In 1977 the U.S. Congress voted to fund construction of the Hubble Space Telescope, and it was completed in 1985. It is named for the astronomer Edwin Hubble who was the first scientist to recognize the overall expansion of the Universe, and to relate the red-shift in the light from distant objects to their distance from us. The telescope was deployed on April 25th 1990. Once it started operation, the mirror was found to have a tiny flaw that had a huge impact on the image quality.
Thus, in 1993, NASA sent a mission to instal a corrective mechanism, called COSTAR (the Corrective Optics Space Telescope Axial eplacement), which was a complete success. They also installed a new Wide Field Planetary Camera, along with several new components.
Another Mission, launched on February 11, 1997, installed a wide range of new instruments to extend the telescopes range into the near infrared, thus increasing substantially the range of the telescope. Following this very successful mission, NASA decided to extend the planned operational window of the telescope from 2005 to 2010.
On November 13, 1999, the fourth of six on-board gyroscopes failed, so the telescope went into safe mode as it was unable to work without a minimum of three. Along with replacement gyroscopes and a new computer, a number of other enhancements were installed in December of 1999.
March 2002 saw the fourth maintenance mission to instal the Advanced Camera for Surveys (ACS). This comprises a set of three cameras each having specialized capabilities. Overall, they have ten times the power of the camera they replaced, and cover wavelengths from the visible spectrum out to the far ultraviolet. Some of the aims of the new cameras are to photograph the inner regions of galaxies, search neighboring stars for planets and proto-planets, to study weather on planets in our solar system, and to study distant galaxies in much more detail.
The most recent, and almost certainly the last, maintenance mission was in May 2009. This saw the installation of two new scientific instruments: the Cosmic Origins Spectrograph (COS) and the Wide Field Camera 3 (WFC3). Two existing instruments were repaired along with the installation of new batteries, gyroscopes and computer. The success of the mission prompted NASA to extend operations to 2014.
With the completion recently of what is probably the last Hubble upgrade, I though it appropriate to have a page dedicated to its' history, its' achievements and some of the beautiful images it has produced. In addition to taking amazing photographs, observations have contributed enormously to our knowledge of the cosmos; for example, determining the rate at which the Universe expands, and contributing to the finding that the rate of expansion of the Universe is increasing, the so-called accelerating Universe, rather than decreasing as previously believed. Its observations have helped to fix more accurately the probable age of the Universe as well as its constituents in terms of matter, dark matter and dark energy.
The resolution of the telescope is equivalent to reading the date on a small coin from 1.6 km (1 mile) away.
Note that mages in this section are courtesy: NASA, ESA, Hubble unless stated otherwise.
Galaxy M100 before and after COSTAR implementation
Astronomy & Cosmology
Hubble Space Telescope