The full Moon rising Wednesday evening over the Bay Area is being called a Super Blue Moon.
Why super? Any time a full Moon coincides with the Moon’s closest approach to Earth in its 27-day orbit, that Moon is referred to as a perigean or Super Moon. The Moon at its perigee, or closest point of orbit, is approximately 226,000 miles from Earth, according to NASA. The last Super Moon was earlier this month on August 2.
Why blue? Because it’s the second full Moon in August and the third full moon this summer, a season that spans four full Moons, according to Space.com. So it’s blue by two definitions, one of which is monthly and refers to any second Full Moon in any given month. While the other definition is seasonal:
“The older definition of Blue Moon, dating back to at least the 1500s, is the name for the third full Moon in a season that has four Moons. By this definition, the full Moon in August 2024 will be the Blue Moon and this full Moon, as the last full Moon of summer, shares some of the seasonal names from my posting for the August 1 full Moon. Neither of these definitions has anything to do with the color of the Moon, so the Blue Moon will not actually look blue.”