Subaru sees "First-Light"!

On January 28th, 1999, the director and staff at Subaru Telescope presented First Light results for their new 8.3-meter telescope on Mauna Kea, Hawaii. This page presents two of those images. Here is a link to the original press release.

THE ORION NEBULA. This is an infrared image of the the famous Orion nebula (Messier 42), located 1500 light years away. At the center of the image is the Trapezium, a group of four bright stars. Many stars seen around the Trapezium are young stars embedded in the Orion molecular cloud located behind the Orion nebula. Many of them are seen only at infrared wavelengths. Above the Trapezium, a butterfly-like red feature is seen in the image, containing the Kleinman-Low (KL) nebula which is deeply embedded in the Orion molecular cloud. At the center of the KL nebula is a star called IRc2, which is in the process of forming. This star is believed to be 30 times more massive than the Sun, and its activities are the cause of the big butterfly feature. Blue, faint, and diffuse emission extending over the entire region is due to hot gas ionized by strong ultraviolet radiation emitted by the Trapezium stars. The bright bar seen in the lower left part of the image is an ionization front.

This false-color image was synthesized from three images taken with J (1.25 micron), K' (2.15 micron), and H2-line (2.12 micron, narrow band) filters, assigning blue for J, green for K', and red for H2-line images. Nine images of contiguous fields were obtained with CISCO, which has a 2 arcmin by 2 arcmin field of view, and were combined to make this image. Some ghost (false) images from very bright stars are seen.

THE ORION KL REGION. This is an enlarged image of the region around the Kleinman-Low nebula in the Orion cloud located 1500 light years away. This image is taken in light at 2.12 micron, which is emitted by warm molecular hydrogen gas with an absolute temperature of 2000 K. This is Subaru's first image in the light of a single emission line, demonstrating its high resolution capability. Although not seen in this image, at the center of the giant butterfly-like feature is IRc2, a star 30 times more massive than the sun which is in the process of forming. A strong wind with a speed of more than 100 kilometers per second is blowing out from IRc2, evacuating the butterfly-like cavity and allowing infrared light to escape. Many finger-like features are seen radially emanating from the Orion KL region, produced when the strong stellar wind from IRc2 collides with the surrounding cold material, heating it to around 2000 K and causing the hydrogen molecules to emit light.

The vertical and horizontal stripes and moire patterns are artifacts of the initial data processing. Two separate images were combined to produce this image, and the black and white dots are a result of this process.