NASA Christens the Spitzer Space Telescope

LMCBoy writes "NASA today renamed the Space Infrared Telescope Facility to the Spitzer Space Telescope, after a great scientist. The renaming coincides with the release of the beautiful first science images from the telescope, which was launched in August."

Comments

Re:Nice telescope, but bad name

[LMCBoy]

Magnification? Nobody cares about magnification.

Only angular resolution (a.k.a. "image clarity"), spectral coverage, and aperture size matter, really. Angular resolution is generally better from space because of the lack of atmospheric distortions (but with adaptive optics, ground telescopes are closing the gap). Spectral coverage is better in space, at least for those regions of the spectrum for which the atmosphere is not transparent (including big chunks of the IR spectrum, which Spitzer will address nicely). Aperture size is better from the ground, because it is so much cheaper to build big telescopes on Earth.

Re:Its a shame...

[LMCBoy]

FYI, space telescopes don't have onboard propellant. If you use propellant, pretty soon the telescope has an "atmosphere" of gas around it, and some of this will condense on the optics. This is Very Bad (tm). Instead, they manipulate internal gyros for attitude adjustment, but have no translational maneuvering ability. In fact, HST needs periodic visits from a space shuttle, in order to boost it back into a higher orbit (it's in such a low orbit, that it decays over the years due to slight atmospheric drag).

angular resolution clarification

[zwanglos]

To call angular resolution "image clarity" is greatly oversimplifying things. Angular resolution is a product of the size of the dish and the wavelength of the light observed. (Thus spectral coverage is not distinct from angular resolution). The atmosphere does pose a problem, but building the telescopes at higher elevations can greatly reduce distortion.

Extremely high angular resolution can be achieved on earth by linking up several telescopes. For instance, the VLBI technique created a telescope spanning 5,280 miles- with enough resolving power to, "sit in New York and be able to see the dimples on a golf ball in Los Angeles."

Space telescopes are great, but until it becomes cheaper to get large telescopes into orbit or on the moon nothing beats the basement bargain earth telescope.

Re:angular resolution clarification

[LMCBoy]

To call angular resolution "image clarity" is greatly oversimplifying things.

I wouldn't say greatly. Angular resolution is how well one can distinguish small angular sizes in the image. It is strongly related to the concept of image "sharpness" or "clarity".

The atmosphere does pose a problem, but building the telescopes at higher elevations can greatly reduce distortion.

Yeah, and with adaptive optics, you do even better, like I said.

Extremely high angular resolution can be achieved on earth by linking up several telescopes.

VLBI is great for radio telescopes, but even regular, non-VLB interferometry is very difficult in the infrared, and all but impossible (with current tech) in the optical.

Space telescopes are great, but until it becomes cheaper to get large telescopes into orbit or on the moon nothing beats the basement bargain earth telescope.

To quote one of my professors from grad school: "did you think about that?" Do you seriously believe that a "basement bargain earth telescope" cannot be outperformed by HST, SST, et al.?

Re:angular resolution clarification

[LMCBoy]

I'm talking about the fact that there are several ground-based observatories that consist of multiple telescopes (Keck, Magellan, VLT, LBT), and that one of the goals of this design is interferometry. None of these telescopes is currently planning on doing optical interferometry, because it's just too hard. They're all working on infrared interferometry, and even that is very difficult to accomplish. Especially with mirrors mounted independently, as all except the LBT are.