Is anyone else following the James Webb telescope progress?
https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html
https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.html
.7 MILES per second...
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Loved this post!!!!The most bizarre thing to me about the position is that it will be in a Lagrange point L2 where gravity is in equilibrium and it will stay there. There are other Lagrange points near the Earth, with some other satellites in L1 and some asteroids in a couple of the others. Mind blowing stuff.
I have been hearing about this for years now. I completely stopped watching the news quite a while ago and next thing I know somebody told me it launched the other day, successfully too. Oh happy days. Can't wait to get some data back and watch some documentaries on the findings. Very exciting.
For sure, but at least it's up there. At least now if there's problems, like Hubble, it might be possible to fix. A failed launch means complete failure and destruction of this amazing tool.Launch seemed to the least worrisome part. There’s something like 350 failure points during the sequence to unfold the whole thing that will happen over the next 28 days or so. It’s gonna be really intense to watch.
HST was an easy fix in LEO space. This is ~6x the distance to the moon. Webb will not be accessible to "go up and fix". Even Elon's magic Starship won't be able to get there to do that. Everything has to work, and as much as I have read, there are contingency plans to get the most out of this if something does go wrong. Odds are, nothing will. One can't spend two decades considering and accommodating all the possible failure modes and billions of dollars and not do the most to make sure it works.For sure, but at least it's up there. At least now if there's problems, like Hubble, it might be possible to fix. A failed launch means complete failure and destruction of this amazing tool.
The most bizarre thing to me about the position is that it will be in a Lagrange point L2 where gravity is in equilibrium and it will stay there. There are other Lagrange points near the Earth, with some other satellites in L1 and some asteroids in a couple of the others. Mind blowing stuff.
[fair warning... lots and lots of words below. TLDR version, hell yeah I'm following... have been for years!!!]
HST was an easy fix in LEO space. This is ~6x the distance to the moon. Webb will not be accessible to "go up and fix". Even Elon's magic Starship won't be able to get there to do that. Everything has to work, and as much as I have read, there are contingency plans to get the most out of this if something does go wrong. Odds are, nothing will. One can't spend two decades considering and accommodating all the possible failure modes and billions of dollars and not do the most to make sure it works.
The Next Generation Space Telescope* (sorry... James Webb Space Telescope or "JWST" to his friends) is sort of my jam. I've had the great fortune to be vaguely affiliated with two space telescope projects in my career up to this point. First, Kepler ( https://en.wikipedia.org/wiki/Kepler_space_telescope ) and more recently the companion follow-up mission, TESS ( https://en.wikipedia.org/wiki/Transiting_Exoplanet_Survey_Satellite ). I was heavily involved in the pre-observations that were essential for target selection for Kepler once the mission was de-scoped somewhat to accommodate the reduced data down-link capacity when the antenna was modified from a steerable one to a fixed configuration. That work transitioned to the initial follow-up and characterization of candidate targets post-discovery before additional time was expended on larger and more sensitive (more expensive) telescopes. That transitioned quite seamlessly to very similar work for TESS, whose mission profile and survey area was built around a place in the sky where Webb will be able to always observe.**
I have no direct involvement with Webb, but knowing what it will be able to do will further the understanding of the exoplanets we characterize with TESS... that is pretty damn exciting. I might have no say in what it specifically looks at, but knowing the observations I make are instrumental in guiding where Webb will look is pretty damn cool, no matter how you look at it. It's just one link in a very long chain.
Fingers, arms, legs, eyes, toes... whatever I can cross I have crossed hoping everything deploys correctly. I saw a talk a few years ago about Webb that detailed (with an absolutely horrifying animation) all of the deployment operations over the next 30-plus days post-launch. There are so many things that have to go right, but I also have a great deal of confidence in "people smarter than I am" who have looked at this a million times that it will.
The science that will come from Webb will improve our understanding of the universe in which we live, and I can't wait to see what it is able to produce.
* I've never been a fan of the name, and not for the recent "woke" reasons most people were up in arms over the name. My issue is it was named after a f'n administrator and ultimately politician and not a scientist. It was also named years before construction was even close to being finished. I love the tradition of the Japanese who wait until whatever spacecraft they have launched is in orbit before naming it. The man signed paychecks and work orders and and made sure the early steps of the Apollo project didn't go off the rails and nothing significantly more. Yet, what will likely be as scientifically significant (if not more) as the Hubble Space Telescope not being named after a scientist seems like a seriously weak punt with no imagination or even a vague consideration of the scientific relevance of such a machine. As a result, it will always be "the Next-Generation Space Telescope" or NGST in my mind.
** Because of NGST's orbit at L2, and where the Earth-Sun-Moon will appear in the sky for it, there are two places it the sky in the north and south called "continuous viewing zones" or CVZ's where none of those three objects will ever get close to. This geometry will allow un-interrupted views where observations won't have to stop as those relatively bright targets get too close or pass through the field of view. The TESS mission intentionally selected where it would observe around these same CVZ's to maximize the number of candidate targets found in those spots so the highest fidelity targets from the mission would be found in places in the sky where NGST would more easily be able to observe for extended periods of time.
The Five Lagrange points in a "two-body" system are really interesting. https://en.wikipedia.org/wiki/Lagrange_point They are places in space where the gravitational pull between two objects is balanced and basically zero. Think of being at the pivot point in a see-saw or teeter-totter. L4 and L5 are gravitational wells... think of the bottom of valley where something on the slope of the hill wants to roll to the bottom, but once there is stable and doesn't want to "roll out" of the valley. The other three, including L2 are "high points"... like the top of a mountain. When there, it's stable, but does require a little help to make sure it stays there. There are thrusters on NGST that will be able to give periodic nudges to make sure it stays there, but as a natural "balance point" these will be relatively small and infrequent. L2 is a stable and "quiet" location in space that is close enough to Earth that communication is relatively easy for the volume of data that will be downlinked, but far enough from the Earth-moon system that they won't interfere with or introduce unwanted background signal to the instruments.
Finally, and a little but of a brag, but one of the instruments on NGST was designed, built and will be "operated" from the University of Arizona. I know one of the people who was involved in the precision micro-soldering on the instrument. The whole "six degrees of separation" here is remarkably cool. Knowing someone who helped build a part of this is remarkable. I'd be beside myself if I were him knowing something I helped build was in space, will remain in space pretty much forever, and will be instrumental in astronomy for well over a decade would be beyond humbling. I can't wait to talk to him in a few weeks and see what he thinks about the last few days!
Im nodding lol. I realized after I said go up and fix it that it was pretty dumb, but I wasn't gonna change it. I knew you'd find you way here. Exciting stuff![fair warning... lots and lots of words below. TLDR version, hell yeah I'm following... have been for years!!!]
HST was an easy fix in LEO space. This is ~6x the distance to the moon. Webb will not be accessible to "go up and fix". Even Elon's magic Starship won't be able to get there to do that. Everything has to work, and as much as I have read, there are contingency plans to get the most out of this if something does go wrong. Odds are, nothing will. One can't spend two decades considering and accommodating all the possible failure modes and billions of dollars and not do the most to make sure it works.
The Next Generation Space Telescope* (sorry... James Webb Space Telescope or "JWST" to his friends) is sort of my jam. I've had the great fortune to be vaguely affiliated with two space telescope projects in my career up to this point. First, Kepler ( https://en.wikipedia.org/wiki/Kepler_space_telescope ) and more recently the companion follow-up mission, TESS ( https://en.wikipedia.org/wiki/Transiting_Exoplanet_Survey_Satellite ). I was heavily involved in the pre-observations that were essential for target selection for Kepler once the mission was de-scoped somewhat to accommodate the reduced data down-link capacity when the antenna was modified from a steerable one to a fixed configuration. That work transitioned to the initial follow-up and characterization of candidate targets post-discovery before additional time was expended on larger and more sensitive (more expensive) telescopes. That transitioned quite seamlessly to very similar work for TESS, whose mission profile and survey area was built around a place in the sky where Webb will be able to always observe.**
I have no direct involvement with Webb, but knowing what it will be able to do will further the understanding of the exoplanets we characterize with TESS... that is pretty damn exciting. I might have no say in what it specifically looks at, but knowing the observations I make are instrumental in guiding where Webb will look is pretty damn cool, no matter how you look at it. It's just one link in a very long chain.
Fingers, arms, legs, eyes, toes... whatever I can cross I have crossed hoping everything deploys correctly. I saw a talk a few years ago about Webb that detailed (with an absolutely horrifying animation) all of the deployment operations over the next 30-plus days post-launch. There are so many things that have to go right, but I also have a great deal of confidence in "people smarter than I am" who have looked at this a million times that it will.
The science that will come from Webb will improve our understanding of the universe in which we live, and I can't wait to see what it is able to produce.
* I've never been a fan of the name, and not for the recent "woke" reasons most people were up in arms over the name. My issue is it was named after a f'n administrator and ultimately politician and not a scientist. It was also named years before construction was even close to being finished. I love the tradition of the Japanese who wait until whatever spacecraft they have launched is in orbit before naming it. The man signed paychecks and work orders and and made sure the early steps of the Apollo project didn't go off the rails and nothing significantly more. Yet, what will likely be as scientifically significant (if not more) as the Hubble Space Telescope not being named after a scientist seems like a seriously weak punt with no imagination or even a vague consideration of the scientific relevance of such a machine. As a result, it will always be "the Next-Generation Space Telescope" or NGST in my mind.
** Because of NGST's orbit at L2, and where the Earth-Sun-Moon will appear in the sky for it, there are two places it the sky in the north and south called "continuous viewing zones" or CVZ's where none of those three objects will ever get close to. This geometry will allow un-interrupted views where observations won't have to stop as those relatively bright targets get too close or pass through the field of view. The TESS mission intentionally selected where it would observe around these same CVZ's to maximize the number of candidate targets found in those spots so the highest fidelity targets from the mission would be found in places in the sky where NGST would more easily be able to observe for extended periods of time.
The Five Lagrange points in a "two-body" system are really interesting. https://en.wikipedia.org/wiki/Lagrange_point They are places in space where the gravitational pull between two objects is balanced and basically zero. Think of being at the pivot point in a see-saw or teeter-totter. L4 and L5 are gravitational wells... think of the bottom of valley where something on the slope of the hill wants to roll to the bottom, but once there is stable and doesn't want to "roll out" of the valley. The other three, including L2 are "high points"... like the top of a mountain. When there, it's stable, but does require a little help to make sure it stays there. There are thrusters on NGST that will be able to give periodic nudges to make sure it stays there, but as a natural "balance point" these will be relatively small and infrequent. L2 is a stable and "quiet" location in space that is close enough to Earth that communication is relatively easy for the volume of data that will be downlinked, but far enough from the Earth-moon system that they won't interfere with or introduce unwanted background signal to the instruments.
Finally, and a little but of a brag, but one of the instruments on NGST was designed, built and will be "operated" from the University of Arizona. I know one of the people who was involved in the precision micro-soldering on the instrument. The whole "six degrees of separation" here is remarkably cool. Knowing someone who helped build a part of this is remarkable. I'd be beside myself if I were him knowing something I helped build was in space, will remain in space pretty much forever, and will be instrumental in astronomy for well over a decade would be beyond humbling. I can't wait to talk to him in a few weeks and see what he thinks about the last few days!
Your TV is watching you!View attachment 836522
Funny... I thought the JWST was a little more... complex.
Way to go, Google Ads.
Yeah, it's a lot. I've spent most of my professional career, and even going back to high school even, doing a lot of public outreach in astronomy. Those are very complex topics to try to make digestible by non-science folks.I didn't understand most of this. This shit is exciting!!!
You might be able to help me wrap my brain around this one then...Yeah, it's a lot. I've spent most of my professional career, and even going back to high school even, doing a lot of public outreach in astronomy. Those are very complex topics to try to make digestible by non-science folks.
It's a lot easier to explain in person than in text form. I can get a sense of where folks are stuck and can usually provide a little extra explanation.
I didn't mean to overwhelm everyone's heads, but to try to clarify a few fun things about the mission and the orbital ballet that's in progress and will continue once it gets on station.
L2 is a LaGrange point. It's a point in an object's orbit where the gravitational pull of the two largest nearby bodies essentially create a 'quiet point' graviationally in space.You might be able to help me wrap my brain around this one then...
I think I understand orbits. Stuff in space is propelled at a speed that it cannot break free of the gravity from the densest nearby object, but fast enough that is does not get pulled into the nearby object. I think of it as a football being thrown (but without wind resistance).
JWST is set to maintain an orbit around L2. However, there is no object in L2 that would "pull" JWST down. So how does JWST maintain this orbit, without constantly using fuel?
Video, in case anyone doesn't understand this weird orbit:
An eddy is a way of thinking of this that, while not 100% correct, serves as a good analogy. The Lagrange point are places where there is a balance of gravitational forces between two objects... in the case of Webb it's the Earth and the Sun. Get away from those points and one or the other is tugging on the object (asteroid, satellite, speck of dust, giant space telescope... whatever) and will make it want to drift from those locations.I guess I see a Lagrange point like an eddy in fluid dynamics, but clearly I'm mistaken. The point must have it's own gravitational pull then, based off the pull of the Earth and the Sun?
L2 is an imaginary point in space. That animation is exaggerated a bit for clarity as Webb won't make that big of a loop around that spot. Going back to my earlier Ted Talk (JWST is set to maintain an orbit around L2. However, there is no object in L2 that would "pull" JWST down. So how does JWST maintain this orbit, without constantly using fuel?
The other good news is that the Arianne rocket launched at a trajectory so close to optimal, that there is a ton of fuel left to make those tiny corrections for many years to come!An eddy is a way of thinking of this that, while not 100% correct, serves as a good analogy. The Lagrange point are places where there is a balance of gravitational forces between two objects... in the case of Webb it's the Earth and the Sun. Get away from those points and one or the other is tugging on the object (asteroid, satellite, speck of dust, giant space telescope... whatever) and will make it want to drift from those locations.
@buzzmonkey 's link is a very good description of these.
L2 is an imaginary point in space. That animation is exaggerated a bit for clarity as Webb won't make that big of a loop around that spot. Going back to my earlier Ted TalkLOL: :laugh
, using another analogy, all Webb will have to do at L2 is like a boulder on top of a hill. As long as it stays at the top, it will take very little effort (in this case fuel) to stay there. There will be a little wander about L2, but the little nudges to makes sure it stays there will be relatively easy (and goes to the happiness conveyed in the arstechnica link above).
Crazy orbital dynamics. I'm glad I don't have to wrangle those calculations more than once in a while, and even then, in a much less complicated manner. Two-body systems are easy to manage, but throw a third object in there, and things can get messy really fast!