Context
In astronomy, analyzing the light from celestial objects is essential to understanding their nature and evolution. Spectrographs installed on telescopes enable this light to be broken down into a detailed spectrum, revealing valuable information about the composition, speed, and distance of stars. This information helps scientists explore the formation of galaxies, the distribution of dark matter, and the history of the universe.
The Prime Focus Spectrograph (PFS) is a key instrument of the Subaru 8.2-meter Japanese telescope located at Maunakea, Hawai’i. This optical/near-infrared multi-fiber spectrograph is designed to study cosmology, galactic archaeology (the study of the history and evolution of galaxies), and galaxy evolution.
The PFS uses ~2400 fibers, each ~60 meters long, which are precisely positioned on cosmological/astrophysical targets by robotic positioners. These fibers carry light to a set of four three channel spectrograph modules. The modules have a wavelength range from 0.38 µm to 1.26 µm, and an average resolving power of 3000, which is a measure of how well the spectrograph can distinguish between closely spaced spectral lines.
A consortium of more than 20 institutions worldwide contributed to design, manufacturing integration, and tests of the PFS. In particular, the Laboratoire d’Astrophysique de Marseille (LAM) managed the integration and testing phase of the spectrographs that have been manufactured essentially by Bertin Winlight, a brand of Bertin Technologies.
View of Subaru Telescope and Spectrograph Modules location. Credit: PFS project/Kavli IPMU/NAOJ
