Hubble+Space+Telescope

How Does the Hubble Space Telescope Work? Every 97 minutes, Hubble completes a spin around Earth, moving at the speed of about five miles per second — fast enough to travel across the United States in about 10 minutes. As it travels, Hubble's mirror captures light and directs it into its several science instruments. (1) Hubble is a type of telescope known as a Cassegrain reflector. Light hits the telescope's main mirror, or primary mirror. It bounces off the primary mirror and encounters a secondary mirror. The secondary mirror focuses the light through a hole in the center of the primary mirror that leads to the telescope's science instruments. (1) People often mistakenly believe that a telescope's power lies in its ability to magnify objects. Telescopes actually work by collecting more light than the human eye can capture on its own. The larger a telescope's mirror, the more light it can collect, and the better its vision. Hubble's primary mirror is 94.5 inches (2.4 m) in diameter. This mirror is small compared with those of current ground-based telescopes, which can be 400 inches (1,000 cm) and up, but Hubble's location beyond the atmosphere gives it amazing clarity. (1) The Repair Crew On December 2, 1993, the Space Shuttle Endeavor carried a crew of seven into orbit for a mission that would involve five days of spacewalks and repairs on the Hubble. They performed a host of other tasks, replacing solar panels, fuse plugs, and other hardware. By December 9, they were finished. Hubble would be successfully serviced and repaired several times afterwards. Finally, in February 2002, astronauts added the advanced camera for surveys the first new instrument to be installed in Hubble since 1997. Each time astronauts performed a servicing mission, they also performed routine repair work, of fixing solar panels and thermal blankets, and upgrading equipment. (1) Changing Astronomy Hubble's discoveries have transformed the way scientists look at the universe. Its ability to show the universe in amazing detail has turned astronomical studies into certaintes. It has narrowed down the collection of theories about the universe even as it sparked new ones, showing the path for future astronomers. (1) Among its many discoveries, Hubble has revealed the age of the universe to be about 13 to 14 billion years, much more accurate than the old range of anywhere from 10 to 20 billion years. Hubble played a key role in the discovery of dark energy, a mysterious force that causes the expansion of the universe to go faster. (1) Hubble has shown scientists galaxies in all stages of evolution, including toddler galaxies that were around when the universe was still young, helping them understand how galaxies form. It found protoplanetary disks, clumps of gas and dust around young stars that likely function as birthing grounds for new planets. It discovered that gamma-ray bursts wich are strange, incredibly powerful explosions of energy they occur in very far away galaxies when massive stars collapse. And these are only a handful of its many contributions to astronomy. (1) The gigantic amount of astronomy based on Hubble's observations has also helped make it one of history's most important observatories. More than 6,000 scientific articles have been published based on Hubble data. (1) Some of the Pictures the Hubble Has Taken Works Cited 1. The Hubble: Hubble Essentials.NASA.6 March.2009. [] 2. Gallery: Picture Album.NASA.6 March.2009. []