The Super Blue Moon of August 31st will be orange!

You may have already heard about it: On Thursday, August 31, the full moon will not only be a “super moon,” but also a so-called “blue” moon! On paper, it’s something to dream about, but in reality, it’s not enough to cut off three legs from a duck… First because the term “blue moon” only qualifies the fourth quarter moon. The duration of the lunar cycle is actually a little less than a month, it is about 29.5 days. So sometimes it happens that the second full moon occurs during the same month. But its color will not be distinct, except that it can show a slightly orange hue.

The moon will be as blue as orange!

And for good reason: the Moon’s path around the Earth is elliptical. So there are differences in distance. We talk about aphelion when it is at its farthest point from Earth (about 405,000 km), and about perihelion when it is at its closest point (360,000 km). On Thursday, the full moon will be at perigee and low in the sky. However, when light enters the atmosphere, it is made up of different wavelengths, each of which corresponds to a specific color. Shorter wavelengths, such as blue and violet, are more scattered by air molecules than longer wavelengths, such as red and orange.

On August 31, light reflected by the moon will have to pass through a thicker atmosphere, which will result in greater scattering of shorter wavelengths. This is why the red and orange colors will be more visible. And since the Moon will be closer to Earth, it will also appear 14% larger and 30% brighter! Impressive numbers, but the difference is barely visible to the naked eye… In short, a “super blue moon” would not be synonymous with an impressive spectacle that evening. On the other hand, beware of the tides, which are much higher at perigee!