# The Difference between Revolving and Rotating

Given:

The moon is a satellite of the earth, revolving around the earth once every twenty-nine and a half days. The moon itself rotates very slowly but it does so very slowly.

Question:

How does the moon rotate around the earth?

1. The moon rotates around the earth once every twenty-nine and a half days.

2. The moon rotates around the earth, revolving very slowly.

Which answer is suitable, manner or interval?

• Curious, where are you getting this given statement, question, and possible answers from? Commented Jun 28, 2017 at 14:01
• They are making a useful distinction, but unfortunately English speakers don't always observe the distinction. Dictionary. com gives meaning 1 for rotate: "to cause to turn around an axis or center point; revolve"; but while meaning 1 for revolve is "to move in a circular or curving course or orbit", meaning 2 is "to move in a circular or curving course or orbit". So the distinction is not as clear-cut as this implies. Commented Jul 27, 2020 at 15:35
• @ColinFine In the physical world the distinction is not clear cut. In the world of astronomy, ergo this question, the distinction is quite clear. Heavenly orbs revolve around other orbs and rotate, if at all, on their axes. Commented Jul 27, 2020 at 15:46

Neither answer is correct. The Moon does not rotate around the Earth. It revolves around the Earth. This information is provided in your Given clause.

The Given states that the Moon revolves around the Earth and rotates [on its axis] very slowly. It then asks how the Moon rotates around the Earth. It doesn't rotate around the Earth. It rotates around its axis, very slowly.

Whoever wrote the question may need to revisit the definitions.

If answer #2 was to be correct, it would read, "The moon revolves around the Earth, rotating very slowly."

To Revolve is to rotate around something else.

Ergo, something which rotates will revolve about its central axis. It is revolving, but it is revolving about the central axis. That same object can rotate about its central axis and it means the same thing.

All things can rotate, but something else must be present if it wishes to revolve.

Therefore, `2. The moon rotates around the earth, revolving very slowly.`, is incorrect. I believe if we are trying to imply `...revolving (around the earth) very slowly` then it is correct. However, in this instance, I think it is meant to attempt to use `revolving` in place of `rotating`, which is just incorrect.

"How" has 7 different definitions as an adverb (dictionary.com). In this situation, only two are really applicable.

• In what way or manner?
• For what reasons?

The second definition is not an option. Thus, the answer that addresses the manner would be the better answer. I would argue that both actually address the manner - but regardless, #2 is more correct because it is more direct and conventional in answering the question.

The moon is a satellite of the earth, revolving around the earth once every twenty-nine and a half days. The moon itself rotates very slowly but it does so very slowly.

Given the text above, you answer 1) would be correct.

Revolving around the earth is similar to "rotate around the earth". So you can just pick what the text used to describe the revolving.

The second answer talks about the self-revolving of moon, which is not directly relevant to the question.

• Thank you. So, without "around the earth", just "revolving" usually means "self-revolving", right? Commented Apr 6, 2020 at 0:30
• Well. That's a present participle question. With or without the "around the earth", the subject of the present participle "revolving" here is the same as that of the main clause, which is the moon. Commented Apr 9, 2020 at 1:29
• The point of interest in the original question is revolution vs rotation. The Moon rotates on its axis and revolves around the Earth. The question, "How does the Moon rotate," asks for an answer concerning rotation. Neither answer is correct. Commented Jul 27, 2020 at 14:33
• The question in the content is the key, not the title "revolution vs rotation". The guy just wanted to know the answer I guess. Similar questions are also seen in exams of EnglishAsSecondLanguage environments. I would assume native English speakers don't see those often. But I get those a lot in my learning. Commented Jun 14, 2022 at 2:02