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Here's the main reasoning for placing it at L2: http://jwst.nasa.gov/orbit.html
Right I understand the reason. But as my question says, I don't understand how a rocket inserts it into that orbit.
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Right I understand the reason. But as my question says, I don't understand how a rocket inserts it into that orbit.
This video shows the steps that take it from a folded-up thing stuffed into a rocket to a deployed telescope at L2: https://www.youtube.com/watch?v=bTxLAGchWnA The rocket is out of the picture fairly early on in the timeline.
STScI will be the Science and Operation Center for JWST.
Hey, my job's on HN! I work on JWST (simulation software, among other stuff) and I think it's pretty cool too :)
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Interesting tidbit: JWST can't see blue. While Hubble could see entire visible light spectrum, astronomically infrared is more interesting. So JWST can see infrared, but not blue. Astronomical images always have been heavily edited and it never was "what you may see", but it is more so for JWST.
It's not just that IR is "more interesting" (maybe it is), but it's much more difficult to see through the atmosphere. It's obviously cheaper and easier to build huge optical telescopes on the ground, but to see into the infrared, you need to get above the atmosphere. Edit: source http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ir_tutor...
Regarding our atmosphere filtering IR: do you feel the heat of the sun when it shines on you? That's light. Infrared.
Edit: Additional point of fact: our atmosphere interferes with light by scattering it away from its angle of incidence. Light with a longer wavelength is able to get through without scattering (IR, red, orange, yellow, etc) light with a shorter wavelength (blue) is more likely to collide with a molecule of something on the way in, and it gets bounced around so frantically that all those blue light waves seem to kind of pile up and come from everywhere. No, our atmosphere's light transmission woes are much more deleterious to the smaller wavelengths of light than to IR.
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Interesting tidbit: JWST can't see blue. While Hubble could see entire visible light spectrum, astronomically infrared is more interesting. So JWST can see infrared, but not blue. Astronomical images always have been heavily edited and it never was "what you may see", but it is more so for JWST.
It's not just that IR is "more interesting" (maybe it is), but it's much more difficult to see through the atmosphere. It's obviously cheaper and easier to build huge optical telescopes on the ground, but to see into the infrared, you need to get above the atmosphere. Edit: source http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ir_tutor...
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It's not just that IR is "more interesting" (maybe it is), but it's much more difficult to see through the atmosphere. It's obviously cheaper and easier to build huge optical telescopes on the ground, but to see into the infrared, you need to get above the atmosphere. Edit: source http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ir_tutor...
IR is profoundly more interesting, precisely because it is able to penetrate all sorts of media, most especially interstellar dust and gasses, allowing JWST (and others) to see stars that can't be seen by their visible light. Regarding our atmosphere filtering IR: do you feel the heat of the sun when it shines on you? That's light. Infrared. Edit: Additional point of fact: our atmosphere interferes with light by scat…
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Until this post I didn't realize it wasn't going to orbit Earth in roughly the same spot as Hubble -- it's going to be roughly 4 times further away from Earth than the Moon is, orbiting L2! http://jwst.nasa.gov/orbit.html
I never understood how we can launch something into an L2 orbit. Does the rocket just fly out there and stop? Just it get caught at that location?
Basically, the rocket doesn't just fire in a straight line away from the Earth all the way into orbit. It starts arcing very soon into the ascent, and the thrust is nearly parallel to the Earth's surface for much of the journey.