A space telescope is a special equipment developed for the purpose of observing distant planets, galaxies, and other outer space objects, from outer space.
The Hubble which is orbiting the Earth outside the atmosphere is subject neither to electromagnetic radiation or light pollution from artificial light sources on the Earth.
The idea for the space telescope arose in 1923, when German scientist Hermann Oberth, one of the founders of rocketry, suggested blasting a telescope into space aboard a rocket.
In 1946, Lyman Spitzer Jr., an American astrophysicist, wrote a paper proposing a space observatory. He would spend the next 50 years working to make the space telescope a reality.
ESA agreed to provide funding and supply one of the first generation instruments for the telescope, as well as the solar cells that would power it, and staff to work on the telescope in the United States, in return for European astronomers being guaranteed at least 15% of the observing time on the telescope. In 1983 the telescope was named after Edwin Hubble, who made one of the greatest scientific breakthroughs of the 20th century when he discovered that the universe is expanding.
The construction of the Hubble Space Telescope took eight years and about 1.5 billion dollars. It was completed in 1985.
The mirrors where the firs of many challenges to be faced by the team because the Space telescope was to be used for observations from the visible through the ultraviolet (shorter wavelengths) and was specified to be diffraction limited to take full advantage of the space environment. Therefore its mirror needed to be polished to an accuracy of 10 nanometers.
The spacecraft in which the telescope and instruments were to be housed was another major engineering challenge. It would have to adequately withstand frequent passages from direct sunlight into the darkness of Earth's shadow, which would generate major changes in temperature, while being stable enough to allow extremely accurate pointing of the telescope. A shroud of multi-layer insulation keeps the temperature within the telescope stable, and surrounds a light aluminum shell in which the telescope and instruments sit.
Wide Field Camera 3 can be used to study objects everywhere from the far-distant universe to our own solar system's backyard. It helps examine the way galaxies evolve over time, the history of individual galaxies, and the mystery of "dark energy," the strange force that seems to be accelerating the expansion of the universe.
These instrument was upgraded 2 times over the course of the Hubble's life.
The Cosmic Origins Spectrograph, which breaks ultraviolet radiation into components that can be studied in detail, is used to examine galaxy evolution.
The Advanced Camera for Surveys conducts surveys of the universe and studies the nature and distribution of galaxies.
The Near Infrared Camera and Multi-Object Spectrometer is Hubble's heat sensor. Its sensitivity to infrared light makes it useful for observing objects obscured by interstellar gas and dust
The Space Telescope Imaging Spectrograph is a versatile instrument that acts somewhat like a prism, separating light from the cosmos into primary colors.
The Fine Guidance Sensors are targeting devices that lock onto "guide stars" and measure their positions relative to the object being viewed.
Servicing Mission 1: December 1993 Servicing Mission 2: February 1997 Servicing Mission 3A: December 1999 Servicing Mission 3B: February 2002 Servicing Mission 4: May 2009
According to NASA, "One of Hubble's key duties was to help astronomers determine a precise age for the universe. The telescope helped astronomers accomplish that goal, narrowing the universe's age to 13 to 14 billion years old, an accuracy of about 10 percent
The Hubble Space Telescope captured this image of a gamma ray explosion
Black scars reveal the aftermath of Jupiter's impact with nearly two dozen chunks from comet Shoemaker-Levy 9 in 1994.
A collection of Hubble Space Telescope images shows distant supernovas, the death explosions of massive stars.
In conclusion the Hubble space telescope has been a major help in the discovery of the secrets of the universe. It is unfortunate that it will out of commission by 2014 but we will have it’s legacy.