Blue Micromoon: How to Watch This Rare Celestial Event

A rare blue micromoon is set to appear this weekend, offering skywatchers a special lunar event combined with a bright star appearance. The full moon, which follows the first full moon of the month on May 1, qualifies as a blue moon because it is the second full moon in a single month, a phenomenon that happens about every two to three years. This one is also a micromoon, meaning it occurs near the farthest point in the moon’s orbit from Earth, making it appear slightly smaller and dimmer than usual.

According to astronomers, the moon will be about 252,360 miles away from Earth during the event, compared with a much closer supermoon, which can appear noticeably larger and brighter. In this case, the difference will be subtle. The moon is expected to look about 6% smaller and 10% dimmer than an average full moon, a change that most people may not notice without careful observation or comparison.

Adding to the spectacle is Antares, one of the brightest stars in the night sky and the red supergiant that marks the heart of the Scorpius constellation. For viewers in parts of the Southern Hemisphere, including Argentina, Chile, New Zealand, eastern Australia, sections of Antarctica and nearby islands, the moon will pass in front of Antares, briefly hiding it from view in a rare occultation. For observers in other parts of the world, Antares will remain visible near the moon but will not disappear.

The event is expected to be especially impressive in locations south of the equator across the Pacific. Astronomers and stargazers in those regions will get the best view of the moon-star alignment. A live webcast from Italy will also share the moment with viewers online.

Despite the name, a blue moon does not actually appear blue. The term refers only to the uncommon timing of two full moons within the same calendar month. The combination of a blue moon, a micromoon and a close encounter with Antares makes this weekend’s lunar display a rare three-part astronomical event.

For skywatchers, the show offers a chance to see the familiar full moon in an unusual context: farther from Earth, slightly smaller in appearance, and paired with one of the night sky’s best-known stars. While the visual differences may be subtle, the event stands out as a notable reminder of the rhythms and geometry of the Earth-moon system.