More great news. Congratulations to all who have worked on the project.
I understand the reasons for not putting a camera on or near the JWST, but I’m still a little sad that we’ll probably never get to see the thing in situ in all its operational glory.
Maybe one day when it finally expires, we can launch a “sample return” mission to tow it back.
One of the big numbers that been thrown around is that JWST has 344 single points of failure in its mission. Now that deployment has been completed, is there somewhere that lists how many of those points we have passed?
> Mike Menzel: 49 of the 344 single point failures remain and will remain throughout the mission. They are the same types of things on every mission, like propulsion. 15 are related to the instruments.
Not sure about the points of failure, but according to [1] only four deployment stages remain. So the large majority of point of failure should have been passed already.
Can anyone elaborate on these single points of failures? For example, are they actually single points of failure? Or is it a bit of exaggeration for marketing purposes (a bit of under promise, over deliver)?
What puzzles me is the maneuvering fuel. When that fuel runs out, the telescope can no longer orient itself. This ended the life of the Kepler telescope.
But aren't there other ways to orient in space?
1. use pressure from the solar wind
2. have 3 electric motors on 3 axis. Wouldn't spinning those motors rotate the craft? Electric power to do it would come from solar panels, giving it plenty of fuel.
For some context around what makes this deployment so remarkable, watch this[0] video that talks about the engineering/building aspects of the James Webb
[0] https://youtu.be/aICaAEXDJQQ
What I love about this project is that I had an active worry about its success, very few things in life inspire that kind of emotion. Well done to all involved, a true lifetime achievement. Can't wait for the images!
The benefit: “JWST’s instruments are designed to make discoveries across the spectrum of astronomy — ranging from the worlds and mini-worlds in our own solar system to alien planets circling distant stars, from the supermassive black hole at the center of our own Milky Way galaxy to the edge of the observable universe.” (https://www.geekwire.com/2021/high-cost-high-risk-high-hopes...)
Extremes on the cost/benefit helped create some extreme emotions, I agree!
Something I am wondering about the L2 orbit ... per NASA:
> Webb's orbit [~ around L2] ... is actually similar in size to the Moon's orbit around the Earth! This orbit (which takes Webb about 6 months to complete once) keeps the telescope out of the shadows of both the Earth and Moon. Unlike Hubble, which goes in and out of Earth shadow every 90 minutes, Webb will have an unimpeded view that will allow science operations 24/7.
Wouldn't remaining in Earth's shadow result in less interference, with Earth providing an extra sunshield? And "an unimpeded view" of what? I can't believe those cold, sensitive optics, with that carefully engineered sunshield, will point anywhere but away from the Sun.
If hubble is looking at sometihng not perpendicular to its orbit, during half the 90 minutes the target will be "behind" the earth, right? So it can only look at things that are to the left or right of its orbit.
The advantage of L2 is that the sun and earth will always be in the same direction (more or less) so it's easy to cancel it out. I don't think there's an orbit that would stay in Earth's shadow constantly that would have the same properties (without needing a ton of fuel)
Congratulations to the team, it's been a long road but it's satisfying to see so many folks efforts paying off.
I remember seeing a full size mock up of the JWST nearly ten years ago, and thinking it was just too big, complex and far out to succeed. But dedicated people made it happen.
> How long will it be breaking? (If at all, or of it is not already doing it).
All* of it's acceleration was given by the rocket at launch, it has been constantly "braking" since then as it's being pulled by earth's gravity, and it will reach L2 at same time it reaches a speed of 0.
* Not actually all in truth, since for margin of safety reason, the Ariane rocket purposefully imparted a lower than necessary speed, and the more precise thrusters on the JWST will be used to top it off with 3 different short burns (2 of which already happened), always staying just short of the required speed. The idea being that you want to make sure to be always missing a little bit of speed and readjust as needed, but never too much, as that is not recoverable, and the telescope would just drift away for ever.
Huge. This is the first large telescope observing in far infrared. Some things:
- very early galaxies (so far that they are redshifted to far IR). Hence the “looking into the start of the Universe” talk). We know they are there, and that they are unusual and super-interesting, but just can’t see them.
I think this is high on the agenda so I’m guessing some PR shots of ancient galaxies are due.
- cold objects nearby; brown dwarves, rogue planets etc. Maybe planets around nearby stars.
- I haven’t seen this discussed, but maybe: Kuiper Belt objects, maybe looking for Planet X etc.
The overall idea is that JWST can see very faint objects in the infrared spectrum. The analogy I've heard is that it could pick out a bedroom nightlight on the moon from earth.
Being able to see how galaxies evolved - you can see a galaxy 200M light years after the Big Bang and compare it to Hubble’s 500M years after the Big Bang.
Also spectra will be available to understand physical and chemical compositions at early times.
Word on corners of the interwebz has it that this is gonna prove the existence of aliens (or at least gov. are gonna frame JW as the indicator of alien life)
This feels perhaps like a silly comment, but I have this intuition that the data collected by JWST could prove to be some of the most important ever collected.
I keep telling people that, no matter what, we're going to learn something cool about the universe. I'm so excited to see these images. I mean, imagine humans 10,000 years ago, just surviving, maybe figuring out agriculture, and thinking about their place in the world. They looked up at the stars in wonder. Now, we've progressed to the point where we can polish gold down to the nanometer, and we're sending a giant hunk of origami circuits out to L2 to squint back to nearly the beginning of time as part of our eternal quest for answers.
People (including me!) really don't have a feel for just how far some of these instruments push things.
The Hubble Deep Field was a surprise to quite a few established astronomers. LIGO is measuring things way smaller than nucleons. The JWST can see so far back in time hat you can measure deltas from the beginning of the visible universe.
I know that I just don't have an appreciation for just how hard these things are to do.
Since 90% of the cost is probably in R+D of the telescope, one could build and deploy another for another 10%. Why isn't this done? Why is every space telescope completely unique?
How does this compare to the 'man on the moon' projects of China? It appears that from a purely scientific standpoint, this telescope will have a bigger impact than those of other space programs. Is my thinking on the right track here?
Also, is this complementary in function (and mission) to the Hubble? It appears to me that the spectrum is split up between Hubble and James Webb.
As an aside, it is interesting that the telescope is named in honor of a Lawyer turned administrator of NASA, James Webb (https://en.wikipedia.org/wiki/James_E._Webb). He must have been very capable indeed (or perhaps had the talent of attaching himself to very successful programs) because he was tapped by Kennedy to lead NASA at a time when the space race was at its peak. What's also weird is that James Webb worked as an administrator in all sorts of Government departments before being tapped to run NASA.
Programs like man on the moon make their contribution to mans knowledge through the engineering required to achieve the end, rather than in what they discover when they get there.
> Also, is this complementary in function (and mission) to the Hubble? It appears to me that the spectrum is split up between Hubble and James Webb.
Hubble's IR compliment was spitzer until it ran out of liquid helium. Webb is spitzer's replacement, with orders of magnitude more resolution.
Spitzer has qualified a lot of interesting mid IR targets to go look at in more detail.
In general non-vis space telescopes are more interesting than visible spectrum ones: Our vision only covers one octave so the odds that some random important physical process will best be observed in the visible spectrum isn't that great.
The visible spectrum is also the same spectrum that is well transmitted by the atmosphere so many vis observations can be conducted from earth with much larger and less costly instruments. Adaptive optics can mitigate atmospheric distortion at least somewhat, but there is no solution to non-transmission but space.
The atmospheric transmission has a two fold impact too: To study the atmosphere of extrasolar planets we need to study wavelengths that their atmospheres block. ... which, of course, are also wavelengths that our atmosphere blocks.
> How does this compare to the 'man on the moon' projects of China?
I don’t think space research has to be a zero sum game with one prescribed approach. The nature of research is that we need a multiple pronged approach into the unknown. If CNSA wants to pursue ‘Man on the Moon’ or JAXA wants to study asteroids, I see this as a win for humanity.
Alas no its too dark on the cold side and far too bright on the hot side, no camera can work in these extremes. Everything we know is based on telemetry and they set up a 3D model based on the telemetry so that we could see the live state.
I wonder if there are some aliens looking at this, and wondering if another advanced civilization has put this together (just like we were wondering with ʻOumuamua). To me James Webb looks definitely like alien technology, if it manages to pass 50 deployment stages, depending on 178 deployment mechanisms... The team working on this did an incredible job! https://www.youtube.com/watch?v=uUAvXYW5bmI&t=195s
> Some high priority scientific observations (GTO & GO) with the JWST are likely to be carried out during the commissioning period, since it is clearly desirable to begin to take science data as early as is technically feasible.
> Early Release Observations (EROs) will be taken by JWST during both the commissioning and post-commissioning phases of operation. These observations will be chosen to have wide public appeal and are designed to demonstrate the capabilities of the JWST instruments. Publication or reporting in any form of results of these observations is embargoed until the EROs are released.
[+] [-] jl6|4 years ago|reply
I understand the reasons for not putting a camera on or near the JWST, but I’m still a little sad that we’ll probably never get to see the thing in situ in all its operational glory.
Maybe one day when it finally expires, we can launch a “sample return” mission to tow it back.
[+] [-] dgrin91|4 years ago|reply
[+] [-] terramex|4 years ago|reply
https://twitter.com/SpcPlcyOnline/status/1479900221131964421
[+] [-] marcosdumay|4 years ago|reply
As always, it's useful to post this link:
https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html
[+] [-] FiberBundle|4 years ago|reply
[1] https://jwst.nasa.gov/content/webbLaunch/deploymentExplorer....
[+] [-] bmitc|4 years ago|reply
[+] [-] ducktective|4 years ago|reply
How can a system have more that one single point of failure?
[+] [-] albertopv|4 years ago|reply
[+] [-] jacquesm|4 years ago|reply
[+] [-] WalterBright|4 years ago|reply
But aren't there other ways to orient in space?
1. use pressure from the solar wind
2. have 3 electric motors on 3 axis. Wouldn't spinning those motors rotate the craft? Electric power to do it would come from solar panels, giving it plenty of fuel.
[+] [-] sam-2727|4 years ago|reply
[+] [-] dang|4 years ago|reply
[+] [-] 541|4 years ago|reply
[+] [-] mywacaday|4 years ago|reply
[+] [-] awb|4 years ago|reply
The benefit: “JWST’s instruments are designed to make discoveries across the spectrum of astronomy — ranging from the worlds and mini-worlds in our own solar system to alien planets circling distant stars, from the supermassive black hole at the center of our own Milky Way galaxy to the edge of the observable universe.” (https://www.geekwire.com/2021/high-cost-high-risk-high-hopes...)
Extremes on the cost/benefit helped create some extreme emotions, I agree!
[+] [-] dreamcompiler|4 years ago|reply
The most exciting idea is if that happens we'll realize they might have built their own version of JWST and proven we exist.
[+] [-] wolverine876|4 years ago|reply
> Webb's orbit [~ around L2] ... is actually similar in size to the Moon's orbit around the Earth! This orbit (which takes Webb about 6 months to complete once) keeps the telescope out of the shadows of both the Earth and Moon. Unlike Hubble, which goes in and out of Earth shadow every 90 minutes, Webb will have an unimpeded view that will allow science operations 24/7.
https://jwst.nasa.gov/content/about/orbit.html
Wouldn't remaining in Earth's shadow result in less interference, with Earth providing an extra sunshield? And "an unimpeded view" of what? I can't believe those cold, sensitive optics, with that carefully engineered sunshield, will point anywhere but away from the Sun.
[+] [-] ehsankia|4 years ago|reply
Maybe it needs the sun for its solar power?
> And "an unimpeded view" of what?
If hubble is looking at sometihng not perpendicular to its orbit, during half the 90 minutes the target will be "behind" the earth, right? So it can only look at things that are to the left or right of its orbit.
[+] [-] Rebelgecko|4 years ago|reply
[+] [-] jrockway|4 years ago|reply
[+] [-] Simon_O_Rourke|4 years ago|reply
I remember seeing a full size mock up of the JWST nearly ten years ago, and thinking it was just too big, complex and far out to succeed. But dedicated people made it happen.
[+] [-] ThinkBeat|4 years ago|reply
Right now, it is moving 0.3933km/s which according to Google is 1415.88km/h. That is pretty fast.
What speed does it need to be at for insertion and steady state? How long will it be breaking? (If at all, or of it is not already doing it).
[+] [-] baq|4 years ago|reply
[+] [-] sailingparrot|4 years ago|reply
All* of it's acceleration was given by the rocket at launch, it has been constantly "braking" since then as it's being pulled by earth's gravity, and it will reach L2 at same time it reaches a speed of 0.
* Not actually all in truth, since for margin of safety reason, the Ariane rocket purposefully imparted a lower than necessary speed, and the more precise thrusters on the JWST will be used to top it off with 3 different short burns (2 of which already happened), always staying just short of the required speed. The idea being that you want to make sure to be always missing a little bit of speed and readjust as needed, but never too much, as that is not recoverable, and the telescope would just drift away for ever.
[+] [-] asteroidbelt|4 years ago|reply
Shame.
[+] [-] elefanten|4 years ago|reply
[+] [-] rich_sasha|4 years ago|reply
- very early galaxies (so far that they are redshifted to far IR). Hence the “looking into the start of the Universe” talk). We know they are there, and that they are unusual and super-interesting, but just can’t see them.
I think this is high on the agenda so I’m guessing some PR shots of ancient galaxies are due.
- cold objects nearby; brown dwarves, rogue planets etc. Maybe planets around nearby stars.
- I haven’t seen this discussed, but maybe: Kuiper Belt objects, maybe looking for Planet X etc.
[+] [-] micromacrofoot|4 years ago|reply
https://jwst.nasa.gov/content/science/origins.html
Note that the next 5 months or so will consist of mirror cooling and calibration, so nothing until summer.
[+] [-] smoe|4 years ago|reply
https://www.stsci.edu/jwst/science-execution/approved-progra...
[+] [-] Iv|4 years ago|reply
[+] [-] mabbo|4 years ago|reply
The overall idea is that JWST can see very faint objects in the infrared spectrum. The analogy I've heard is that it could pick out a bedroom nightlight on the moon from earth.
[+] [-] binarymax|4 years ago|reply
Also spectra will be available to understand physical and chemical compositions at early times.
[+] [-] fotta|4 years ago|reply
[+] [-] jazzyjackson|4 years ago|reply
https://youtu.be/4P8fKd0IVOs
[+] [-] ducktective|4 years ago|reply
[+] [-] davesque|4 years ago|reply
[+] [-] gitgrump|4 years ago|reply
Your comment is not silly.
[+] [-] bsder|4 years ago|reply
The Hubble Deep Field was a surprise to quite a few established astronomers. LIGO is measuring things way smaller than nucleons. The JWST can see so far back in time hat you can measure deltas from the beginning of the visible universe.
I know that I just don't have an appreciation for just how hard these things are to do.
[+] [-] WalterBright|4 years ago|reply
[+] [-] rmk|4 years ago|reply
Also, is this complementary in function (and mission) to the Hubble? It appears to me that the spectrum is split up between Hubble and James Webb.
As an aside, it is interesting that the telescope is named in honor of a Lawyer turned administrator of NASA, James Webb (https://en.wikipedia.org/wiki/James_E._Webb). He must have been very capable indeed (or perhaps had the talent of attaching himself to very successful programs) because he was tapped by Kennedy to lead NASA at a time when the space race was at its peak. What's also weird is that James Webb worked as an administrator in all sorts of Government departments before being tapped to run NASA.
[+] [-] nullc|4 years ago|reply
> Also, is this complementary in function (and mission) to the Hubble? It appears to me that the spectrum is split up between Hubble and James Webb.
Hubble's IR compliment was spitzer until it ran out of liquid helium. Webb is spitzer's replacement, with orders of magnitude more resolution.
Spitzer has qualified a lot of interesting mid IR targets to go look at in more detail.
In general non-vis space telescopes are more interesting than visible spectrum ones: Our vision only covers one octave so the odds that some random important physical process will best be observed in the visible spectrum isn't that great.
The visible spectrum is also the same spectrum that is well transmitted by the atmosphere so many vis observations can be conducted from earth with much larger and less costly instruments. Adaptive optics can mitigate atmospheric distortion at least somewhat, but there is no solution to non-transmission but space.
The atmospheric transmission has a two fold impact too: To study the atmosphere of extrasolar planets we need to study wavelengths that their atmospheres block. ... which, of course, are also wavelengths that our atmosphere blocks.
[+] [-] FlyingSnake|4 years ago|reply
I don’t think space research has to be a zero sum game with one prescribed approach. The nature of research is that we need a multiple pronged approach into the unknown. If CNSA wants to pursue ‘Man on the Moon’ or JAXA wants to study asteroids, I see this as a win for humanity.
[+] [-] rwmj|4 years ago|reply
[+] [-] PaulKeeble|4 years ago|reply
[+] [-] asplake|4 years ago|reply
[+] [-] MichaelMoser123|4 years ago|reply
[+] [-] abadger9|4 years ago|reply
[+] [-] unknown|4 years ago|reply
[deleted]
[+] [-] jordanpg|4 years ago|reply
[+] [-] terramex|4 years ago|reply
> Early Release Observations (EROs) will be taken by JWST during both the commissioning and post-commissioning phases of operation. These observations will be chosen to have wide public appeal and are designed to demonstrate the capabilities of the JWST instruments. Publication or reporting in any form of results of these observations is embargoed until the EROs are released.
https://jwst-docs.stsci.edu/jwst-opportunities-and-policies/...
There is a chance for first images to be released before commissioning is complete, but no dates announced so far.