The BBC News website ran the following news article about the 'snow' moon and partial lunar eclipse that occurred on 10th February, 2017 (a snow moon is a full moon that occurs during February):
Spectacular snow moon regales world
February's full moon also coincides with a partial lunar eclipse.
Now, a lunar eclipse can only occur when the Moon is 'full', i.e. on the opposite side of the Earth to the sun. So, in what sense can they be said to coincide? The Cambridge Dictionary gives the following definition for coincide:
coincide verb [ I ]
to happen at or near the same time:
- I timed my holiday to coincide with the children's.
- If the heavy rain had coincided with an extreme high tide, serious flooding would have resulted.
Does it make sense to say:
February's full moon also coincides with a partial lunar eclipse.
The BBC seem to think so. Would it also make sense (or more or less sense) to put it the other way around, and say:
A partial lunar eclipse also coincided with February's full moon.
Does it make any difference, especially when one event cannot occur without the other?
Best Answer
I agree with you that the sentence is a bit awkward (or "redundant", as Papa Poule aptly put it in his comment above); normally we wouldn't say that two things "coincide" unless it's conceivable that they could take place at different times. For example, I think something like this is obviously bad:
Your example, however, does not seem anywhere near as bad as this one. I think the difference has to do with how obvious and fundamental the redundancy is; if he's turning 21 on a given day, then that day is obviously his birthday, by definition. (In anglophone cultures, that is.) By contrast, I think most people would need a second to recall (or realize) that lunar eclipses can only happen during the full moon; that may be a true fact about the world, but it's not such a basic and well-known fact as to make it inconceivable, in people's imaginations, that an eclipse could happen at another time.