How and when to watch May’s blue moon

A blue moon will reach its peak on the night of May 30-31, 2026, making it visible across much of the world. This rare event, occurring roughly every two to three years, is significant for skywatchers and astronomy enthusiasts. Despite its name, the moon will appear its usual silvery white or golden hue.

The upcoming blue moon is a calendar blue moon, meaning it is the second full moon in a single month. It will peak at 4:45 a.m. ET on May 31, just before sunrise, according to EarthSky. The moon will be at its farthest point from Earth during this event, classifying it as a micromoon, with an approximate distance of 252,334 miles (406,093 km), slightly farther than its average distance.

Unlike the myth that the moon will turn blue, it will appear normal in color. The phrase ‘blue moon’ historically referred to rare or impossible events, but the current term describes the calendrical occurrence. The event is notable because it occurs about every two to three years and is the second full moon in a calendar month, with the last occurring in 2023.

Why It Matters

This event provides a unique opportunity for skywatchers to observe a rare lunar phenomenon, which is often associated with cultural and folklore significance. It also marks a notable astronomical occurrence, as the full moon coincides with its farthest orbit point, making it a micromoon. For many, it’s an ideal time for moon photography and stargazing.

Background

The blue moon phenomenon occurs due to the mismatch between the lunar cycle (about 29.5 days) and the calendar month, leading to occasional months with two full moons. The last calendar blue moon was in 2023, which was a supermoon, not a micromoon. The next calendar blue moon will be in 2037. Historically, the term ‘blue moon’ has evolved from describing impossible events to its current lunar meaning, with rare atmospheric conditions occasionally causing the moon to appear blue, such as after volcanic eruptions.

“The moon will be at its farthest point from Earth during this event, making it a micromoon, but it will still look similar to any other full moon to the naked eye.”

— Dr. Pamela Gay, senior scientist at the Planetary Science Institute

“The moon will peak at 4:45 a.m. ET on May 31, just before sunrise.”

— EarthSky

What Remains Unclear

It is still unclear how many viewers will be able to see the moon clearly due to weather conditions or light pollution in different regions. Additionally, the atmospheric conditions that could cause the moon to appear blue are rare and unpredictable, so the moon is expected to appear its usual color.

What’s Next

Following this event, the next notable lunar occurrence will be the seasonal blue moon on August 19, 2027. Astronomers and skywatchers are encouraged to prepare for optimal viewing conditions on the night of May 30-31, with some regions seeing the moon at its fullest early on May 31.

Key Questions

What is a blue moon?

A blue moon is the second full moon in a calendar month or, in some cases, the third of four full moons in a season. The current event is the calendar blue moon, which happens roughly every two to three years.

When is the best time to view May’s blue moon?

The moon will peak at 4:45 a.m. ET on May 31, 2026. For viewers in the Americas, the moon will be brightest the night of May 30, while in Australia, New Zealand, and parts of Asia, the brightest view will be on the night of May 31.

Will the moon appear blue in color?

No. Despite its name, the moon will appear its usual silvery white or golden hue. The term ‘blue moon’ refers to the timing of the full moon, not its color.

Why does the moon sometimes appear blue?

The moon can appear blue when atmospheric particles like smoke or dust are present, typically after volcanic eruptions or large fires. Such occurrences are rare, and there are no indications this will happen during this event.

Source: Google Trends