Hubble marks two decades of changing science
By Till Mundzeck, dpa
May 16, 2010, 2:30 pm TWN
Washington -- There is hardly any other scientific instrument in the world that can match the Hubble telescope in fame. In the four centuries since the invention of the first telescope, Hubble and its sister telescopes in space have revolutionized the way we understand the cosmos.
Hubble has been orbiting the Earth for 20 years this month. "It has achieved much more than anyone thought possible," says Robert Fosbury, the head of the European Space Agency's team that coordinates with NASA on the Hubble telescope. "Hubble has given us access to completely new areas of astronomy."
That growth in knowledge is illustrated by the work done by Hubble on the distant worlds known as extrasolar planets. "When Hubble launched no-one had discovered an extrasolar planet," says Fosbury. Today, Hubble is even examining the chemical make-up of the atmospheres of those planets. Thanks to Hubble astronomers were able to prove the existence of organic molecules outside our solar system and in this way the telescope is on the trail of possible extraterrestrial life.
Hubble's big advantage is that it is stationed outside the earth's atmosphere and has a clear view of space. With Hubble astronomers were able to identify individual stars in distant galaxies for the first time. Orbiting telescopes are also able to see wavelengths of light, such as infrared, which are absorbed by the atmosphere.
Hubble has created a huge body of work in its lifetime. It has taken approximately 600,000 images of about 30,000 objects in space since 1990. Every month it sends 80 gigabytes of information back to earth — the equivalent of about 80 large encyclopedias. The cost of the project to NASA and the European Space Agency, which has a 15 percent stake in Hubble, has been US$10 billion.
The telescope has also helped to explain how stars and planets are created, set the age of universe at approximately 13.7 billion years and has investigated the mysterious concept of dark energy, which is driving the universe's expansion.
It has also delivered countless images that have enthralled the public. Hubble's success is also the story of well coordinated publicity. "These images are often just as significant for the scientists as for the public," says Fosbury. The type of image can help the scientists maintain an overall view. The brilliant colors the images come in are a combination of several individual exposures in different wavelengths.