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That's great news about the mirror, so stoked about this thing.
Perhaps someone who is better informed than me can explain something. When the telescope is orbiting L2, with the sunshield at its 'back' at all times, what parts of the sky will the mirror see? Can the mirror change orientation vis-a-vis the sunshield or is it fixed in position as per the images on the NASA website? If so then it will never be able to look along the earth-sun axis? Or earth-sun plane I suppose would be more accurate.
It will never face the Sus as the heat (black body radiation) will affect/ Interfere with the highly sensitive instruments.
There are even parts on the design to counteract the "push" from the sun's rays.
It's designed to look in areas of total dark and look for very distant and faint objects.
Think deep field view turned up to 11
If I'm wrong please correct me.
Understood it won't look towards the sun, but can it look directly away from it, in the earth sun plane? Or is it always pointing at L2, or always away from it? I'm not really clear on that.
It can see all of the 'sky', but not all at the same time, and it takes a year to get 100% coverage.
See this video from Scott Manley:
How NASA's $10 Billion Origami Telescope Will Unfold The Early Universe - YouTube
Edit: just watched the video and erased my mistake.
Wonders what (for giggles) it could see from L2 if it pointed back at earth. Guessing we pump out way to much IR For its sensitive instruments.
Wonders what (for giggles) it could see from L2 if it pointed back at earth. Guessing we pump out way to much IR For its sensitive instruments.
It would effectively be blinded by IR from the sun, which is why it’s oriented so that it’s always facing into deep space.
Well done everyone - Amy is on her way home to see her recently fostered little girl and I’m picking up the in-laws from the airport on Tuesday. Looking forward to hearing much more about events of the last couple of weeks on the drive back home. Unbelievable.
Amazing and unbelievable!!!
I don't have the vocabulary to do justice to this.
johndoh, your sense of pride shines through - as it should!
Imagine the scene in Amy's house in about 10 years time...hi mom/mum/mummy,what did you do in the 2020s?
Oh, nothing much...
Yay.
Has anyone come across a suitable video for a (very bright) 5 year old?
The Smarter Everyday ones are good but aimed at older kids who've done a bit of science at school already
There is a load of stuff on Webb Telescope Resources which may be suitable for you to help explain, but not direct reading/viewing for a 5 year old I would have thought.
johndoh, your sense of pride shines through
Absolutely - I have known my wife's brother since he was at Uni studying 'space' and he went off to LA to follow his dream. I remember going to the cinema with the family to see Apollo 13 and he was really excited as he got chatting to someone sat near us who happened to actually have been at Mission Control when it happened (we live in Harrogate so very close to the USA Menwith Hill station where this guy ended up working). He then met Amy at Northrop Grumman and they have both been working on the JWT project for the last 10 years. Now the long wait for the first images....
johndoh, your sense of pride shines through
+1. Thrilled for you all
This is pretty cool - someone has built an exceptional 1:7 model of the JWST...
https://stargazerslounge.com/topic/384283-jwst-model-scale-17/
My (almost) 4 year old son has been captivated by JWST, asking for updates each day on what has folded out.
I absolutely love how this kind of thing is multi-generational nerd-fuel.
When JWST is orbiting L2
i've got a stupid question...
there's nothing *at* L2, how can anything orbit around it?
various images/animations show the telescope orbiting an empty point in space, how does that work?!?
?
L2 is a ‘ring’ around the sun and the balance point is dependent on the position of the earth as it orbits the sun.
It’s a convenient place to park because it’s gravitationally stable / balanced and therefore uses minimal fuel to remain parked.
IGNORE - I lied. L2 is more complex than that. ^^^ is a description of L1 but the principles are probably broadly the same. https://solarsystem.nasa.gov/faq/88/what-are-lagrange-points/
Fantastic explanation of Lagrange points here:
Update on the telescope’s working life says it’s been effectively doubled, to twenty years, due to the pin-point accuracy of the launch. Incredible work by everyone involved in the project!
Fantastic explanation of Lagrange points here:
that is a great video, thanks for sharing.
still not sure i get it, but i suppose that's why we name these things after the clever sods who *do* understand them..!
it did feel very exciting to look at the moon yesterday, and realise that JWST is somewhere over *there*...
(i know it's further than the moon, but that's the right direction at least)
I find it interesting that Lagrange points are now being discussed on regular news programmes and in print, whereas previously about the only other form of literature where you’d find references was in science fiction stories!
Lagrange, or ‘libration’ points, as I believe they’re also called, are something I’ve been familiar with for years, as handy places to park installations or stations, because they’re naturally stable, and require relatively little fuel to keep whatever it is in place.
I’m really looking forward to seeing what JWST produces, although the images aren’t going to be what many people are expecting, compared to Hubble, which is mostly visible wavelengths, and not infrared.
Can you imagine the jostling and so on going on to try to get the first access to the ‘scope! 🤣
there’s nothing *at* L2, how can anything orbit around it?
That puzzled me too, but I found the answer. Look up 'halo orbit'
I’m really looking forward to seeing what JWST produces, although the images aren’t going to be what many people are expecting, compared to Hubble, which is mostly visible wavelengths, and not infrared.
I assume they will be able to re-interpret the infra-red images as broad colour spectrum images relatively easily?
Can it take selfies?
All motors and actuators on the mirror segments have been tested and are working. Now a 3 month job getting all the segments focussing together as one mirror.
Aligning the primary mirror segments to form one large mirror means each segment “is aligned to one-five-thousandth the thickness of a human hair”
:-O
I find it interesting that Lagrange points are now being discussed on regular news programmes and in print, whereas previously about the only other form of literature where you’d find references was in science fiction stories!
BBC had a Flat-Earther on yesterday (day before?) and justified it by some pathetic excuse around treating all views equally / impartiality etc.
Morons.
I assume they will be able to re-interpret the infra-red images as broad colour spectrum images relatively easily?
No different in principle from any other false colour reprocessing. In a sense when looking at very ancient galaxies that'll actually mean shifting the colour back into the visible range where it started out (having been redshifted to IR on the way here).
“Windows up, grab those sunnies, and don’t let the seagulls steal ya chips!”
Webb got parked.
https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html
first "calibration" image recieved
Interesting read. Just made me wonder how long it takes to transfer 54gb of data over such a long distance? And how do they do it?
Can it take selfies?
Yes!!
This “selfie” was created using a specialized pupil imaging lens inside of the NIRCam instrument that was designed to take images of the primary mirror segments instead of images of space. This configuration is not used during scientific operations and is used strictly for engineering and alignment purposes. In this case, the bright segment was pointed at a bright star, while the others aren’t currently in the same alignment. This image gave an early indication of the primary mirror alignment to the instrument. Credit: NASA
^ isn't that just smile inducing? Amazing science...
Still looks like a cross between Blockbusters* and Paradroid*
*oldies only relevance ;D
can I have a P please Bob
Watched a video on the first images, am I right it took a selfie?
Watched a video on the first images, am I right it took a selfie?
Yep. Look about 5 posts up ^ for a bit more info
D'oh!
🤦 just spotted that
D'oh!
🤦 just spotted that
Interesting read. Just made me wonder how long it takes to transfer 54gb of data over such a long distance? And how do they do it?
Bandwidth Vs latency.
It'll take 5 seconds for a signal to reach earth.
But in terms of the rate you can transmit the data that doesn't degrade like it does down copper wire or fibre.
Seems it's got an 8mbit connection(theoretical 28mbit) according to that, so about 1mb a second download.
5 seconds for the signal to travel 1.5 million Km’s is mind blowing. At 270gb per day they can transfer data from that distance at not to dissimilar speeds to what we (my company) transfer between two UK datacentres. (We could transfer it faster, but cost constraints mean we don’t)
Pretty interesting stuff. We’re transferring about 380gb of data per day.