Sky-watchers across the globe Monday watched the second “supermoon” of the season appear in a blaze of color.
The second of four so-called supermoons—which are slightly larger in apparent size than on average—was captured looking its biggest while close to horizon.
A supermoon occurs when a full moon is closer to Earth than on average. The moon’s orbital path around the Earth is elliptical, so there’s a day each month when it’s at it closest. However, only when that day coincides with full moon is it popularly called a supermoon.
An astrological, not astronomical term, a supermoon refers to a full moon that occurs within 90% of the moon’s closest approach to Earth in a given orbit. The proper astronmical term for a supermoon is a perigee full moon.
The “Sturgeon Moon” became 100%-lit by the sun while 222, 023 miles (357,311 kilometers) from Earth. A supermoon appears about 14% larger and 30% brighter than usual.
August’s full moon is usually called the “Sturgeon Moon” in the northern hemisphere. It’s named after the seasonal appearance of the sturgeon fish that are found in the Great Lakes in North America at this time of year.
Other popular names for August’s full moon include the “Grain Moon,” “Corn Moon,” “Lynx Moon,” “Lightning Moon” and “Dispute Moon.”
The season’s final full moon—also a supermoon—will rise on Wednesday, August 30, 2023. It will be called a “Blue Supermoon” because it will be the second full moon in a calendar month, something that happens where there are 13 full moons in one calendar year. However, a fourth and final supermoon will occur on September 29—the “Harvest Supermoon.”