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Quote:
Originally Posted by peteremsley View Post
Was just outside - it looks like a pretty normal full moon in CO right now.

There was one a couple of years ago that looked amazing as it rose.
The moon orbit is elliptical with perigee being 357,000 and apogee 406,000 kilometers (222,000 and 252,000 mi, respectively). Average distance is 381500 km or 237,000 miles.

381500/357000 -> 6.8% closer. Inverse square law shows that being 6.8% closer, it will appear 14.2% bigger.

I bet no one can tell the difference by eye. There is a moon illusion created when it is near the horizon. It appears bigger, even though it is the same size at moon-rise and at the highest point in the sky. It is usually only observed in late autumn and winter, when the day is short and the moon rise is observed when dark.

https://en.wikipedia.org/wiki/Moon_illusion
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Old 11-14-2016, 08:28 AM
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