Suppose you lived on the Moon near the center of the side that always faces Earth.?

Question

Which of the following would you NOT see?

1. Stars crossing your meridian every 27.32 Earth days.
2. Stars rising and setting.
3. The Earth passing through a full cycle of phases.
4. The Earth rising and setting.
5. The Sun crossing your meridian every 29.53 Earth days.

Answer 1

Number 4

In the location you describe (close to the Lunar equator on the near side) you would have a constant view of the Earth. You would watch it change through a full cycle of phases once for every rotation you made around it (29.53 days if your calculations for #5 are correct). You would see stars rise and set as you passed through your orbit, as the Moon keeps one side constantly glued to the Earth and thus a Lunar "day" is the same length as a Lunar "year".

But you would never see the Earth rise or set. It would always be a "Full Earth".

So it's Number 4.

Answer 2

If you just stop and think about it for one moment, it will be obvious. Since the moon shows the same face to the Earth all the time, if you were on that face then the Earth wouldn't move in the moon's sky, would it? So if the Earth doesn't move in the moon's sky (it stays in the same place all the time), which of the above makes sense?

Answer 3

#4. The Earth would be straight overhead, at your zenith, all day and all night. What a cool view that would be! You would be able to watch it as it spins on its axis.

Answer 4

4 of course.

Doug

Answer 5

stars rising and setting.