Construction of dummy structures for $1.8 billion James Webb Space Telescope begins
Northrop Grumman's design for NASA's James Webb Space Telescope (JWST), successor to the Hubble space telescope, has been approved and dummy structures are now being built for thermal testing. Costing $1.8 billion, and scheduled for launch in 2011, the 6,200kg (13,640lb) telescope will operate for five to 10 years using a 6.5m (21ft)-diameter mirror, 2.5 times larger than Hubble's.
At a meeting in Paris at the end of March, the project's 10-country consortium gave the green light to the construction of dummy structures. Made of the same material as the actual components for the telescope, these structures will be subjected to the temperatures the telescope will experience in its 1.5 million km (940,000 miles) orbit, at the L2 Lagrange point beyond the Moon.
"Everyone is confident we've got a good design. We decided to start building hardware," says EADS Astrium's John Thatcher, consortium project manager for one of the telescope's instruments. "Denmark is to make the dummy carbonfibre support struts, for example. A dummy may look like an instrument from the outside but have no actual moving parts."
The JWST instrumentation includes three cameras that are sensitive to infrared wavelengths. The most sophisticated of these is the mid-infrared instrument. This is being developed by an international team led by the University of Arizona and the UK's Astronomy Technology Centre in Edinburgh.
The Webb telescope is a collaboration between NASA and the European and Canadian space agencies. Germany is providing the mechanism for moving the mirrors, Spain is producing instrumentation and France is constructing one of the imagers.
ROB COPPINGER / LONDON
Source: Flight International
