Troubled mission that proved to be out of this world
The moment of truth had arrived.
The world's media and astronomers filed into a room, to see the first fruits of decades of work and hundreds of million pounds worth of investment, as the first images of the Hubble space telescope were about to beamed onto a screen.
“Some eyebrows went up,” recalled David Leckrone, who had been working on Hubble for 14 years.
“It was supposed to be a picture of a binary star, a pair of stars. But it was just sort of a fuzzy blur.”
One member of the audience tried to put a brave face on the situtation: “It’s OK, isn’t it? That’s how it’s supposed to look?” But those who knew about these things just stared in silence. This was not how it was supposed to look.
It is 30 years today since the US space shuttle Discovery launched from Cape Canaveral in Florida, with the Hubble telescope on board. An international collaboration between Nasa and the European Space Agency, it had been billed as the most significant development in astronomy since Galileo built his first telescope some 400 years ago. But at this meeting in Nasa's Goddard Space Flight Centre in Maryland, it looked like the venture had been a dreadful, and very expensive mistake.
But from that very shaky start, the world's first space telescope – named after Edwin Hubble, an American astronomer who discovered in the 1920s that the universe was expanding, has come to redefine our understanding of the universe we inhabit. And remarkably, three decades on, the telescope is still fully operational, some 15 years after its expected sell-by date.
Sophie Allan, head of teaching at the National Space Station in Leicester, says Hubble has been a remarkable achievement.
"It's been a phenomenal success, it's reshaped our understanding of the universe, and showed us things we would never have imagined," she says. "It's a real testament to the engineering standards of Hubble that something constructed in the 80s is still providing us with this knowledge."
The idea of the space telescope was first mooted in 1923, by three physicists, the German Hermann Oberth, American Robert H Goddard, and Russian Konstantin Tsiolkovsky. A further paper, in 1946, by US astronomer Lyman Spitzer, further made the case for a space-based observatory, arguing that its images would not be affected by the turbulence in the atmosphere, which caused stars to twinkle. A space-based telescope, he added, would be able to observe infrared and ultraviolet light, which were strongly absorbed by the atmosphere when viewed through land-based telescopes. But while Spitzer may have successfully argued the case for putting a telescope into space, it would be a while before the idea became a reality.
In 1968, Nasa developed firm plans for a space-based reflecting telescope, with a launch planned for 1979. However, the vast cost of the project meant funding was hard to come by, leading to collaboration with the European Space Agency. The ESA agreed to provide vital equipment and funding in exchange for being allowed at least 15 per cent of the observation time.
The team was ready for launch by 1986, but the project was delayed once more by a terrible tragedy. In January that year the space shuttle Challenger disintegrated over the Atlantic Ocean, killing its crew of seven, leading to the whole shuttle fleet being grounded for the next three years. Without the shuttle, there was no way of blasting Hubble into space, so it would be another four years before the dream was realised.
Hubble, about the size of a single decker bus, was finally blasted into space on April 24, 1990. It was a tremendous feat for science and engineering, but it was a tiny detail which set the telescope off to a shaky start. The blurry pictures, which sent shockwaves around the scientific community, were the result of Hubble's 8ft mirror being flatter than it should have been by just one-fiftieth of the width of a human hair.
This was not the telescope's first teething trouble. The British-made solar panels, which powered the six separate instruments, had already malfunctioned, with Nasa scientist Stephen Maran saying: "Deploying the solar panels is technically more challenging than the launch of a shuttle one more time."
But that was nothing compared to the problem with the faulty mirror, which was not rectified until a service team visited the helicopter in space in 1993.
Leckrone recalls the first pictures from the telescope after the repairs.
“When the first image came down, it was extraordinarily beautiful,” he says. “From that point on, every place we pointed Hubble in the sky, there was something new and remarkable. It’s a terrific comeback story.”
Paul Millington, of the National Space Centre, says the influence that Hubble has had on our understanding of the universe has been massive.
"Hubble has reinvigorated and reshaped our perception of the cosmos and uncovered a universe of unexpected wonders," he says.
"Hubble has revealed properties of space and time that for most of human history were only probed in the imaginations of scientists and philosophers. Today, Hubble continues to provide views of cosmic wonders never before seen and is at the forefront of many new discoveries."
He says that thanks, in part, to Hubble we now know the universe is 13.7 billion years old.
"The telescope has helped scientists determine the process of how planets are born," he adds. "We now know that nearly all galaxies may harbour supermassive black holes."
He adds that Hubble detected the first organic molecule discovered on a planet outside our solar system, as well as a distant supernova that suggests the universe only recently began speeding up.
This knowledge has not come cheap, though. Initially expected to cost 400 million US dollars, this was soon adjusted upwards to 1.5 billion dollars. By the time of its launch, the cost was said to have escalated to 4.7 billion, and in 2010 it was estimated that with maintenance costs, Hubble had cost 10 billion over the first 20 years of its life.
There was a time when it looked like Hubble would not see its 20th birthday, let alone its 30th. The 2003 Columbia space shuttle disaster led to the cancellation of its 2005 service mission, which would have extended Hubble's life by another five years. However, a public outcry led to the decision being reversed, and in 2009 Hubble received what would be its final service.
The retirement of the US space shuttle fleet means that Hubble no further maintenance will be able to be carried out on Hubble, and the fact that the telescope is still operating some 11 years since its last visit is remarkable in itself
Sophie Allan says Hubble will probably continue to operate until the mid 2020s, by which time its successor, the James Webb Telescope, will be in operation.
She says the new telescope, the size of a tennis court, is so big that no spacecraft would be able to carry it in its operational state.
"It's going to be launched folded up, and will open up in space," she says. "The mirror will be made up of interlocking hexagons."
Unlike Hubble, James Webb will use infra-red imagery, which will enable it to delve even further into the history of the universe.
"The thing to remember about telescopes is that they area also time machines," she says, explaining that because the speed of light is constant, looking at great distances is effectively looking back through time at light that was visible in the past.
"At the moment, Hubble takes us back to 13.46 million light years ago, that's almost back to the Big Bang, but James Webb may take us even further back than that."
And if all this sounds a bit out of this world, Sophie points out that Hubble has had a profound impact on the technology most of us use during our everyday lives.
"The camera technology that's used in mobile phones was a direct development from Hubble," she says.
Five facts about the Hubble telescope:
Hubble Space Telescope is about the size of a bus, and weighs 24,500lbs pounds, about the weight of two elephants.
Hubble gathers energy from the sun using two 25ft solar panels. It requires much less power than one might think, averaging 2,100 watts of power usage, compared to 1,800 watts for a hairdryer.
Hubble orbits the Earth at a cruising speed of 17,000 miles per hour, and takes 15 minutes to rotate 90 degrees.
Hubble has observed locations more than 13.4 billion light years away, meaning it has seen light that existed in the universe 13.4 billion years ago.
Astronomers using Hubble data have published more than 13,000 journal articles, making it one of the most productive scientific instruments ever built.