February Full 'Snow' Moon Is First of Four Consecutive Supermoons

This weekend, a full "snow" moon will grace the night sky—and will it be the first of four consecutive "supermoons."

Full moons refer to an astronomical phenomenon when the face of our natural satellite is fully illuminated by the sun, appearing like a perfect circle. This happens about once every month when the Earth is positioned directly between the sun and the moon.

Technically, full moons occur at a specific moment in time—which will be 2:34 a.m. EST on Sunday, February 9, according to The Old Farmer's Almanac. However, the moon will appear full to the untrained eye for about 24 hours either side of this time.

The full moon in February—the second of winter—is traditionally referred to as the "Snow Moon," "Storm Moon," or "Hunger Moon." These names originally derived from Native American groups living in what is now the northeastern U.S. but were later adopted by colonizing Europeans, according to Gordon Johnston's NASA blog.

Ancient peoples used the moon to track the seasons, so it's not surprising that Native Americans in the northeastern U.S. named February's one the "Snow Moon," given that the region typically experiences high snowfall during this month.

The names "Storm Moon" and "Hunger Moon," meanwhile, likely refer to the fact that bad weather is common in February, which would have made it much more difficult to hunt and find food.

The upcoming full moon is also described as a "supermoon"—a popular term for a full moon occurring when our satellite is close to its perigee, or its minimum distance from the Earth.

"The term itself is of no scientific value: astronomers prefer to call it
perigee full moon, but undoubtedly 'supermoon' is by far a much more charming name," Gianluca Masi, an astronomer from The Virtual Telescope Project, told Newsweek.

According to Masi, the moon will be located around 225,000 miles from the Earth when it is full this weekend. As a result, it will be around 7 percent larger and 10-15 percent brighter than an average full moon.

However, most people will not be able to recognize these subtle differences in the moon's size and brightness.

"Most people—including experienced stargazers—cannot tell the difference between a supermoon and any other full moon, because full moons are seen only once every month, and you cannot compare one to another directly," Rick Fienberg, a spokesperson for the American Astronomical Society, told Newsweek.

"The 'moon illusion' where the moon looks bigger closer to the horizon than higher in the sky—where it's actually a little bit closer to the observer and should therefore appear bigger—is much easier to see," he said.

Supermoon
The last supermoon of 2019 is seen above Los Angeles on March 20, 2019. FREDERIC J. BROWN/AFP via Getty Images

The term "supermoon" was actually defined, quite arbitrarily, by the astrologer—not astronomer—Richard Nolle as any full moon that occurs when our natural satellite is within 10 percent of its perigee on a given orbit.

"That last part of the definition, 'on a given orbit,' is critical, because the moon's perigee—and apogee, i.e., farthest distance from Earth—changes from orbit to orbit due to gravitational perturbations by the sun, Earth, and other solar system bodies," Fienberg said.

"If you want to be true to Nolle's arbitrary definition in any given year, you have to make sure you do the corresponding calculations with the most up-to-date values of the Moon's orbital parameters."

The best times to see the full moon this weekend will be when it rises at sunset and falls at dawn, according to Masi. (The exact time of moonrise and moonset will vary slightly depending on where you are. Check the timings for your area here.)

"During the twilight, the residual solar light scattered all around by our atmosphere allows us to admire the scenery, while the full moon rises or falls on the horizon," he said. "At night, the full moon is very bright, almost dazzling, compared to the darkness of the landscape."

"At its rise, the moon appears behind monuments and elements of the landscape, generating the feeling that its disk is larger than usual, but this is just an optical illusion, due to the presence of those terrestrial elements in the line of sight, giving grounds for comparison," he said.

According to astronomer Fred Espenak—who has created a table of supermoons—the next three full moons after the "Snow Moon," in March, April and May, will all be supermoons.

February Full 'Snow' Moon Is First of Four Consecutive Supermoons | Tech & Science