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NASA Unveils Hubble's Successor
dalutong writes "BBC News has an article detailing NASA's replacement for the much-loved Hubble telescope. The $4.5 billion telescope will be placed in orbit 1.5 million km from Earth and will be almost three times the size of the Hubble. It is set to launch in 2013. They also plan to service the Hubble in 2008."
Its going to be nearly a million miles away, so its out of reach for any repair mission (for the forseable future anyway.)
JWST will provide diffraction-limited images at 2 micron. It will have imaging and spectrographic capabilities in the near and mid-IR -- everything from 6000AA out to 27micron with the mid-IR imager and spectrograph (MIRI). StSci has a JWST primer online here (pdf link).
..."JWST is named after James E Webb, Nasa Administrator during the Apollo lunar exploration era; he served from 1961 to 1968."
To add more evidence. Look, wikipedia!
http://en.wikipedia.org/wiki/James_Edwin_Webb
To 1-up wikipedia. Look, NASA!
http://www.jwst.nasa.gov/whois.html
The man whose name NASA has chosen to bestow upon the successor to the Hubble Space Telescope is most commonly linked to the Apollo moon program, not to science. Yet, many believe that James E. Webb, who ran the fledgling space agency from February 1961 to October 1968, did more for science than perhaps any other government official and that it is only fitting that the Next Generation Space Telescope would be named after him.
Complete bullshit.
Your cost estimates are accurate, but the rest of your argument is total shit. Adaptive optics, WHEN it works (which is rarely, and with difficulty), can approach the angular resolution of HST in a VERY SMALL field of view. You cannot get 0.05 arcsec, diffraction limited images over a wide field of view, that is possible with HST.
"Designing a mirror to withstand a launch vehicle" is a problem that has been solved. And the only two current, viable telescope proposals for telescopes larger than 10m are the Thirty Metre Telescope (TMT) and the Giant Magellan Telescope (GMT). OWL is not a concept that is being taken very seriously...ESO certainly hasn't put its money where its mouth is.
Your final point, about not many lines in that part of the spectrum, belies a complete lack of understanding of what you are talking about. The UV (accessible with STIS, and the Cosmic Origins Spectrograph, which will fly on SM4 in late '08) are so full of lines that they overlap all over the place. See, for example, Morton (2003), ApJS, 149, 205, for a comprehensive list. At low redshift, lines of HI, OI, OVI, CIV, NV, CII, SiII, SII, FeII, NI...all are in the UV, in the STIS band. Furthermore, space is the ONLY place these wavelengths can be observed, because of the atmosphere is opaque to wavelengths shorter than about 3300 angstroms.
The imaging will be near infrared with particular capability near 2 microns, but the 5 micron capability is alos of interest. There is also a smaller camera working from 5 to 27 microns. This is mid-infrared. The resolution of this instrument will not be so good because of the longer wavelength. The Keck Telescope can get better image quality. But what it will have is spectroscopic capability and much greater sensitivity. We've gotten quite alot of milage out of the much smaller Spitzer Space Telescope using it's 5--30 micron spectrograph. This new instrument should really open things up, allowing us to analyse stars in galaxies as they were when the universe was 12 billion years younger. All telescopes can be considered time machines, but this one is made to see some of the very first stars. You can read more about it here: http://www.stsci.edu/jwst/instruments/.s -selling-solar.html
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Rent solar power: http://mdsolar.blogspot.com/2007/01/slashdot-user
Also wrong. Try this one.
It is not exactly obstacles that cause the redshift, but rather the expansion of the universe. Dust can redden light, but this is really just subtracting blue light. Gravitational lensing is acromatic. In the gamma-rays, Compton scattering can shift photons to lower energy, but it does not preserve spectral features the way that the cosmological redshift does.
I recall that the Orion program which is currently under development will have the capability to do the job. It is slated to replace the shuttle and also have the ability to reach the moon. One of the goals was to be able to do a service mission of the JWT far far away. More info here. http://www.nasa.gov/mission_pages/constellation/ma in/index.html/
Geometry.
Earth only has 12000km diameter. Sun has 1.4 million km diameter.
For earth to give shade, it would have to be closer than AU*(r_earth/r_sun), which is much closer than the lagrange point.
Simply put: you would get a dark spot on the sun, but no complete cover.
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
Ground based telescopes are good only for light that is not filtered by the atmosphere. There is a whole lot of spectrum outside it. The JWST targets the infra-red wavelengths, which would be much harder to do with an atmosphere above it
http://www.dieblinkenlights.com