Largest-mirror telescope brings infrared universe to light

The Orion nebula shines with the birth of stars in these infrared (IR) images, among the earliest taken by the Subaru telescope when it achieved first light in January. The main photo is a false-color image consisting of three exposures taken with 1.25-, 2.12- and 2.15-µm filters. Surrounding the Trapezium-the four bright stars in the center-numerous young stars shine through the nebula`s dust only in the IR. The blue glow of the star-forming nebula-located 1500 light-years from Earth in th

Th Orion

The Orion nebula shines with the birth of stars in these infrared (IR) images, among the earliest taken by the Subaru telescope when it achieved first light in January. The main photo is a false-color image consisting of three exposures taken with 1.25-, 2.12- and 2.15-µm filters. Surrounding the Trapezium-the four bright stars in the center-numerous young stars shine through the nebula`s dust only in the IR. The blue glow of the star-forming nebula-located 1500 light-years from Earth in the constellation Orion the Hunter-comes from hot gas, ionized by strong ultraviolet radiation that the Trapezium stars emit.

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Two images, taken at 2.04 and 2.12 ?m, of the red and orange region in the upper right corner of the photo combine to show a cloud shaped by the solar wind from a star 30 times as massive as the Sun, which is still in the process of forming. The finger-like regions are produced when the wind strikes cold matter, heating it to about 2000 K and causing hydrogen molecules to glow (inset).

The Subaru telescope (Subaru is the Japanese name for the stars Westerners call the Pleiades or the Seven Sisters) is owned by the National Astronomical Observatory of Japan (NAOJ) and sits atop Mauna Kea on the Big Island of Hawaii. With an effective surface diameter of 8.2 m, it is the largest optical-infrared telescope in the world and the largest monolithic mirror; the European Southern Observatory`s Very Large Telescope in Chile consists of four telescopes, each 8.1 m across.

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Through adaptive optics, a set of 261 computer-run actuator arms control the shape of the extremely thin-20-cm-thick-mirror, currently coated with a 100-nm-thick layer of aluminum. That coating will eventually be replaced with silver, which is more suitable for working with IR light. The telescope, designed to work from 300 nm in the UV to 30 ?m, will use a variety of cameras and spectrographs for viewing in the mostly unexplored IR, where objects cooler than the Sun become visible. These images were taken with Subaru`s Cassegrain focus and a cooled IR spectrograph and camera.

"We are quite happy," Subaru director Norio Kaifu said of the images from the opening phase of the project. "We got very good results for the very first time."

Project scientists will run tests of the instruments until March 2000, when Subaru will be made available to astronomers around the world.

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