Chronicled events
- #5798
The Earth is a planet. It spins once a day and circles the Sun once a year, as the other planets do, with the Sun near the center of it all.
#5800The air near the Earth turns with it and carries the clouds along, and whatever rises or falls through the air turns with the Earth too, on top of its own motion. So we see them move every which way, as they would on a motionless Earth.
#5801Ptolemy’s system has to set by hand that Mercury and Venus never stray far from the Sun, and that the outer planets loop backward just when they’re opposite the Sun in the sky. It never explains why. If the Earth and the planets all circle the Sun, both follow.