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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."
Put a bad toupee on a telescope.
The budget cuts announced by Obama include cutting $64 million from the James Webb Telescope program, "which an indendent group of experts "found to have a fundamentally broken estimate of cost and schedule".
While I recognize the U.S. is totally fucked, economically, this is a mistake. Throwing a minor budget item with huge potential like this under the bus in the name of pretending to become fiscally responsible is beyond short-sighted.
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
As a professional astronomer I hoped this thing would never have happened. It costs 6 billion and at this price tag a 5% overrun is $300 million, about six times the cost of the entire SDSS project, which has undoubtedly gave us more science that James Webb ever will. True, Hubble and JWST make great pictures, function as amazing PR machines, but most science at the end of the day comes from survey imaging and spectroscopic observations.
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.
http://en.wikipedia.org/wiki/KH-11_Kennan
You really don't know much do you? The radiation comes from the beginning of the universe, back when everything was a huge soup of particles. It's one of the greater proofs for the big bang theory, since there's no other reason for it to be there than to have one point where the universe was so dense it was irradiating in a nearly uniform manner. By studying the irregularities in the emissions, we can then learn more about that state in the universe's evolution, as well as what happened after that.
There's no distance to speak of because when those were around, they were everywhere and the universe wasn't of the same dimensions. We can measure that the universe is expanding, the big bang theory says there was a time where it was essentially a singularity, thus we can say (with good probability of being right) that the universe is finite.
Is it finite in the sense of a sheet of paper? Probably not. There won't be a wall with "the Universe ends here." written on it. Rather, it might very well be like the flat Earth theories: a loop that uses an additional dimension to complete. Whereas the Earth is a 3D object that was being represented as 2D (so you'd have edges even though they do not actually exist), it's very possible the universe loops around in another higher dimension.
OK, I have no productive contribution here, but the phrases "Hubble trumping" and "trouble humping" are now echoing through my head.