Last week NASA gave the green light to a final mission to the Hubble Space Telescope by a space shuttle in 2008 to service, repair and upgrade the venerable 16-year-old orbiting observatory ? a visit that should extend the Hubble?s life to at least 2013. Already, the Hubble has been credited as having a greater impact on astronomy than any instrument since the telescope Galileo used to discover the moons of Jupiter. Here are some details of its remarkable record:
Launch date April 24, 1990
Cost at launch $1.5 billion Spacecraft operations Goddard Space Flight Center, Greenbelt
Science operations Space Telescope Science Institute, Baltimore
Galactic origins: Hubble?s sharp vision has revealed small, irregularly shaped galaxies at the farthest reaches of time and space. Their stars and gases provide clues to how the first structures to form after the Big Bang coalesced into the large galaxies we see nearby today.
Expansion of the universe: Hubble?s views of a stellar explosion 10 billion years ago showed that the expansion of the universe slowed after the Big Bang. An earlier discovery revealed that that expansion later began accelerating, hinting at a mysterious ?dark force? that emerged to push the galaxies apart.
Age of the universe: By measuring the distances to distant galaxies and ?white dwarf? stars in our own galaxy, two teams of Hubble astronomers arrived independently at new estimates of the age of the universe: 12 to 14 billion years. Before Hubble, estimates ranged from 10 billion to 20 billion years.
Black holes: For decades only theoretical, black holes have become a confirmed reality since Hubble?s launch. Astronomers have peered through the crowd of stars, dust and gas at the core of active galaxies and measured the influence of these dense concentrations of matter as their immense gravity swallows everything that blunders within range ? even light itself.
Exoplanets: Long the province of science fiction writers, the question of whether planets circle stars other than our sun was answered by Hubble. Its images revealed dusty disks ? planetary nurseries ? swirling around many nearby stars, including at least half of those in the Orion Nebula (below). In 2001 Hubble was first to directly detect and analyze the gases in an exoplanet?s atmosphere.
Size: 43.5 feet long, 14 feet wide ? the size of a truck trailer
Weight: 24,500 pounds
Primary mirror width: 7.8 feet
Altitude: 351 miles
Earth orbit: once every 97 minutes
Speed: 17,500 mph
Power consumption: 2,800 watts of solar power, equal to 28 household lightbulbs
Science data output: 120 gigabytes a week, enough to fill 3,600 feet of books on a shelf.
Pointing accuracy: equivalent to holding a laser beam steady on a dime, 200 miles away.
Published science: About 5,950 papers in peer-reviewed journals, a number NASA says is ?unprecedented? for one scientific facility. And it now grows by 650 each year.