Did you see the year’s biggest full Moon rise this week?
Looking to the east at dusk on Tuesday, June 14, 2022 was what you should have been doing to get eyes-on with the “Strawberry Moon”—the final full Moon of spring and also the year’s biggest, brightest and best “supermoon. ”
Here’s what it looked like from around the world:
Although it’s usually called the “Strawberry Moon” because the soft fruit is in season in the northern hemisphere June’s full Moon is also called the “Hot Moon,” Mead Moon” and “Rose Moon.”
A “supermoon” is said to occur when our Moon moves closest to the Earth in its elliptical orbit while in its “full” phase. It thus looks slightly larger and brighter than usual.
May’s full Moon will be the biggest and best “supermoon” of 2021, but the next full Moon—on April 26, 2021—can still be called a “supermoon” because it occurs within 90% of its closest approach to Earth in a given orbit. It will look about 6% bigger than the “average” full Moon, and up to 30% brighter.
There’s no hard and fast definition of what a “supermoon” is, with some calculations meaning there are four in 2022 and others just two. However you define them there are certainly two supermoons in 2022—in June and July—with this week’s “Strawberry Moon” the closest to Earth, so the biggest in the sky.
Not that the full Moon looks much larger purely because it’s a supermoon. The difference is very slight, with a supermoon only appearing about 14% larger than the smallest (farthest) full Moon of the year.
The apparent diameter of the Moon is only 0.5º. The celestial sphere around our planet is 360º and from any one place on Earth you can see 180º—the visible night sky (the rest is below the horizon). So 0.5º isn’t much. It’s actually just one 72,000th the size of the sky.
The apparently large size of a rising full Moon is down to something called the “Moon illusion.” Whether you watch a full Moon rise behind a tree, between buildings or above the roofs of houses, our brains make comparisons between them and the size of the Moon. Your brain makes the Moon look huge. It’s an optical illusion that lasts for only a few minutes when the Moon is close to the horizon.
Either way, the night of the full Moon is the only opportunity of the month to see the full disk of the Moon appear on the horizon during dusk. That’s because it rises about 50 minutes later each night so either rises during daylight or darkness either side of “full Moon night.”
The Moon always looks at its delicate best during moonrise and moonset close to the time of it being at its “full” phase. For most of the night the full Moon looks like it always does—bright and white—though for about 15 minutes as it rises in the east it appears orange, turning to a pale yellow as it rises higher into the sky.
The reason for the Moon’s color as it rises is something called Rayleigh scattering. Earth’s atmosphere contains oxygen and nitrogen molecules that absorb some wavelengths of light more effectively than others.
Colors in the sun’s light with short wavelengths, such as blue, strike more particles and are therefore more often absorbed. They scatter more easily, which is why the sky is blue during the day. Colors with longer wavelengths, such orange, more easily pass through the uninhibited atmosphere.
When you look at moonrise you’re looking across the planet so you’re looking through a lot of atmosphere. So Rayleigh scattering is intensified, with orange dominating the light that makes it to your eyes.
The next full Moon is the “Buck Moon,” which rises on Wednesday, July 13, 2022. It will also be a “supermoon,” albeit not quite as close as the “Strawberry Moon” so slightly smaller in the sky.
Wishing you clear skies and wide eyes.