The Hubble Space Telescope Essay Example for Free

The Hubble Space Telescope Essay The Hubble Space Telescope is a telescope placed in orbit over our planet’s atmosphere. This particular positioning (outside the earth’s atmosphere) allows the set of device to take sharp optical images of otherwise very faint spatial objects. The telescope was named after Edwin Hubble, the person who is responsible for discovering galaxies outside the milky way. In relation to the intended function of the Hubble Space Telescope, Edwin Hubble is also the one who created Hubble’s law, the calculated measurement of the rate at which the universe is expanding (Burows, 1991). The Hubble Space Telescope was launched in 1990 and has become one of the most important instruments in the history of astronomy. The data retrieved from the telescope has been responsible for ground breaking theories and help answering questions in astrophysics. In this paper, we will describe the Hubble Space Telescope and all its roles in the development of our science of astronomy. II. Engineering of the Telescope The design of the telescope consists of several parts: Optical Telescope Assembly The most important part of the Hubble Space Telescope design is the mirror and optical system. Because they are designed for different functions, there are significant differences of the Hubble Space Telescope design compare to general telescope. A general telescope is designed to observe objects illuminated with visible light, thus, the mirror of the telescope needed only to be polished to and accuracy of one-tenth of the wave length of that visible light (Spitzer, 1979). However, the Hubble Space Telescope was designed to capture object illuminated by lights ranging from ultraviolet to near-infrared. Thus, the mirror of the telescope needed to be polished to an accuracy of 1/20 of the wavelength of visible light (Burrows, 1991). It was realized that the polishing job would require extreme precision and the assistance of sophisticated tools and gadget. Thus, the polishing was performed by Perkin-Elmer, using computer-controlled polishing machines. In pursue of accuracy, Perkin-Elmer spend more than a year to complete the polishing stage. In 1981, the mirror was completed with the addition of a reflective aluminum coating 75nm thick and a magnesium protective fluoride coating 25nm thick. The additional coating was installed to increase mirror’s reflectivity in ultraviolet light (Burrows, 1991). II. 2. Ground Support The role of the ground support system of the Hubble Space Telescope was performed by the Space Telescope Science Institute (STScI). The institute was established in 1983, located in Baltimore, in the Homewood campus of Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA). Operations of the Hubble Space Telescope are monitored 24 hours a day by the Hubble Flight Operations Team which consist of four teams of flight controllers. The ground support has the responsibility to manage the scientific operation of the telescope and oversee the delivery of data products to astronomers. The engineering support required for the operations is provided with NASA at the Goddard Space Flight Center in Greenbelt, Maryland (STScI, 2003). The ground support team has had some incident relating to the delay of Hubble’s launch schedule. The launch was delayed for four years to account for the Challenger disaster. The mirrors and other instruments were to be kept in clean rooms until the rescheduled launch. In 1990 however, when the launch was finally performed, the dust that has accumulated on the mirror required nitrogen dusting and the system needed to be tested extensively again to ensure safety (STScI, 2003). II. 3. Spacecraft System The designers of the project stated that the spacecraft that carried the Hubble out to space was considered a big engineering challenge. First and foremost, it must have the capability of enduring the major changes in temperature, as the craft would pass through direct sunlight as well as dark areas of Earth’s shadow. The spacecraft must also be stable enough to allow extremely accurate pointing of the telescope. Finally, a shroud of multi-layered insulation was installed to keep telescope’s temperature stable including a light aluminum shell. To address the stability issue, a graphite-epoxy frame was installed within the aluminum shell to keep Hubble and its parts aligned and in tact.