10 ways the supermoon is moonshine

Tonight, the full moon is supposed to be so freaking HUGE it's a "supermoon."

Here are 10 reasons not to get caught up in the hype.

(1) The term was thought of by an astrologer.

(2) The phenomenon escaped being called "spectacular" for thousands of years, suggesting it really isn't that noticeable.

(3) Every full moon is awesome, and looks especially large when it rises, because of an optical illusion. (This evening, moonrise happens a little before sunset, with max fullness at 9:38 p.m. on the East Coast.)

(4) MEDIA PHOTOGRAPHS OF THE "SUPERMOON" INVOLVE THESE PROCESSES KNOWN AS "ZOOMING IN" AND "ENLARGEMENT." These tricks can be done with any full moon, any time of the year. (See what an unaltered iPhone photo looks like at the top of this story.)

(5) How rare are "supermoons" when 2013 had three, according to the U.S. Naval Observatory; tonight's is the third in a row for 2014, according to NASA; and some astronomers calculate that strictly speaking there were FIVE in 2013 and FIVE this year, including the next one, in October? (Thank the astrologer's 10-percent fudge factor -- the moon doesn't have to be at the exact closest part of its orbit.)

(6) The "supermoon" is NOT 12 to 14 percent wider than an average moon. It's up to 7 percent wider than an average moon (like a regular moon, plus sales tax), or 12 to 14 percent wider than the smallest moons. Media reports, including one Sunday in the New York Times, keep repeating this error.

(7) Just because Superman, the Super Bowl, Superballs, supermodels and supermarkets are on a superlative level compared to other men, bowls, balls, models and markets doesn't mean "supermoons" are mind-boggling. too.

"Not super at, all in my opinion," said Derrick Pitts, astronomer for the Franklin Institute. "But the use of a superlative term shoves people into believing the hype."

"If you have a 16-inch pizza, would you call that a super pizza compared to a 15-inch pizza?" asks "supermoon"-scoffer Neil deGrasse Tyson, astronomer and Cosmos host. (See video.)

(8) Size isn't the only factor in brightness. The weather's obvious, for one thing, but roles are also played by the distance from the sun (greatest during North American winter, not now), and how directly opposite the moon is from the sun, suggesting some winter "micromoons" might rival hazy summer "supermoons" for brightness.

(9) How possible is it to accurately recall past full moons to compare to the latest one? "Prove to me you can see the difference - I dare ya!" emailed Pitts. "... A casual observer will not have anything against which to compare the different sizes."

(10) If "super" is OK to use for anything blown out of proportion, then media coverage of the "supermoon" should be called "super-reporting" with "superphotography."

Contact staff writer Peter Mucha at 215-854-4342 or pmucha@phillynews.com. Follow @petemucha on Twitter.