Astronomy Essentials

What is a micromoon? We have 2 coming in May

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Deborah Byrd

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April 29, 2026

Two full moons side by side. The right one is distinctly smaller. — View at EarthSky Community Photos. | Our friend Soumyadeep Mukherjee shared this comparison of a full supermoon (May 2021) and a full micromoon (December 2021). He wrote: “The apparent diameter of this supermoon was 33.9 arcminutes. Meanwhile, the micromoon appeared only 29.7 arcminutes large in the night sky.” Thank you, Soumyadeep!

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What’s a micromoon?

A micromoon is a full or new moon that occurs when the moon is roughly at its farthest from Earth in its orbit.

The moon takes about a month to orbit Earth once (that’s where the word “month” or “moon-th” comes from). And the moon’s orbit around Earth isn’t a perfect circle. So the moon has a nearest point (perigee) and a farthest point (apogee) each month.

When we have a full moon around the time of apogee, that’s a full micromoon.

There’s no strict definition of how close to apogee the moon should be to be called a micromoon. That can lead to some disagreement over what is and isn’t a micromoon! For instance, in 2026, according to Fred Espenak’s AstroPixels website, we have a micromoon with the full Flower Moon of May 1 … but not all sources consider this quite distant enough to be a micromoon.

For example, Timeanddate.com says the next micromoon is the Blue Moon of May 30-31. Astropixels also lists this as a micromoon. In fact, the full moon at the end of May will be 2026’s most distant full moon of the year. It’ll be 252,360 miles (406,135 kilometers) away, in contrast to the moon’s average distance of 238,900 miles (384,472 km).

Both sources agree the full Strawberry Moon of June 29 is a micromoon. So there are either two or three micromoons in a row this year, depending on which source you use.

The moon never stops moving in orbit. So its exact distance from Earth changes continuously. But it’s safe to say that a full micromoon appears about 12-14% smaller than a full supermoon (an exceptionally close full moon). A full micromoon appears about 7% smaller than a full moon at an average distance.

Can a new moon be a micromoon? Sure! There’s only one new micromoon in 2026. It’ll come on December 9. That new micromoon is the most distant new moon this year. It’ll lie 251,460 miles (404,687 kilometers) away.

2 full moons, white with black splotches on them, the left one noticeably bigger. — View at EarthSky Community Photos. | Krittiman Debnath of India submitted this composite image and wrote: “Here’s a side-by-side comparison of the supermoon on August 19, 2024, and the micromoon on April 12, 2025. They were both captured using my Celestron PowerSeeker 60AZ. Both images were taken with the same setup.” Thank you, Krittiman. You can easily see the size difference of a full supermoon and a full micromoon. However, most people won’t notice a size difference to the eye, but supermoons do look brighter.

2 full micromoons in 2026? Or 3?

Again, as with supermoons – which are exceptionally close moons – there are no hard and fast rules as to what constitutes a micromoon. The late Fred Espenak’s great Astropixels website lists three full micromoons for 2026 (May 1, May 31 and June 29). And it defines micromoons like this:

In contrast to the supermoon there is the micromoon. When either the new moon or full moon phase occurs near apogee (within 90% of its greatest distance to Earth in a given orbit), the moon subtends its smallest apparent diameter as seen from Earth. This phenomenon, referred to as a apogee syzygy or apogee new/full moon, is popularly known as a micromoon. Using the definition above and applying it to the moon’s mean apogee and perigee distances results in a mean limiting distance of 401,293 km for a micromoon.

Meanwhile, Timeanddate.com lists just two full micromoons for 2026 (May 31 and June 29). It defines micromoons and supermoons like this:

Micromoon: A full moon or new moon that takes place when the center of the moon is farther than 405,000 kilometers (251,655 miles) from the center of Earth.

Supermoon: A full or new moon that occurs when the center of the moon is less than 360,000 kilometers (223,694 miles) from the center of Earth.

Bottom line: What is a micromoon? It’s a full or new moon near its farthest from Earth for the month. Depending on your definition, 2026 has either two or three full micromoons.

Read: 1st May full moon is a Flower Moon and micromoon

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April 29, 2026

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Astronomy Essentials

Deborah Byrd

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About the Author:

Deborah Byrd (asteroid 3505 Byrd) helps edit EarthSky.org and is a frequent host of EarthSky videos. Deborah created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Prior to that, she had worked for the University of Texas McDonald Observatory since 1976, and created and produced their Star Date radio series. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named in her honor in 1990, a Public Service Award from the National Science Board in 2003, and the Education Prize from the American Astronomical Society in 2020. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.