Bishop Museum’s J. Watumull Planetarium shares May 2026 Astronomical Phenomena

Bishop Museum, the State of Hawaiʻi Museum of Natural and Cultural History, shares news of two astronomical phenomena occurring in the second half of May. Educators from the Museum’s J. Watumull Planetarium note that people on Oʻahu will experience a Lahaina Noon on Tuesday, May 26, 2026, and all major Hawaiian Islands will see a Blue Moon on Saturday, May 30, 2026.

Lahaina Noon

“Twice a year, in May and July, the sun passes directly overhead us in Hawaiʻi. On these two days, the sun will be above us at a 90 degree angle to the horizon and any upright object, such as a flagpole, won’t have a shadow,” said Romee Wizza Gaoiran, Bishop Museum Planetarium manager. “This phenomenon only occurs in the tropics and as Hawaiʻi is the only U.S. state in the tropics, we’re the only state that experiences Lahaina Noon.”

While the contemporary term “Lahaina Noon” is often used today, an older term in ʻŌlelo Hawaiʻi (Hawaiian language) for this phenomena is “kau ka lā i ka lolo,” which can be understood to mean “the sun rests upon the brain.” 

Mary Kawena Pukui (1979) shares in the book “Nānā I Ke Kumu, Volume 1,” that the phrase references high noon, when the sun is directly overhead and the shadow retreats into the body, a time of great spiritual significance when certain rituals might be conducted. High noon “was thought of as a time of great mana (spiritual power),” according to Pukui.

Lahaina Noon has also been called “Shadowless Noon.” On Tuesday, May 26, those on Oʻahu can experience the phenomena for about 10 minutes when the sun is at its highest point in the sky. Other Lahaina Noon dates and times, for locations throughout Hawaiʻi, can be found on Bishop Museum’s webpage: BishopMuseum.org/LahainaNoon.

Blue Moon and the “colors” of the moon

“Although it would be really neat to see, during a Blue Moon the moon isn’t actually blue, contrary to popular belief,” said Gaoiran. “Rather, a Blue Moon is when there’s a second full moon in any given month.”

The phenomenon occurs every 2-3 years and this month, a Blue Moon can be seen over Hawaiʻi on Saturday, May 30 (the first full moon this month occurred on May Day, Friday, May 1).

When the moon is observed in a different color, such as shades of red, it is usually due to a lunar eclipse — when the moon passes through the Earth’s shadow — or as a result of scattering of particulate matter in the Earth’s atmosphere.

During the Artemis II mission, astronauts were quoted as observing how “colorful” the moon was up close, with astronaut Jeremy Hansen describing the Aristarchus Plateau as having green and brown hues.

For the earthbound population, we can only ever see one side of the Moon as it is tidally locked with our planet, meaning that the moon spins around its axis once at a rate that matches the duration of its orbit around Earth. Thus, we are only ever looking at one side of the moon. Our solar system’s largest moons are also tidally locked with their planets. When a “new moon” occurs, and the moon appears dark to us on Earth, its far side is fully lit.

Bishop Museum’s J. Watumull Planetarium offers weekly daytime programming and monthly evening programs that feature Hawaiʻi’s night sky, navigation by starlight, the undersea realm, dinosaurs, and even a trivia competition! Details can be found on the Planetarium’s webpage, BishopMuseum.org/Planetarium.

The Planetarium also offers a monthly Sky Map of celestial objects visible in the Hawaiian night sky, as a free educational tool for astronomers of all ages. A PDF of the June Sky Map is attached with this release.

About the J. Watumull Planetarium

Bishop Museum’s Jhamandas Watumull Planetarium opened its doors on Dec. 12, 1961. Originally called the Kilolani Planetarium, in 2003 it was renamed the J. Watumull Planetarium and has served more than six million visitors and students over 60 years of continuous operation.

The Planetarium was instrumental in the recovery of the nearly lost art and science of traditional, non-instrument navigation in Hawaiʻi. Nainoa Thompson of the Polynesian Voyaging Society spent countless hours in the Planetarium with Will Kyselka and other Planetarium staff in the late 1970s, learning how to read the night sky. Today, the Planetarium serves 70,000 people every year, focusing on programs about Hawaiʻi and blending live and prerecorded elements within each program, as well as providing online options for those around the world to enjoy.

The Planetarium is named in honor of Jhamandas Watumull, father of the late Gulab Watumull, whose family has a long history in the community and with the Museum. The Watumulls are active supporters of Bishop Museum through many decades, with Gulab serving on the Museum’s Board of Directors from about 1999 until 2016. In addition to the Planetarium, the family’s support is reflected in the “Gulab and Indru Watumull Atrium”; the Kapa case in Hawaiian Hall; and the Volcano Observatory in the Science Adventure Center.

To learn more about the J. Watumull Planetarium, please visit BishopMuseum.org/Planetarium.