Author Topic: James Webb Space Telescope  (Read 71805 times)

Offline bknight

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Re: James Webb Space Telescope
« Reply #180 on: January 24, 2022, 05:44:06 PM »
JWST is now in its L2 orbit, and getting ready to start work.

James Webb telescope parked in observing position
Quote
Thirty days after it was launched, the James Webb telescope has arrived at the position in space where it will observe the Universe.

The Lagrange Point 2, as it's known, is a million miles (1.5 million km) from Earth on its nightside.

Webb was finally nudged into an orbit around this location thanks to a short, five-minute thruster burn.

Controllers back on Earth will now spend the coming months tuning the telescope to get it ready for science.

Key tasks include switching on the observatory's four instruments, and also focusing its mirrors - in particular, its 6.5m-wide segmented primary reflector.

There's still a lot of adjustment and checking to do, but it won't be too long before we start to see some amazing images.
Looking better with each milestone passed.
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Offline raven

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Re: James Webb Space Telescope
« Reply #181 on: January 24, 2022, 11:41:54 PM »
The mirrors, antenna and sun shade all have deployed successfully. I wouldn't say we're home free, but this is looking more and more hopeful all the time.

Offline bknight

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Re: James Webb Space Telescope
« Reply #182 on: February 11, 2022, 04:39:06 PM »
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
Eugene Cernan

Offline Peter B

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Re: James Webb Space Telescope
« Reply #183 on: June 08, 2022, 05:19:46 AM »
And now JWST appears in a game:

https://roman.gsfc.nasa.gov/game.html

(Which is actually about the Nancy Grace Roman Space Telescope.)

My top score so far is 577...

ETA: 667...
« Last Edit: June 08, 2022, 05:22:14 AM by Peter B »

Offline Jeff Raven

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Re: James Webb Space Telescope
« Reply #184 on: July 13, 2022, 07:30:12 PM »
I definitely lack any expertise or training in a relevant area to critique or evaluate the images released yesterday, but they seem amazing, and I can only imagine just how much new information the raw data is going to provide.  Showing the contrast between JWST's and Hubble's images of the same areas of the sky was very smart on their part.  The average person has no idea what a lot of the technical specs and jargon mean, but when they see things side by side, it makes it much clearer. (no pun intended)

Offline molesworth

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Re: James Webb Space Telescope
« Reply #185 on: July 20, 2022, 07:15:20 AM »
Looks like one of the meteoroid impacts has done some serious damage to a mirror segment :

https://www.livescience.com/james-webb-space-telescope-micrometeoroid-picture
https://www.space.com/james-webb-space-telescope-micrometeoroid-damage

From the reports it sounds like it'll only have a minor effect on the quality of the images and other data, but the worry is that there seems to have been quite a few hits since deployment, and there's no way to predict the likely frequency of further impacts. Fingers crossed this one was a one-in-a-billion unlucky early hit.
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Offline Count Zero

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Re: James Webb Space Telescope
« Reply #186 on: July 21, 2022, 02:27:28 AM »
Who could have guessed that an abnormal amount of space debris would collect (instead of drifting away and scattering) at the place we selected because objects orbiting there tend to stay there?

Larry Niven predicted this in his 1967 short story "Flatlander".  Beowulf Schaeffer describes an early deep space ship passing through a Lagrange point and taking "unexpected" micrometeor damage.
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Offline Grashtel

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Re: James Webb Space Telescope
« Reply #187 on: July 21, 2022, 11:25:00 PM »
Who could have guessed that an abnormal amount of space debris would collect (instead of drifting away and scattering) at the place we selected because objects orbiting there tend to stay there?

Larry Niven predicted this in his 1967 short story "Flatlander".  Beowulf Schaeffer describes an early deep space ship passing through a Lagrange point and taking "unexpected" micrometeor damage.
The Webb is at L2, its not one of the stable points, anything there will drift away from it without active stabilisation, its useful as its stable relative to Earth and a lot further away than a normal orbit would be stable at
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Offline cjameshuff

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Re: James Webb Space Telescope
« Reply #188 on: July 22, 2022, 09:37:26 PM »
Who could have guessed that an abnormal amount of space debris would collect (instead of drifting away and scattering) at the place we selected because objects orbiting there tend to stay there?

Larry Niven predicted this in his 1967 short story "Flatlander".  Beowulf Schaeffer describes an early deep space ship passing through a Lagrange point and taking "unexpected" micrometeor damage.
The Webb is at L2, its not one of the stable points, anything there will drift away from it without active stabilisation, its useful as its stable relative to Earth and a lot further away than a normal orbit would be stable at

Right, it's L4 and L5 that tend to collect things, objects tend to just pass through L1, L2, and L3...their importance is that there are low-energy trajectories to and through them. JWST's lifetime is set by propellant required to maintain its orbit, it will wander off into solar orbit when that is exhausted. There may be an elevated amount of debris passing through that area of space, but it's not really clear how elevated, or what the velocity and size distributions are. Another reason it might have been a good idea to send some lower-cost precursor missions...