-
Ptolemy believed that the earth was the center of the universe.
-
Copernicus believed that the sun was at the center of the universe, motionless, with Earth and the other planets orbiting around the sun.
-
Galileo was trying to prove that the sun was in a different position every 6 months
-
ALL objects attract each other with a force of gravitational attraction.
-
Herschel built large telescope's in order to discover that we are located in a disk of stars
-
Shapley's calculation puts the sun at 50,000 light years away from the sun in the direction of Sagittarius.
-
The distant galaxies we see in all directions are moving away from the Earth, as evidenced by their red shifts. Hubble's law describes this expansion.
-
Einstein's theory holds that space itself is curved near a massive object and that the curvature causes the acceleration that previously had been attributed to the force of gravity.