The largest full moon of 2012 happens this Saturday, but it’s OK if you don’t really notice. The moon doesn’t really get bigger, it just gets closer to Earth (but you knew that).
At 8:40 p.m. Pacific Time on Saturday, according to the Griffith Observatory Sky Report, the moon will be at its closest point in its orbit to the Earth this year. (Accounting for the time zone difference, European moon-watchers will see it Sunday.) To be precise, Earth and moon will be just 221,801 miles apart -- more than 17,000 miles closer than average.
NASA’s Science News calculates the moon’s appearance Saturday will be “as much as 14% bigger and 30% brighter than other full moons of 2012.”
Some call what’s known as a perigee full moon a “supermoon,” which may or may not be accurate. EarthSky gives a lengthy explanation of the term and concludes with this: “Bottom line: The full moon of May 5 (or 6), 2012, is the closest and largest full moon of this year. Some will call it a supermoon.”
But that doesn’t mean you’ll be able to notice the difference. “There are no rulers floating in the sky to measure lunar diameters,” the NASA story says. “Hanging high overhead with no reference points to provide a sense of scale, one full moon can seem much like any other.”
And one downside to the big moon bonanza: The super/biggest moon of the year will likely obscure the Eta Aquarid meteor shower set to peak this weekend.