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Webb flies Ariane 5: watch the launch live on 25 December
- foobarian 5y agoDecades of meticulous planning and they couldn't give their teams a day off on Christmas? Of course it could be that consensus was this beats any other kind of activity that day in which case fair enough. :-)
- jpgvm 5y agoI think spending Christmas wringing your hands unsure if your $10B decades-in-development baby is going to make it to orbit sounds incredibly stressful... It's going to be awesome for us to watch but I feel for all the folks that worked on this.
- ajross 5y agoFWIW: given the extraordinarily complicated mechanical design, merely reaching orbit is the "easy part". The real imagined disasters won't happen until the mirrors assemble.
- mortenjorck 5y agoTrue, though it’s also worth considering that Webb is going far beyond “orbit“ as we generally think of it. I don’t know how much has been launched all the way out to L2 before, but it’s probably an order of magnitude less than what’s in Earth orbit.
- ajross 5y agoMeh, but there's nothing to hit in space. The energy required to reach a routine geosynchronous orbit is already ~85% of escape velocity. The added boost is minimally more dangerous and the trip is just empty hours. "Time" does kill spacecraft, but not often. The Webb self-assembly is absolutely where the scary bits lurk.
- jpgvm 5y agoYeah valid. Though the whole "hurtling upwards on top of a bomb" part is still definitely scary in it's own right.
- argiopetech 5y agoParticularly given the launch record of the Ariane 5 platform. I did some quick research, and no modern launch platform has as high a mission failure rate (4.5%.) The Delta family comes close at 4.4%, but that's a 50yr launch history. The Delta 4 iteration has had no failures.
- jacquesm 5y agoAs I wrote elsewhere, the bulk of those failures were in the first 15 launches, after that it was a very long string of one success after another with one partial failure in 2018.
- krisoft 5y ago> I don’t know how much has been launched all the way out to L2 before... There is a handy list on wikipedia: https://en.wikipedia.org/wiki/List_of_objects_at_Lagrange_points#L2 https://en.wikipedia.org/wiki/List_of_objects_at_Lagrange_po... Your intuition is quite right, there is way less satellites parked around L2 than in low earth orbit for example. But that doesn't really pose too big of a challenges in itself. It is of course far, both distance wise and energetically. The main complication often mentioned is if something is wrong with the telescope it makes it very unlikely that a crew can visit it to fix it. The way for example how they repaired Hubble is unlikely to happen with Webb.
- Symmetry 5y agoThe Ariane 5 is batting 106 for 111 which is pretty good odds and perfectly respectable for a heavy lift vehicle... but not so much so that I don't wish it was launching on an Atlas 5 instead.
- GuB-42 5y agoAriane 5 had some early problems, the first failure even became a case study in critical software development. But it had only had one partial failure after the 17th launch: the payload was launched to the wrong orbit because the wrong coordinates were put in the computer. A huge QA problem but not the fault of the launcher which did exactly as told. Now, both Ariane 5 and Atlas 5 are extremely reliable, mature rockets.
- jacquesm 5y agoFour of those were in the first 15, the last recent one was in 2018, and was a partial failure.
- _ph_ 5y agoWell, according to the original planning it should have launched before Christmas. It was only the weather delaying it by one day. I guess once they were ready for the launch, they want to avoid to delay it any longer than needed. Not sure, how long the rocket can be "stored" in launch-ready state before it has to be serviced again.
- sp332 5y agoIt was scheduled for Wednesday and then postponed for bad weather.
- deleted 5y ago[deleted]
- furyofantares 5y agoNewton's birthday sounds like the perfect day for a rocket launch to me
- makira 5y agoHe was born January 4th, using modern calendars. https://www.britannica.com/biography/Isaac-Newton https://www.britannica.com/biography/Isaac-Newton
- furyofantares 5y agoOh cool, I get to celebrate his birthday twice per year now. That said, strangely enough, if the calendar changed after my death and people were still celebrating my birthday, I'd expect people to celebrate the day on the calendar I used rather than the accurate day.
- kibwen 5y agoSince Isaac Newton was actually born extremely prematurely, at less than 30 weeks of pregnancy, maybe he was the one rushing to match the date of the JWST launch. :P
- malermeister 5y agoLots of European countries celebrate Christmas Evening (Dec 24) more than Christmas Day (Dec 25).
- CoastalCoder 5y agoI wish for our Canadian friends that the telescope unfurls on Boxing Day.
- Ostrogodsky 5y agoYeah, 25th is the day to nurse the hangover
- jacquesm 5y agoIf you start planning your rocket launches around religious holidays then that is going to be a bit of a problem, there are just too many of them: https://nationaltoday.com/religious-holidays/ https://nationaltoday.com/religious-holidays/
- rrss 5y agoHow about planning around the single most celebrated holiday in the US, religious or not: https://en.m.wikipedia.org/wiki/Public_holidays_in_the_United_States https://en.m.wikipedia.org/wiki/Public_holidays_in_the_Unite...
- jacquesm 5y agoAriane 5 is a European effort, not a US effort, it will launch from French Guyana, not from the US. https://en.wikipedia.org/wiki/Ariane_5 https://en.wikipedia.org/wiki/Ariane_5
- rrss 5y agoCool. Webb will be monitored and operated by NASA in Maryland. https://en.m.wikipedia.org/wiki/James_Webb_Space_Telescope#Time,_budget https://en.m.wikipedia.org/wiki/James_Webb_Space_Telescope#T... https://en.m.wikipedia.org/wiki/Space_Telescope_Science_Institute https://en.m.wikipedia.org/wiki/Space_Telescope_Science_Inst...
- jacquesm 5y agoI really don't get your fixation about this: the people involved are all most likely extremely happy to see their creation fly and to have Christmas take a backseat to that. Let's just hope it all goes well, this is one of the most complex space endeavors we've ever tried, and if it fails it will have many negative long term implications.
- rrss 5y agoI did not get your real or feigned ignorance that Christmas is a much more significant holiday to the vast majority of the people involved than the Feast of the Ass. I also hope all goes well. Cheers.
- neals 5y agoI can't watch this. So many years and so many man-hours riding on top of a rocket is to much for me.
- C19is20 5y agoSimilar. But more because I can't believe they didn't build two - for redundancy.
- anotheryou 5y agoI wonder what time and cost a rebuild would have. Maybe half the original development costs?
- notjustanymike 5y agoAnd here I am, feeling nervous about a production web deployment.
- notjustanymike 5y agoUpdate: the rocket launch went better than my deploy.
- guerrilla 5y agoCountdown with links to livestream and blog here: https://www.jwst.nasa.gov/content/webbLaunch/countdown.html https://www.jwst.nasa.gov/content/webbLaunch/countdown.html
- ourmandave 5y agoIf you want to skip the Super Bowl pre-game, the actual launch window starts at 7:20 am EST (12:20 UTC) and lasts for 31 minutes. It can launch anytime during that window.
- _joel 5y agoA fantastic Christmas treat, best of luck to all the teams involved :)
- amichail 5y agoWhy isn't SpaceX doing this?
- varjag 5y agoThe project and the choice of contractors predates SpaceX.
- ddalex 5y agoSpaceX wasn't a thing when the project constraints were defined.
- NikolaeVarius 5y agoBecause the contracts were made before SpaceX was deemed reliable.
- adventured 5y agoThe launch partner/platform wasn't chosen recently and it's part of what ESA is providing as a partner in the program. "In exchange for full partnership, representation and access to the observatory for its astronomers, ESA is providing the NIRSpec instrument, the Optical Bench Assembly of the MIRI instrument, an Ariane 5 ECA launcher, and manpower to support operations. The CSA will provide the Fine Guidance Sensor and the Near-Infrared Imager Slitless Spectrograph plus manpower to support operations." https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Partnership https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Par...
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- kitd 5y agoAll the best to everyone working on this tomorrow. Hope you get some suitably generous TOIL in January.
- gfodor 5y agoInteresting they found a way to add a hidden risk variable to the launch, by sending it up on a day people are having to choose to not be with their families. Have a bad feeling about this :/
- deleted 5y ago[deleted]
- daenney 5y ago“They” didn’t find anything. It wasn’t originally planned for tomorrow. The weather found a way. There’s only so much wiggle room and launch windows.
- rrss 5y ago> It wasn’t originally planned for tomorrow Right, it was originally planned for 2007. It is sorta funny that after 14 years of delays they picked the week of Christmas.
- mrtksn 5y agoThey didn’t pick that either, it was supposed to launch earlier but a clamp broke down when attaching the telescope to the rocket sending vibrations all over it and and as a result they had to inspect for damages, further delaying the launch. Then the weather wasn’t good and delayed once more.
- rrss 5y agoThey did though. It was delayed, they chose to delay it from October to December 18 to December 22 to Christmas instead of like the first week of January or whatever. It’s not like this thing is launching to Mars and they’d have to wait a couple years if they miss this week - it could launch on 210 days of each year. https://jwst.nasa.gov/content/about/faqs/faq.html#launchWindows https://jwst.nasa.gov/content/about/faqs/faq.html#launchWind... I don’t mind at all, I just think it’s a bit funny.
- drunkonvinyl 5y agoThe original title “Webb flies Ariane 5: watch the launch live” has a nice ring to it. Here goes!
- jessriedel 5y agoAre there alternative streams that anyone here would recommend? The more technical, the better.
- dimtion 5y agoI do have a question about JWST that I wasn't able to find a fine answer in other forums. A lot of people and engineers are saying that the JWST is a marvel of engineering, with truly inovative technical solutions and a giant step up compared to Hubble Telescope. And it does seems like so! However, I'm always baffled how everyone seems proud that the telescope has something like 200 SPOF during deployment, and if even one of them fails the whole mission could fail. I know that each step has probably been throughoutly tested, and that the acceptable probability of failure of each one of those steps has been deemed acceptable. But I'm still surprised that people are proudly conflating excellent engineering with a design that has a large number of spofs. In my domain this would be considered as a terrible design (aka "hope is not a strategy"), even given the constraints of mass and volume that such project incur: 200 hundred low probability events, chained, can get in the realm of possible. I can't imagine JSWT team doing "bad engineering", so I'm sure I'm missing a piece. Is it only PR that underline this aspect? Is JWST as brittle as the news want to make us think? Or are there technical reasons or acceptable failure modes that gives confidence that those steps are not as critical as the news let us people know?
- darknavi 5y ago> However, I'm always baffled how everyone seems proud that the telescope has something like 200 SPOF during deployment, and if even one of them fails the whole mission could fail. I'm not sure I've seen anyone who is _proud_ of it, lots of people are just setting expectations. Probably due to the similarities with Hubble (although JWST can self-align it's mirrors!). It also might be posturing to show how well the thing is built. Space is hard, like really hard, and these agencies keep knocking it out of the park.
- nharada 5y agoI'm guessing it's a case where all the various extreme requirements simply do not allow for redundancy in the places the engineers would prefer to have it. The options are likely (1) okay performance with a lower chance of failure or (2) extreme performance with a higher chance of failure.
- jacquesm 5y agoUnlike say, the Apollo program, which had a guaranteed successful outcome? The thing to realize is that these are some of the hardest things humanity has tried their hand on and if it all works that's a great thing for all of us, if it fails we will learn something and we'll go back to the drawing board (but we won't have a JWST and that's a significant loss, besides the obvious future calls of 'look at what happened to JWST' which will no doubt have negative impact on finding funding for future space missions). Also, I think you're mistaken about people being 'proud about the 200 SPOFs', if they could have made it one less they certainly would have because everybody involved wants this to succeed. Think of these as the ones that they simply could not get rid of no matter how hard they tried.
- keewee7 5y agoHow much did NASA, ESA and CSA each contribute to this project?
- jacquesm 5y agoFrom the JWST wikipedia page: "In the 2005 re-plan, the life-cycle cost of the project was estimated at US$4.5 billion. This comprised approximately US$3.5 billion for design, development, launch and commissioning, and approximately US$1.0 billion for ten years of operations.[18] ESA is contributing about €300 million, including the launch.[84] The Canadian Space Agency pledged $39 million Canadian in 2007[85] and in 2012 delivered its contributions in equipment to point the telescope and detect atmospheric conditions on distant planets." https://en.wikipedia.org/wiki/James_Webb_Space_Telescope https://en.wikipedia.org/wiki/James_Webb_Space_Telescope
- gautamcgoel 5y agoThose numbers are completely obsolete; the final price tag was over $10B.
- jacquesm 5y agoThen maybe you should update that wikipedia page.
- geenew 5y agoThe CSA is contributing staff to operations as well, afaik. A more recent source says this (found through wikipedia). Values all appear to be up to launch, and do not include operations. NASA: 8,800m ESA : 850m CSA : 200m ------------ All : 9,850m (No epoch given to dollars; presumably they are 2021 USD) "Günther Hasinger, ESA director of science, estimated that Europe’s contributions to JWST, in the form of instruments and the Ariane 5 launch, to be about 700 million euros ($850 million), roughly the same as an ESA “M-class” science mission. Gilles Leclerc, director general for space exploration at the Canadian Space Agency, said Canada’s contribution of an instrument and fine guidance sensors cost the agency about $200 million Canadian ($165 million) over 20 years. “This is an investment in discoveries of the universe,” he said. NASA now estimates it will spend $8.8 billion on JWST through the spacecraft’s launch."[1][2] Those numbers line up with a summary the Planetary Society put out.[3] That source includes info on the operations cost, at least for the US: "The James Webb Space Telescope (JWST) is expected to cost NASA $9.7 billion over 24 years. Of that amount, $8.8 billion was spent on spacecraft development between 2003 and 2021; $861 million is planned to support five years of operations. Adjusted for inflation to 2020 dollars, the lifetime cost to NASA will be approximately $10.8 billion. That is only NASA’s portion. The European Space Agency provided the Ariane 5 launch vehicle and two of the four science instruments for an estimated cost of €700 million. The Canadian Space Agency contributed sensors and scientific instrumentation, which cost approximately CA$200 million." All three agencies will supply staff to support operations, which I guess makes sense since they've all contributed different instruments.[4] [1] https://spacenews.com/jwst-launch-slips-to-november/ https://spacenews.com/jwst-launch-slips-to-november/ [2] https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Cost_and_schedule_issues https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Cos... [3] https://www.planetary.org/articles/cost-of-the-jwst https://www.planetary.org/articles/cost-of-the-jwst [4] https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Partnership https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Par...
- ape4 5y agoFor people in North America 12:20 GMT is... 4:20 am PST 7:20 am EST Get up before the children ;)
- captn3m0 5y ago1750 IST in India
- BurningFrog 5y agoWe're told that since JWT will travel very far away before it unfolds and activates all its systems, there is no practical way to service it if something would go wrong. Why can't it unfold etc in Earth orbit, where a repair mission can be sent if needed, and then travel to its Lagrange point?
- ufmace 5y agoAbsent all of the other practical considerations, even in LEO, a repair mission would probably be so expensive that it would be cheaper to build and launch a new one instead.
- justin66 5y ago> Why can't it unfold etc in Earth orbit, where a repair mission can be sent if needed, and then travel to its Lagrange point? Another comment mentioned that it's not designed to accelerate while it's fully deployed, and that's true enough. You'd wreck it. The other essential thing is that there's no way to give it and its instruments anything like their designed operating parameters (pretty hot on one side of the sunshade, something like 40 kelvin on the other side) in Earth orbit.
- mabbo 5y agoIt's a problem of energy and orbits. To get from low-earth orbit to the sun-earth Lagrange point 2 (where the JWT is headed) takes around 7 km/s of delta-v[0]. That's a lot of speed. You could try to do this gently enough that the unfurled JWT won't be damaged by the acceleration. This isn't totally impossible, but you'd need a good Hall thruster (ion engine) with a huge amount of reaction mass, since the JWT is so big itself. It would need to run for longer than any other such thruster has. It would need massive solar panels to power it.[1] Or you could have the original rocket just be bigger, and throw it all the way to the right orbit while everything is packed tight. [0] https://en.wikipedia.org/wiki/Delta-v_budget https://en.wikipedia.org/wiki/Delta-v_budget [1] I'm guessing at this, but that's my intuition. I encourage anyone to correct me because space is too cool to be upset that I was wrong.
- deleted 5y ago[deleted]
- Ankaios 5y agoIt's humanity's self-unwrapping Christmas present.
- Mesisio 5y agoWill this be visually tracked? Like can we watch it to it's journey?
- Sosh101 5y agoPersonally I hate launching anything around the Christmas period.
- mulcahey 5y agoLaunchHN: JWST on Christmas