Slashdot Mirror
James Webb Space Telescope Cost Overruns Adding Up
digitaldc writes "The scale of the delay and cost overrun blighting NASA's James Webb Space Telescope (JWST) has been laid bare by a panel called in to review the project. The group believes the final budget for Hubble's successor is likely to climb to at least $6.5bn, for a launch that is possible in September 2015. But even this assessment is optimistic (PDF), say the panel members. Estimates for JWST's total cost to build, launch and operate have steadily increased over the years from $3.5bn to $5bn. Along with the cost growth, the schedule has also eroded. The most recent projected launch of 2014 has looked under pressure for some time. Charles Bolden has ordered a reorganization of the project and has changed the management at its top. Whereas Hubble sees the Universe mostly in visible light, JWST will observe the cosmos at longer wavelengths, in the infrared. It will see deeper into space and further back in time, to the very first population of stars."
Smaller satellites implies smaller mirrors. The resolving power of a telescope depends on the diameter of its mirror. So you could have many small telescopes in orbit and only get fuzzy, unclear images, or one big one that delivers sharp images, and due to the mirror size is more sensitive to boot.
As for land-based, build a 100 meter mirror and scope and you will see.... nothing in infrared, which is what the JWST is designed for. The earth's atmosphere absorbs and re-radiates low infrared which means all you can really see is a sort of dull glow. Yes you can see stars, but the really faint light you want is drowned out by atmospheric emissions. That's why the JWST has to be kept so cold, because thermal emissions from the mirror would drown out any light signal from truly faint objects.