WASHINGTON, July 11, 2014 — The first supermoon of the summer will illuminate the sky tomorrow, July 12. It will also appear full, and bigger than usual, tonight.
Astronomers define this particular event as a perigee full moon. It is when the moon’s orbit brings it closest to the earth, making it appear larger than usual. When it is at its furthest point from the earth, it is in apogee.
This year, a perigee full moon will appear on July 12, August 10 and again on September 9. Although the full moon tomorrow will be among the brightest of the year, true stargazers are most excited about the August 10 showing, when the moon will be even closer to the earth than it will be tomorrow. That full moon will be the brightest of 2014.
Supermoons are regular occurrences, happening every 13 months and 18 days, when the moon’s orbit brings it into perigee. The moon in Perigee is around 50,000 km closer than when it is furthest away, or in apogee.
Supermoons are awe inspiring. They can appear to be as much as 14 percent larger than a regular full moon, and 30 percent brighter.
A perigee full moon can also impact tides, rising the high tide a few inches above normal.
You can visit the Farmer’s Almanac to see the full moon calendar with time/date for your city here.
To see the supermoon, hope for clear skies, and look up.
Thanks to readers Kurt Iben