Large Binocular Telescope Captures First Light Images

Michael A. Greenwood

A giant telescope that resembles a pair of binoculars is up and running atop Mount Graham in Graham County, Ariz., peering into a galaxy some 102 million light-years away from the Milky Way.

With its twin side-by-side mirrors measuring 27.6 ft in diameter, the device is billed as among the largest and most powerful telescopes in the world. The idea for the Large Binocular Telescope, known as LBT, was first proposed in the early 1980s, and constructing the instrument took an international team from the US, Italy and Germany.

Figure 1. This is the first of three LBT light images taken in early January. It shows a false-color rendition of the spiral galaxy NGC 2770. The image combines ultraviolet and green light, which enhances the clumpy regions of newly formed hot stars in the spiral arms. Images courtesy of Large Binocular Camera team, Rome Observatory.

The LBT has a light-collecting area equivalent to that of a single 39-ft-square surface and can produce images with a sharpness equivalent to that of a single 75-ft telescope. Its features include a panoramic 36-megapixel CCD camera in each of its mirrors.

Figure 2. This image shows a false-color rendition of the same galaxy and combines deep-red colors to highlight the smoother distribution of older, cooler stars.

The first images captured with both of LBT’s mirrors were taken in early January and were from the spiral galaxy NGC 2770. Figure 1 focuses on the clumpy regions of newly formed hot stars that are located in the galaxy’s arms. The other images highlight the distribution of older, cooler stars (Figure 2) and the structure of hot, moderate and cool stars (Figure 3). The NGC 2770 galaxy has a flat disc of stars and glowing gas and is slightly tipped toward Earth’s line of sight.

Figure 3. This image is a composite of ultraviolet, green and deep-red light and enhances the detailed structure of hot, moderate and cool stars in the galaxy.

It took the cooperation of more than 15 institutions to design, build and finance the LBT. Ownership and use of the device are split between research groups and universities. Arizona State University in Tempe, the University of Arizona in Tucson and Northern Arizona University in Flagstaff share a 25 percent stake. Istituto Nazionale di Astrofisica in Italy and the LBT Beteiligungsgesellschaft, a consortium of five institutes based in Germany, also each own 25 percent. The remaining 25 percent is split among several US universities.