Prime Focus Spectrograph Receives Hawaiian name ʻŌnohiʻula

December 23, 2025
The University of Tokyo Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI)

Figure 1: Artificial image of Ōnohiʻula PFS. (Credit: Kapuaonaona Roback/'Imiloa Astronomy Center of Hawai'i/PFS collaboration)

The Prime Focus Spectrograph, an international project led by the University of Tokyo Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), and includes the National Astronomical Observatory of Japan (NAOJ), was formally gifted the Hawaiian name ʻŌnohiʻula by Hawaiian language and cultural expert and University of Hawai’i Professor Larry Kimura on November 19.

ʻŌnohiʻula embodies the idea of perceiving the realm of our origins, honoring the people and land of Hawaiʻi and expressing a commitment to exploring the Universe together with the local community.

The Prime Focus Spectrograph (PFS) is a wide-field, multi-object spectrograph installed at Subaru Telescope’s prime focus. At maximum capability, PFS can observe approximately 2400 celestial objects simultaneously within a wide field of view and obtain their spectra across an extensive wavelength range—from visible to near-infrared light—in a single exposure. Since it began full science operations in March 2025, PFS has been opening a new era of large-scale spectroscopic surveys in cosmology, galaxy evolution, the structure of the Milky Way, and will help uncover the origins of dark matter and dark energy.

Kavli IPMU Professor and PFS Collaboration Principal Investigator Hitoshi Murayama, Kavli IPMU Visiting Senior Scientist and NAOJ Professor Naoyuki Tamura, and representatives including ʻImiloa Astronomy Center of Hawaiʻi Astronomer-in-Residence Dr. Devin Chu, and Subaru Telescope Public Information Outreach unit Christian Wong, took part in the naming event.

The name ʻŌnohiʻula is rich with meaning. The word ōnohi refers to "what one perceives from their sight," an idea inspired by the role of the telescope’s prime focus—where PFS is mounted—as a kind of "eye." The component ʻula means "red," evoking both the countless redshifted galaxies that ʻŌnohiʻula PFS will observe and the studies of the early Universe and galaxy evolution—our cosmic origins—that these observations will enable.

"The name ʻŌnohiʻula represents the spectrum of the rainbow that we can see here, on the ground on earth, and the eye of the PFS and in particular the color red, a sacred color which is associated with what we call the heavens in Hawaiian culture," said Kimura.

Figure 2: Attendees at the naming ceremony. From left: Professor Naoyuki Tamura (Subaru Telescope), who has served as the PFS Project Manager; Professor Hitoshi Murayama (Kavli IPMU, University of Tokyo/University of California, Berkeley), who leads the PFS collaboration; Professor Larry Kimura (University of Hawaiʻi at Hilo); Dr. Devin Chu (ʻImiloa Astronomy Center of Hawai’i), a Hilo-born astronomer; and Christian Wong, of the Subaru Telescope Public Information Outreach office and Executive Director of the Hawaii Science and Technology Museum. (Credit: NAOJ)

This naming reflects a deep resonance between state-of-the-art scientific exploration and perspectives grounded in Native Hawaiian knowledge. It symbolizes Subaru Telescope’s commitment to honoring both the global importance of astronomical research and the profound cultural significance of Maunakea for the people of Hawaiʻi.

"It's very important for Subaru Telescope to connect to our culture here in Hawaiʻi and the way we can do that is through this name," said Kimura.

"ʻŌnohiʻula represents not just a powerful new eye on the Universe, but a commitment to conduct that exploration in conversation and collaboration with the people and place of Hawaiʻi," said Tamura, who has long served as PFS Project Manager. "We are honored to carry this name forward as ʻŌnohiʻula PFS opens a new era of discovery."

"Our instrument received a beautiful name in Hawaiian language. It represents the science of PFS very well. I have a renewed resolve to make sure we will produce exciting science with ʻŌnohiʻula PFS just as this name indicates," said Murayama.

The instrument will be referred to as ʻŌnohiʻula PFS in scientific publications and press releases, expressing Subaru Telescope’s ongoing respect for Hawaiian culture and its people.