[HN Gopher] JWST Launch NASA Livestream
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JWST Launch NASA Livestream
Author : grecy
Score : 138 points
Date : 2021-12-25 10:30 UTC (12 hours ago)
(HTM) web link (www.youtube.com)
(TXT) w3m dump (www.youtube.com)
| ravisutrave wrote:
| "Webb will soon begin an approximately two-week process to deploy
| its antennas, mirrors, and sunshield."
|
| https://twitter.com/NASA/status/1474724928360525827
| magicalhippo wrote:
| Anyone know why the trajectory dipped down during the second
| stage? To gain extra orbital velocity or something? Been too long
| since I played Kerbal Space Program.
| Sosh101 wrote:
| Yeah I guess it was something like a partial slingshot?
| instagraham wrote:
| I wonder what the Eye of God will look like through this
| telescope. It's much farther out than Hubble.
| chinathrow wrote:
| I had to look this one up -
| https://en.wikipedia.org/wiki/Helix_Nebula
| ryzvonusef wrote:
| launch looks good!
| ryzvonusef wrote:
| https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html
| perihelions wrote:
| 32 minute launch window starting at 12:20 UTC (07:20 EST). When
| this comment's indicated age is ~30 minutes.
|
| https://blogs.nasa.gov/webb/2021/12/21/james-webb-space-tele...
| Jellyspice wrote:
| Countdown page
| https://jwst.nasa.gov/content/webbLaunch/countdown.html
| [deleted]
| junon wrote:
| Either going to be a huge, incredible, historic event, or a
| massive Christmas Day tragedy. Hoping for the former - good luck
| NASA!
|
| E: Wow, the coverage about the hurricane causing leaks in the
| buildings is wild. The pictures of tarps over computer desks
| makes me unreasonably uncomfortable.
| 1_player wrote:
| My hope is that if it's the latter, building a new JWST from
| scratch will not take as much time and money as designing the
| first prototype did. I hope they have kept really good notes
| and backups :-)
| jacquesm wrote:
| It worked!
| dredmorbius wrote:
| Good launch.
|
| And over 472k viewers on the livestream. Good service by YouTube.
|
| (I don't get to praise them often, credit where due.)
|
| All launch events seemed precisely on schedule and trajectory.
|
| The 2nd stage even caught the solar panel deploy on camera, which
| I believe was an unexpected bonus.
|
| Now we've got 30 days of deployment events, another 300 or so
| SPOFs to clear. Arrival at L2 in a month.
|
| Six months to chill and calibrate (with or without Netflix I'm
| not sure).
|
| Science starts in June.
| jacquesm wrote:
| > 472k viewers on the livestream
|
| We had about 11K on STS 82, which I still think was the high
| point of my career. Back in the day with capacity being what it
| was that put a serious strain on the internet as a whole,
| shortly after that we had to move to the other side of the
| Atlantic be able to continue to operate.
| shireboy wrote:
| Great anecdote!
| jacquesm wrote:
| https://twitter.com/jmattheij/status/1474767067236777991
| kurthr wrote:
| I was a little disappointed, because I'd watched the animation
| last night.
|
| The only differences were in the first 4 seconds (before it hit
| the clouds) and after the spring launch, when we caught the
| solar panel deploy in the sun with earth below from the 2nd
| stage. At least everything went as planned!
|
| I was surprised at the timeline and how rapidly it slows before
| reaching the L2 orbit. It's already fallen from 4mps to 1.7mps
| in the first few hours. Even though it takes 30 days to reach
| L2, it will be 30% of the way there in the first day.
|
| https://webb.nasa.gov/content/webbLaunch/whereIsWebb.html
| kingofpandora wrote:
| From the broadcast: "Liftoff from a tropical rain forest at the
| edge of time itself."
|
| What does that mean?
| sjburt wrote:
| It was "to the edge of time itself" which I guess is some kind
| of reference to the telescope being able to observe the early
| universe? It seemed kind of cheesy.
| jacquesm wrote:
| It is 'to the edge of time' and what they mean with it is that
| the JWST can look very far back into our past to the earliest
| days of the universe with its instruments that are capable of
| observing severely red-shifted wavelengths.
| 95014_refugee wrote:
| It means that someone was paid to talk, because radio dies
| hard.
|
| The idea that commentary should be informative and that content
| can speak for itself is (still) deeply threatening to many
| folks in the broadcast industry. See any sports broadcast for
| examples.
| nabla9 wrote:
| Super exiting.
|
| * JWST costs ~$10B, about the same as Large Hadron Collider or
| aircraft carrier.
|
| * JWST has 344 single-point-of-failures (SPOF), 80% of them
| related to deployment.
|
| * No ability for repair. JWST goes to orbit the Sun 1.5 million
| kilometers away from the Earth, almost 4 times the distance
| between Earth and Moon.
|
| * Ariane 5 launch failure rate is 0.045
|
| ---
|
| assuming 0.045 launch failure probability, and 0.0001 failure
| probability for each SPOF, the mission failure probability is
| ~8%. 0.955x(1-0.0001)^344
| efitz wrote:
| I'm much more concerned about what will happen once the
| telescope is in operation. We can't send astronauts to L2 to
| fix it like we could send them to Hubble on STS.
| pfdietz wrote:
| We can't yet, but doing so isn't entirely out of the
| question. It's easier than sending anyone to Mars. The one-
| way trip time for astronauts to L2 might be 25 days.
|
| https://www.wired.com/2012/04/100-day-mission-to-sun-
| earth-l...
| api wrote:
| JWST apparently does have some kind of docking attachment
| so we can service it if we get the capability between now
| and EOL. Servicing once could likely double its useful
| life. Starship and Orion could do it AFAIK. Maybe Dragon
| with a service module.
| mlindner wrote:
| The docking attachment was originally planned but there's
| been no mention of it in the last 10 years or so and no
| pictures of such an attachment point. They probably de-
| scoped it.
| redisman wrote:
| I'm guessing they can't service it by adding more fuel?
| That would've been a neat expansion to be able to expand
| its life
| wiz21c wrote:
| This makes a 92% success rate... I'm not sure I would cross a
| road if I had that much chance to be hit by a car :-)
| guerrilla wrote:
| > 0.0001 failure probability for each SPOF
|
| Why did you choose this value for the assumption? Is that
| standard or a publicized detail?
| nabla9 wrote:
| I picked relatively high number 1/10000 as a starting point
| to get a ballpark. NASA has never tested deployment in the
| zero gravity. It's unlikely that the probability is higher.
|
| Ariane launch failure probability dominates if you add zeros.
| 0.00001 -> 4.8% 0.000001 -> 4.5%
| marcodiego wrote:
| Why there's no "narration"? Looks like nasa tv employees are out
| on holidays?
| guerrilla wrote:
| The event hadn't started when you looked. Check now.
| Symbiote wrote:
| Additional comments on the ESA livestream (posted a few minutes
| before this one): https://news.ycombinator.com/item?id=29681636
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(page generated 2021-12-25 23:01 UTC)