Look! Up in the Sky! It’s Supermoon!

Get ready for the second supermoon of the summer on Sunday, August 10. The moon is expected to be the biggest and the best of the five total supermoons taking place in 2014.

July 22, 2013 Supermoon. Credit: Arches National Park via Flickr

Credit: Arches National Park via Flickr

The term “supermoon” comes from the moon being ever-so-slightly closer to the Earth than at any other time of year, while aligning with the Earth and Sun. As a result, the Moon will appear much larger than normal, especially on the horizon.

Just as the Earth revolves around the Sun, making the trip in just over 365 days, our Moon revolves around the Earth once every 28 to 29 days. Its path is not a perfect circle, but instead an oval-shaped ellipse, meaning that at one point every month, the Moon is closer to the Earth than any other time. This time of its cycle is known as perigee.

Supermoon over Dallas. Credit: Robert Hensley via Flickr

Supermoon over Dallas. Credit: Robert Hensley via Flickr

Every 14 months, the Moon’s perigee lines up with its full phase, when the Sun, Earth and Moon are in a row. To astronomers called this the “perigee-syzygy.” To regular folks, it’s been given a much catchier moniker: “supermoon.”

During the supermoon, the moon appears in the sky to be up to 14 percent larger and 30 percent brighter in the sky. The combined effect of the Sun and the Moon’s gravity causes the ocean’s tides to increase, sometimes by as much as 15 to 20 percent. At the surface, this leads to waves that area few inches higher during the supermoon.

Legends surrounding supermoons abound.  No, super-werewolves are not expected to roam the Earth! Some claim that the event is to blame for doom and gloom. For example, five ships ran aground along the British coast in 2011 after the increase in tides pushed a spit of land underwater. Other events have been claimed to be related to the supermoon, but there is no scientific proof. For example, the 2011 Japan earthquake occurred on the day of the supermoon, as did the December 2004 Indonesia earthquake.

If you miss the August 10 Supermoon, you’ll have another chance to see another soon: September’s Full Moon will also be a supermoon.



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