On July 9, those who are blessed with a night of clear skies during the stormiest month of the year will be able to see the Full Thunder Moon dominate the sky alongside Saturn. The moon will be completely full at 12:07 a.m. EDT(0407 GMT) on Sunday (July 9). For observers on the U.S. East Coast, the nearly full moon will rise about 4 hours before the moon reaches peak fullness on Saturday evening. Saturn will rise in the east a little sooner, about 6:30 p.m. local time.
When & where to see it
Skywatchers in the southern U.S. will have a better view of the full moon as it rises even higher in the sky. For example, in Miami, the moon’s maximum altitude is 48 degrees above the horizon. The moon will rise at 7:31 p.m. on July 8, reach full phase at 12:07 a.m. July 9, and set at 5:57 a.m. local time.
Those in Sydney, Australia, will miss the full moon’s peak, with the moon rising about 3 hours after it reaches full phase at 2:07 p.m. local time on July 9. It will set again at 7:03 a.m. on July 10 after reaching a maximum altitude of about 74 degrees.
To find out when and where the moon will be out at your location, check out this handy moonrise and moonset calculator.
How the Thunder Moon got its name
The traditional full moon names, like Thunder Moon, reflect the seasons in many temperate Northern Hemisphere climates. In many parts of the continental U.S., thunderstorms are more frequent in July as the weather heats up, so Thunder Moon was an apt name for some Native American cultures.
Yet there was and is a lot of variety in the associations Native Americans made. Algonquin speakers called it the Buck Moon, for the period when the antlers on deer start growing. In the Pacific Northwest, the Tlingit called it the Salmon Moon.
Given that crops start to ripen in July as well, it’s no surprise that the Cherokee called it the Ripe Corn Moon, or that among European colonists it was called the Hay Moon. Europeans had another name for the July full moon: Mead Moon, because it appeared at the same time as larger honey yields. (Mead is an alcoholic drink made from fermenting a mix of honey, yeast and water.)
In the Southern Hemisphere, the moon names reflect the reversal of the seasons. For example, the Māori of New Zealand called the lunar month of June-July Hongonui (or Hōngongoi) and paired it with the phrase “Man is now extremely cold and kindles fires before which he basks,” according to the Encyclopedia of New Zealand. The day of the full moon was called Rākau-nui.
Whatever you want to call it, be sure to look up to see the full moon on July 9. And if you happen to miss the moon at its fullest, don’t worry – it’ll appear pretty much full on July 8 and July 10 as well.
The phases of the moon are determined by how much of the moon’s visible face is illuminated by the sun.