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How To Build a Telescope That Trumps Hubble
An anonymous reader writes "In cleanrooms around the country NASA and its contractors are building the James Webb Space Telescope, a marvel of engineering scheduled to launch in 2014. This gallery shows the features that will allow Webb to take the universe's baby pictures in infrared — most notably an 18-segment mirror and a 5-layer sunshield. I can't wait until Webb settles into its Lagrangian point way out beyond the moon and gets to work."
Why do you think it is infinite, without any proof whatsoever? All evidence we have is that the observable universe is finite, and observations of the early universe (thanks to the finite speed of light) match what the Big Bang Theory predicted. Ergo, it's the best answer we've got right now, and the burden of proof is on those who have evidence to the contrary to produce it.
Is it possible there's an unobservable universe outside of the observable universe? Of course. But you can't do science with it because it is simply impossible to observe.
I am officially gone from
Not that I'm expecting some catastrophic screw-up on the scale of the Hubble, but if there is a problem with the JWST, once it is sitting out at the Earth-sun L2, we won't be able to go visit it and repair it. I haven't heard of any contingency to allow it to come back to earth, so they've really got one shot to get it right.
I'm hoping everything is nominal.
I need trepanation like I need a hole in the head.
Of course not - the thing is a few billion Dollars to build and not exactly cheap to launch either.
In fact - if it does break, even if just in a minor way (e.g. the solar panels don't unfold because a space flea is jamming a gear), it's likely going to be a multi-billion dollar piece of space junk.
Why? Because it's going to sit at the Lagrange 2 point when it goes operational. That's far, far further than we've put humans (way beyond the Moon), which so far have been the only instruments adapt enough to do repairs on satellites (such as the ones for Hubble).
As it is, the James Webb Space Telescope is awesome - in infrared and -only- infrared. People suggesting it's a -replacement- for Hubble (IR, Visible, UV) are completely and utterly deluded.. or looking for additional grant money. They might as well claim it's a replacement for Chandra (X-Ray) as it's almost equally as idiotic.
Was space created by the Big Bang, or did the Big Bang happen inside of space that already existed?
Observe something that is more distant in space-time than the big bang, and settle the matter!
It is fine to speculate, but if you want coherent scientific models of the universe, you need to either assume the 13.7 billion light-year horizon or else show by observation or by theory that the horizon does not exist.
The ideas of an infinite theoretical universe aren't incompatible with a finite observable universe, but people who build telescopes are going to be concerned exclusively with the practical aspects of the latter, even if they believe in the former.
-fb Everything not expressly forbidden is now mandatory.
Actually, more than a dozen "Hubble space telescopes" were built and launched into orbit. The biggest differences are that they point at the Earth instead of away from it, and they are called KH-11 instead of HST. Oh, and their imagery data is mostly classified.
Science isn't something you can measure by how many buckets you collect. Not all buckets have the same value.
If you honestly believe that all Hubble and JWST are doing or will do is collect pretty pictures, you're either hopelessly ignorant or hopelessly biased. But ff you want to talk spectroscopy - consider that four of the Hubble five main instruments are dedicated to spectroscopy, and two of JWST's three main instruments are so dedicated. If you want to talk surveys... Check out Hubble's schedule from Feb 14, 2011, or January 29, 2011 for some recent survey campaigns that Hubble is participating in.