Astronomers are battling to save the most powerful telescope ever to be sent into space, amid fears it is about to be axed by Congress. NASA’s $13billion James Webb Space Telescope – the replacement for its remarkably successful Hubble observatory – will see further than ever to the edge of the universe.

But chief scientist Dr Heidi Hammel is campaigning for professional and amateur astronomers to write to politicians to stop it getting cancelled as the US government seeks to cut billions of dollars in public spending.

The JWST’s main mirror will be 6.5 meters (21.3ft) in diameter, compared to Hubble’s 2.5 meters, allowing it to collect more than five and a half times as much light. That will allow the scope to view the first galaxies ever to form and to peer in the infrared through clouds of dust to see newly born planetary systems. Another role would be to follow up on planet discoveries by Kepler and to build on the work of NASA’s Spitzer observatory.

But with costs soaring and the US space agency cutting international missions already spending over its budget, NASA administrator Charles Bolden has already admitted earlier this month that the launch date is likely to slip from 2015 to 2018 at the earliest.

It has led to some space-science wags renaming the JWST the Just Wait Space Telescope. But the fear of astronomers is that, after is has consumed all NASA’s money, the project will be cancelled altogether.

They believe it will be an easy target as Congress seeks to make $38 billion cuts in spending following the political compromise that averted a government shutdown earlier this month.

Dr Hammel, a co-director at the Space Science Institute in Boulder, Colorado, which oversees Hubble and JWST research, called on astronomers to write to NASA and their Congress member to save the new telescope. Speaking at the Northest Astronomy Fair in New York this month, she said less than one day’s war spend could get the project back on track.

The JWST, a joint project between NASA, and the European and Canadian space agencies, is a highly ambitious mission. Its mirror plus a tennis-court sized sunshade are too big to fit on its launch rocket fully open.

It means that they will have to unfold to millimeter accuracy once an Ariane 5 rocket has carried the telescope into space, a hugely technically demanding operation. And unlike Hubble which is in Earth orbit, the JWST will sit a million miles from Earth at a so-called Lagrangian point in the Earth’s orbit around the Sun but where it will be too far to send a service mission to reach it if anything goes wrong.

Last November, an official NASA review said the JWST was already at least $1.5billion over budget and called for another £500million to be found in 2011 and 2012 to keep the telescope on schedule for a September 2015 launch.

But the agency is already strapped for cash and has cancelled some high-profile plans for Mars and other planetary missions, having already decided against a manned return to the Moon.

Some professional astronomers controversially believe NASA could have saved cash it lost in sending four shuttle missions to service the $15billion Hubble space telescope which is marking its 21st year of operation. Each shuttle launch costs $1.5 billion.

One professor at a leading UK observatory told Skymania: “It was a mistake to carry out the Hubble repair missions. Earth-based telescopes are today able to perform as well as Hubble thanks to techniques like adaptive optics. The money spent sending the shuttle to carry out repairs could have helped pay for the James Webb Space Telescope.”

Our thanks to Nick Howes who attended NEAF 2011 in New York and tipped us off about this interesting, if worrying, story.

Update, July 6, 2011: The House of Representatives’ Appropriations Committee which handles the science budget has proposed a $2 billion cut in spending for NASA and specifically proposed axing the JWST, saying it is is “billions of dollars over budget and plagued by poor management.”

©PAUL SUTHERLAND, Skymania.com

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