Astronomy & Space
Kepler had a vast database of observations of planetary positions. After years of work, he realized that the only way the observations made sense was if the orbits were eliptical. It was Newton who discovered the reason why.
2007-11-22 13:39:36 · answer #1 · answered by Anonymous · 6⤊ 0⤋
I think he concluded this when trying to explain the planetary motions. Circular motions could not explain the positions of the planets at any particular moment. Elliptical motion pinpointed the positions much better (aside from perturbations caused by unknown planets). A two body system requires having a centre of gravity between the two bodies, so it cannot be circular. In the case of the planets, the centre of gravity lies well within the Sun, so the orbits are only slightly off centre, but elliptical, none the less.
2007-11-22 13:45:48 · answer #2 · answered by Labsci 7 · 1⤊ 0⤋
Contrary to what # 1 said, it's the tilt of the earths axis, lowering the angle of the sun, not the eccentricity of the the earths orbit that causes the seasons. The distance from the earth to the sun is only enough to affect the temp by about 5 degrees. Not to mention the fact that when it's Summer in the northern hemisphere it's winter in the southern hemisphere.
2007-11-22 13:52:23 · answer #3 · answered by Anonymous · 1⤊ 1⤋
simple.....seasons vary.....
2007-11-22 13:37:56 · answer #4 · answered by Anonymous · 0⤊ 6⤋