The prime focus unit, a major component of the Hyper Suprime-Cam (HSC) prime focus camera newly installed in the Subaru Telescope on the Big Island of Hawaii, was delivered late last month by Mitsubishi Electric Corp. to the National Astronomical Observatory of Japan (NAOJ) of the National Institutes of Natural Sciences. The prime focus unit is a major component of the Hyper Suprime-Cam recently installed in the Subaru Telescope. Courtesy of National Astronomical Observatory of Japan. The HSC’s upgrade with the prime focus unit will enable the Subaru Telescope to observe dark energy and dark matter with unprecedented accuracy, Mitsubishi said. Astronomists are actively trying to determine the characteristics of dark matter and dark energy, which comprise 90 percent of the universe and are considered crucial to understanding the origin and evolution of the universe. The Subaru Telescope, which has an 8.2-m-diameter primary mirror, is noted for its high-quality widefield observations. The new HSC realizes a field that is about seven times wider than the previous prime focus camera, the Suprime-Cam, but still maintains high-resolution images. The prime focus unit helps to accurately maneuver the camera and widefield corrector lens, which together weigh about 2.2 tons, Mitsubishi said. The unit’s six actuators are capable of large load bearing and very high precision, enabling the lens and camera to be accurately positioned relative to the telescope’s primary mirror with micrometer precision and extremely smooth motion to continuously compensate for the effects of gravity deflection. The instrument rotator’s drive mechanism rotates the camera on an optical axis with smooth precision to ensure that the camera is always aligned with the diurnal rotation of the sky. Mitsubishi Electric managed construction of the Subaru Telescope, the world’s largest optical-IR telescope, which is located at the summit of the 4200-m Mauna Kea in Hawaii. The company’s revolutionary temperature control system with ellipse dome reduces atmospheric blurring. Its 261 actuators maintain the 8.2-m-wide, 20-cm-thick mirror in perfect shape. For more information, visit: www.MitsubishiElectric.com/products/space/telescopes