Famous Telescopes and Observatories in the U.S.
Space and Astrology 9/16/11
By: Yona Williams
Telescopes and observatories in the United States are found in states, such as California, Texas, Wisconsin, and Hawaii. In this article, you will learn about the following: Hobby-Eberly Telescope, Keck I and II Telescopes, and Yerkes Observatory.
Hobby-Eberly Telescope Ã¢â‚¬â€œ Texas
The Hobby-Eberly Telescope in Texas was designed to collect light for spectrum analysis rather than for visually exploring the sky. Located at the McDonald Observatory, the telescope has been in operation since 1999 and possesses an overall diameter of 360 inches Ã¢â‚¬â€œ making it one of the largest optical telescopes in the world. The telescope is named after the former Texas Lieutenant-Governor Bill Hobby and for Robert E. Eberly, benefactor from Penn State.
The telescope blends a handful of features that separates it from the majority of telescope designs. Because of these features, it costs less to build this piece of equipment. For starters, the telescope mirror does not move to track the night sky, but instead, instruments at the focus are moved across the face of the standstill mirror. This allows the tracking of a single target for up to two hours. The primary mirror is comprised 91 hexagonal elements. It is less expensive to use this type of mirror than a single large primary. While the main mirror itself is fixed at 55 degrees angle, the telescope can rotate around its base. The secondary can move Ã¢â‚¬â€œ providing access to around 70 to 81% of the sky at its location.
Keck I and II Telescopes Ã¢â‚¬â€œ Hawaii
The Mauna Kea Observatory in Hawaii is home to the Keck I and II Telescopes, which were open in 1992 and 1996. Positioned 13,600 feet on top of a mountain, they were situated above 40 percent of the Earth's atmosphere. The two telescopes are seen as the most powerful instruments on the ground in the world. With the help of up to 36 hexagonal mirrors, the total aperture reached is 400 inches. Together, the two telescopes work together to create a single astronomical interferometer.
Yerkes Observatory Ã¢â‚¬â€œ Wisconsin
In Williams Bay, Wisconsin, the Yerkes Observatory serves as one of the largest refracting instruments in the world. Completed in 1897, the telescope uses a 40-inch mirror and is operated by the University of Chicago. The history connected to the observatory has helped gain a reputation for being the 'birthplace of modern astrophysics.' The observatory was founded by George Ellery Hale and financed by Charles T. Yerkes. At the time, observatories were solely used to house telescopes and accommodate observers, but the Yerkes Observatory was different. It represented a more modern concept of integrating laboratory space for physics and chemistry along with the observation equipment.
Yerkes Observatory offered the largest refracting telescope that successfully aided the study of astronomy. There is also a collection of more than 100,000 photographic plates on the premises Ã¢â‚¬â€œ some which date back to the 1890's. The most recent research conducted at the observatory included work on the formation of globular clusters, infrared astronomy, and objects located close to Earth.