nocturnal city and other monsters

[ajawa_took]

   Wondering the city late last night with an Alex from 'tech

Comments

[telso]

does the moon go around the earth in the same direction as the earth rotates, or opposite?Same direction. Viewed from above the North Pole, the Earth revolves counterclockwise around the Sun. Since the Sun moves from East to West in the sky, from that vantage point (above North Pole) the Earth must rotate around its axis counterclockwise. Also, since the sidereal month (time for one full revolution of the Moon around the Earth) is shorter than the synodic month (time it takes for the Moon to reappear in the same place in the sky with respect to the Sun), the Moon must be revolving around the Earth in the same direction as the rotation of the Earth around its axis. (The synodic month is longer because after the Moon has made a full revolution around the Earth, the Earth has made a partial revolution around the Sun, and so the Moon has to travel farther to reach the same position in the sky with respect to the Sun

[fclbrokle]

Actually, the directions of rotation/revolution provides strong evidence for how the solar system formed. The theory is that the planets condensed from a rotating cloud of gas and particles; thus, the rotational momentum of this rotating cloud was imparted to all the objects in the solar system. As a consequence, most everything revolves in the same direction *and* rotates in that same direction as well. Only a few objects violate this; the theory is that some large objects collided with them in the past changing their rotation.

You have tapped into my repressed astronomy geek side. :)

[anonymous]

it's easier to find an answer from the model where the Sun revolves around the Earth.

Every night the Moon is at the same place approx. 1 hour later. Which means that it revolves around the Earth slower than the Sun.

Now, if we from this point assume that the Sun does not revolve, than the Moon revolves in opposite direction. And the Earth, of course, too.

Aren't these animals the famous SF ground squirrels?

[rezoner]

Sorry, I forgot to log in, as usual.

[easwaran]

Whoa, they're famous?!

I guess they've been displaced from campus by eastern tree squirrels that like to follow students.