Astronauts to replace flawed Hubble camera
The emphasis will now switch from the engineering essential to keep the telescope working, to improving the astronomy it can perform.
The next stage of the repair mission, which should have started at about 4am (British time), is extremely delicate. In the third spacewalk, Story Musgrave and Jeff Hoffman have to replace the 270kg (595lbs) wide field and planetary camera.
The new camera contains a a coin-size mirror that has been ground to a prescription that should compensate for a flaw in Hubble's main 94in (238cm) mirror. In addition, the new camera will be able to 'see' well in ultra-violet light.
In theory, the camera should slide like a drawer into the telescope. But the astronauts will first have to remove the protective cover without touching the mirror itself. If, encumbered by space-suits and gloves, they do touch the mirror, they will ruin it: knocking it out of alignment and contaminating its surface.
In their spacewalk, which ended early yesterday morning, Endeavour astronauts Kathy Thornton and Tom Akers successfully equipped the Hubble telescope with two new solar panels to provide power for its operation. The astronauts spent more than six hours in space, fitting the new panels and jettisoning an old one that had buckled.
Nasa's mission controllers had ordered Ms Thornton and Mr Akers to ditch the panel, which was stuck in the open position, after Mr Musgrave and Mr Hoffman failed to roll it up and stow it in Endeavour's cargo bay during their first space walk on Sunday. Like the originals, the new panels have been supplied by the European Space Agency and built by British Aerospace.
Made of Teflon sheets covered with photovoltaic cells, the new solar arrays convert the sun's energy into electricity for scientific instruments inside the telescope. The original arrays fluttered like wings when the telescope moved in and out of darkness, interfering with the telescope's alignment.
As Ms Thornton let the panel go, shuttle commander Dick Covey slowly moved the craft away, leaving the panel to join some 7,000 pieces of debris from space missions, which will gradually be pulled towards the earth and burn up on re-entering its atmosphere.
As Ms Thornton released the panel, it caught the light from the sun, standing out against the deep blue of the Indian ocean 590km (360 miles) below as the craft orbited at 29,000km an hour.
David Cameron stung by jellyfish: PM hurt after ignoring advice of locals while on holiday
South Korea ferry: Vice principal rescued from sinking ship found hanged
Oscar Pistorius trial: The case against Oscar Pistorius – and why the prosecution claims his story doesn't add up
Peaches Geldof funeral: Private ceremony to be held at same place as her mother Paula Yates on Easter Monday
Shropshire criminals ‘using unmanned drones and infrared cameras to find illegal cannabis farms’ – and then steal from the growers
The food poverty scandal that shames Britain: Nearly 1m people rely on handouts to eat – and benefit reforms may be to blame
US Navy christens huge $3 billion destroyer ship USS Zumwalt that appears as a fishing boat on enemy radar
Scottish independence: It is the English who should be on their knees, begging the Scots to vote ‘No’
Nigel Farage fatigue? Half of voters ‘immune’ to Ukip’s appeal
Nigel Farage on Have I Got News For You: Ukip leader ridiculed over expenses and party 'fruitcakes'
Nigel Farage: I’m taking on the status quo, and the Establishment’s fighting back
- 1 Are you turning into your dad? The top ten signs you've embraced dad-ism revealed as survey says 38 is age men turn into their father
- 2 Overheard in Waitrose: documenting the chatter in 'Britain's poshest supermarket'
- 3 Video of British Muslims dancing to Pharrell Williams's hit Happy attacked as 'sinful'
- 4 24 people applied for the 'world's toughest job', here are their interviews
- 5 Grace Dent on TV: Game of Thrones has jumped the shark
£150.00 per week: QA Apprenticeships: This company is a company that specializ...
£153.75 per week: QA Apprenticeships: This company is an innovative outsourcin...
£150.00 per week: QA Apprenticeships: This company has been providing on site ...
£150.00 per week: QA Apprenticeships: We've been supplying best of breed peopl...