'Super moon' in the sky this weekend
You won't be imagining it: The moon really will appear larger and brighter than usual this weekend.
In fact, this weekend's moon will be the "super moon" of 2013.
That's because two key points in the lunar cycle will coincide early Sunday morning -- the moon will both be a full moon and at its closest point to Earth in the 29.5-day cycle.
In recent years, moon watchers have begun using the term "super moon" to describe that occurrence.
The perigee -- the name for the point in a lunar cycle when the moon is nearest to Earth -- will occur at 7:11 a.m. Sunday, when the body will be 356,911 kilometers, or 221,774 miles, from Earth.
Just 22 minutes later, at 7:33 a.m., Philadelphia will see a full moon, according to the U.S. Naval Observatory.
The phenomenon happens about every 413 days.
The next time a full moon and perigee coincide so closely isn't until August 2014. A full moon and perigee occurred within an hour of each other in March 2011 and May 2012, both resulting in "super moons."
Perigee moons are about 14 percent bigger and 30 percent brighter than moons on the far end of the body's orbit from Earth, according to NASA. And the full moon will enhance our perception of its size.
So, when is the best time to see the "super moon?"
NASA says the best time for viewing is when the moon is on the horizon. Because full moon and perigee coincide Sunday morning (after the moon has set for the day), Saturday night, early Sunday and Sunday evening should all provide big, bright moons. The times to remember, according to the Naval Observatory: Moonrises occur at 7:45 p.m. Saturday and 8:43 p.m. Sunday; moonset is at 5:47 a.m. Sunday.
A June full moon is commonly called the Mead Moon, Rose Moon, Honey Moon or Strawberry Moon, the Naval Observatory says.
Not everyone is sold on this full moon's "super" status.
Bob Riddle, an astronomy professor at Longview Community College in Missouri, writes in a blog post that full moons fairly frequently occur within a day of the perigee.
"So a 'Super Moon' is not that unique nor worthy of the hype this one will receive," he writes.
And astronomer Phil Plait writes at Slate that this weekend's moon "will look pretty much like every other full Moon you've ever seen."