Hokule‘a, Arcturus in the constellation Bootes, is the zenith star for Hawaii, passing above the Kau desert on Hawaii island.

Armchair researchers have speculated that Hokule‘a, the fifth brightest star in the sky following the sun, Sirius, Spica and Alpha Centauri, may have been an object that led early oceanic mariners in the direction of the Hawaiian Islands as they migrated from islands in the South Pacific. Based upon similar language traits, researchers believe that the Hawaiian Islands’ original settlers migrated north from the Marquesas Islands.

The location of the Marquesas to the southeast of Hawaii would allow for a natural westward drift by canoes migrating north under the influence of the tradewinds.

Along with Hokule‘a, the star Hikianalia, Spica in the constellation Virgo, and Hokupa, Regulus in the constellation Leo, make up the Spring Triangle. Hikianalia rises a little south of Fatu Hiva in the Marquesas Islands making it a zenith star for that archipelago. Perhaps zenith stars were used to mark the latitudes of significant islands within Oceania, marking the sailing pathways between archipelagos.

Voyaging traditions

More conclusive evidence of Polynesian voyaging traditions was found on Huahine island in 1973 by Yosihiko Sinoto of Bishop Museum.

While restoring sites on Huahine an unexpected discovery was made at Vaito‘otia, which was being developed into 34 thatched roof bungalows that would become the Hotel Bali Hai. Workers there found whale bone artifacts. Because Polynesians did not hunt whales, they were thought to be from a washed-up whale carcass. One bone that astonished Sinoto was identical to a Maori patu, or whale-bone hand weapon, never seen before outside of New Zealand.

Sinoto had always considered Vaito‘otia an unremarkable location not suitable for settlement, but in addition to the whale bone artifacts, adzes, fish hooks and ornaments, all the products of a major coastal settlement were found there. He even unearthed the foundation of a fare potee, a traditional meeting house.

But the most compelling find came years later. While dredging a pond and using the sand to level a pad for a tennis court, workers discovered artifacts believed to be from a 65-foot-long voyaging canoe: a 12-foot steering paddle, two 23-foot-long canoe planks, an intact 35-foot mast and a 9-foot wooden bow or stern piece.

Hidden innovations

The star Hikianalia, or Spica, is a part of the constellation of Virgo. Within Virgo, sitting between Hikianalia and Hokupa (Leo) in our chart, is where astronomers observe the Virgo Cluster, which contains more than a thousand galaxies that are all gravitationally bound together. The Virgo Cluster’s massive gravity is slowly pulling the Local Group galaxies, including the Milky Way, toward the cluster. Sitting near the center of the Virgo Cluster is the massive M87 galaxy.

Sitting at the center of M87 is a supermassive black hole that has intrigued astronomers for years; it became the first black hole to be imaged through a new innovative technique. In 2017, astronomers around the world used submillimeter radio telescopes, including two of the telescopes atop Mauna Kea, to create a telescope array (equal to the size of Earth) to collect the first image of this black hole’s event horizon. The amount of data collected through this project, the Event Horizon Telescope, took two years to process and the image was released April 10.

Now the black hole in the center of M87 has been given the name Powehi.

Evening observations

Stretching over our heads at 8 p.m. will be the navigational starline of Kaiwikuamo‘o, the Backbone. This full starline stretches across the sky from Hokupa‘a, the North Star, to Hanaiakamalama, the Southern Cross, which will be visible in Hawaii right after sunset until 1 a.m. in early May. The red planet Mars remains in the northwestern region of our early evening sky.

Lahaina Noons

Hawaii is fortunate to experience unique events called Lahaina Noons. When this occurs, the sun rises to the exact center of the sky (known as the zenith) and objects that have smooth sides will cast no shadow on the ground. Slight changes in latitude mean that Lahaina Noon will fall on different dates across the state, but we will all experience two Lahaina Noons — one before the summer solstice and one after.

In Honolulu, the first Lahaina Noon will be 12:28 p.m. May 27 and the second will be 12:37 p.m. July 16. In Hilo, the first Lahaina Noon will be 12:16 p.m. May 18 and the second will be 12:26 p.m. July 24.

May Skywatch by on Scribd

Chad Kalepa Baybayan (Kalepa.Baybayan@hawaii.edu) serves as navigator-­in-residence and Emily Peavy (Emily.Peavy@hawaii.edu) as planetarium technician support facilitator at the ‘Imiloa Astronomy Center of ­Hawaii, a center for informal science education at the University of Hawaii at Hilo showcasing astronomy and Hawaiian culture as parallel journeys of human exploration.