The Hubble Decade

The Hubble Decade

December 1999, and NASA has scrambled a space shuttle for an emergency mission. It's a crack crew, on a flight that's been brought forward six months. Short of a human catastrophe in space, there's only one satellite that can command this sort of attention - the Hubble Space Telescope.

Launched almost 10 years ago, Hubble is the jewel in NASA's crown. While planetary missions fail, and endless arguments dog the International Space Station, Hubble has been consistently turning up trumps, with stunning images of deep space and new insights into the birth and evolution of the Universe.

When Sky & Telescope magazine recently polled readers for the cosmic images of the century, two came in miles ahead of the rest of the pack: the Apollo astronauts' first view of the Earth from the Moon - and the Hubble Space Telescope's glorious image of the great dark pillars in the Eagle Nebula.

View from the top

On the scientific front, Hubble's achievements are also out-of-this-world. It’s an international mission - a collaboration between NASA and the European Space Agency - and literally thousands of astronomers from all over the world have used Hubble’s eagle eye to dissect over 13,000 objects in the cosmos. The data sent back to Earth would fill over ten thousand CD-Roms.

Hubble’s role in astronomy demonstrates the maxim that bigger isn’t necessarily better, even where telescopes are concerned. Astronomers have a choice of some 30 ground-based telescopes that are larger than Hubble. The space telescope's unique advantage is its crystal-clear vision. While other telescopes must look upward through the Earth's churning atmosphere, Hubble has an undistorted view of the cosmos.

In theory, that is. Soon after Hubble's launch, astronomers found that Hubble's images were blurry - due to a fault in shaping its main mirror, which threw out its intended curve by about 1/50 the diameter of a human hair. In December 1993, visiting astronauts installed 'contact lenses' - in reality, small curved mirrors - which corrected the fault. And since then, Hubble hasn't looked back.

Jupiter’s ‘black eyes’, after it was assaulted by Comet Shoemaker-Levy-9

Photo - NASA

Science from space

The space telescope has looked at every type of object in the Universe, from the nearest - the Moon - to the most distant galaxies ever seen. It wasn't really designed to investigate planets, but even in the Solar System Hubble has turned up trumps. When the Mars Pathfinder mission was on its way to the Red Planet, NASA controllers used Hubble to monitor dust storms on the target world. The space telescope also observed a massive storm on Saturn, and showed - for the first time - Pluto's moon Charon clearly separate from Pluto itself. Most important, Hubble had a prime view of Comet Shoemaker-Levy-9's smash into Jupiter in 1994. The telescope saw both the giant fireballs as the comet fragments impacted the planet, and the vast 'black eyes' left on Jupiter's clouds afterwards.