Hubble's 15 years in space
2005-04-26 10:43
Washington - The Hubble Space Telescope turned 15 on Monday, with 750 000 photographs of deep space and earth to its credit, but its future is now uncertain.
Hubble was launched by the Space Shuttle Discovery on April 25, 1990, and opened a new era in astronomy.
However, the telescope, a co-operative effort of Nasa and the European Space Agency, would not be operational until three years later.
A mirror that had been improperly ground was corrected in 1993, when a new camera was also installed in the first repair mission by a space shuttle.
Once repaired, the telescope beamed back photographs 10 times sharper than ever before of galaxies, supernovas, giant explosions marking the death of a star and the birth of a black hole.
Galaxy of achievements
Thanks to Hubble, flying above the atmospheric distortion that hinders even more powerful earth-based telescopes, scientists have been able to confirm that the universe is rapidly expanding and to calculate precisely its age, at 13.7 billion years, according to Nasa.
Among other achievements, Hubble's observations allowed scientists to confirm the existence of a strange form of energy called dark energy; proved the existence of super-massive black holes; provided sharp views of a comet hitting Jupiter; and showed that the process of forming planetary systems is common throughout the galaxy, Nasa said.
Nasa has so far decided not to send a shuttle to repair the ageing Hubble, citing the $450m it would cost to do so. But the space agency's new chief, Michael Griffin, has said he would revisit the decision.
Astronauts have serviced Hubble four times, and many scientists hoped that a fifth service mission would be funded to enable Hubble to function to 2011, when its infrared replacement, the James Webb Space Telescope, is scheduled to arrive.
Currently, it is believed that Hubble's ageing solar cells will provide enough energy to survive to 2007.