EXPLORE


JOINRENEWJOIN

Get Your 2009 Year in Space Calendar!
  

Space Topics

Hubble Space Telescope


All telescopes on Earth's surface share a common limitation: the atmosphere absorbs infrared and ultraviolet wavelengths of light, and it blurs our vision at all wavelengths, which is what makes stars appear to twinkle. The Hubble Space Telescope was launched in April 1990 to be the first of NASA's Great Observatories to be located above Earth's atmosphere. Since its launch, Hubble's stunning images have yielded discovery after discovery in planetary science and astronomy, yielding clues to how planets, stars, galaxies, and even the whole universe formed and developed.

Hubble employs a wide variety of scientific imaging instruments to explore the farthest reaches of space. Instruments currently in use include the Advanced Camera for Surveys (ACS), which was used to discover Pluto's two new moons; the Wide Field and Planetary Camera (WFPC), a workhorse camera used to observe a wide variety of objects; the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), which has separated the light of extrasolar planets from their stars; the Space Telescope Imaging Spectrometer, which was the first instrument ever to detect an atmosphere around an extrasolar planet; and the Fine Guidance Sensors, which measure the motion of far-off stars as well as the orbital motions of Kuiper belt objects' tiny moons.

Despite Hubble's age, scientists are still eager to use it: there are requests for six to nine times as much observation time as is actually available on the telescope. However, four servicing missions performed by Space Shuttle astronauts have been necessary to keep it running, and without a fifth, the telescope will fall into the Earth's atmosphere some time after 2010.

Since its launch, Hubble has been joined in space by three more Great Observatories, the Compton Gamma Ray Observatory in 1991, the Chandra X-Ray Observatory in 1999, and the Spitzer Space Telescope in 2003. The James Webb Space Telescope, to be launched no sooner than 2013, is the planned replacement for Hubble.