[HN Gopher] James Webb telescope reaches its final destination i...
___________________________________________________________________
James Webb telescope reaches its final destination in space,
million miles away
Author : pseudolus
Score : 643 points
Date : 2022-01-25 10:44 UTC (12 hours ago)
(HTM) web link (www.npr.org)
(TXT) w3m dump (www.npr.org)
| _joel wrote:
| I really can't wait until the have proper first light. They say
| June will be the earliest after phasing has completed, but it
| can't come soon enough.
|
| That being said, I've waited 25 years so far, a few more months
| won't hurt
| spookthesunset wrote:
| I'm sure there will be "test photos" that get published in the
| interim. I'd be seriously disappointed if there wasn't.
| ashes-of-sol wrote:
| beiller wrote:
| Yes does any one know when first light photos will appear? I
| know it is very unknown but I've seen many NASA employees
| live suggest there will be some interim first light photos to
| come and I am super excited to see them.
| samwillis wrote:
| If any of the James Webb team are here, Congratulations! A
| phenomenal achievement.
|
| So excited to see first images and read about all the discoveries
| you are going to make. Exciting times!
|
| My daughters (7yo) class have been talking about it, she keeps
| coming home from school excited to tell me about the latest
| update on its journey. I love the fact we have these exciting
| things happening in space science to experience together.
| pfdietz wrote:
| I'd be happier in a world where individual universities, or at
| least consortiums, could have their own space telescopes.
| LeonM wrote:
| The JWT is famous for costing over 10b USD to develop. AFAIK
| it's the most expensive object ever to be launched into space.
|
| I don't think universities should (or could) spend that kind of
| money on research equipment.
| joshuahedlund wrote:
| Why can't universities launch space telescopes that don't
| cost as much as the most expensive one ever?
| andrepd wrote:
| The ISS has cost a combined total of 150b$. It's apples and
| oranges, of course, but it can considered to be the single
| most expensive item ever built.
| nerfhammer wrote:
| It's one of the most expensive objects period
| pfdietz wrote:
| If launch costs are 1% or less per mass of the Ariane 5, mass
| budgets could be greatly increased, and engineering could
| become easier. I see no reason ultimately why space
| telescopes should be much different in cost than terrestrial
| telescopes. Ultimately I see telescopes being maintained and
| upgraded in space much as terrestrial telescopes are.
| panda-giddiness wrote:
| The Webb telescope didn't go several times over budget from
| growing several times heavier. Novel telescope are
| expensive because they must address unique engineering
| challenges with unforeseen costs. You can't just grab a
| sunshade off the shelf - everything's built bespoke.
|
| Of course, the flip side here is that it would be cheaper
| to build a second Webb telescope. Maybe we could mass
| produce a hundred more for a tenth the cost, but it's not
| clear that would be a hundred times better for astronomy.
| edgyquant wrote:
| With lowered launch costs, and more things launched into
| orbit, surely over time you'd have to handle these unique
| engineering challenges yourself less and less.
| pfdietz wrote:
| That's not what I was implying. I'm implying the mass
| (and volume, and especially servicability) constraints
| required expensive engineering. Those constraints are
| relaxed with much cheaper launch, especially if in-space
| assembly and maintenance (by astronauts!) becomes
| affordable.
| spookthesunset wrote:
| I hear what you are saying--if launches were easy they
| could have dropped a bunch of expensive constraints. But
| consider that if launch costs were truly the bottleneck
| for JWST, they'd have just thrown more money at the
| launch budget and got a bigger / fancier rocket. I'm no
| rocket science person but I'd assume you can scale launch
| capacity by throwing more money at it--it's generally a
| solved problem whose risks are much better understood
| than whatever JWST is doing. It makes sense to throw
| money at things to reduce risk like larger launch
| vehicles, regardless of their cost.
|
| JWST is expensive because it does stuff that has never
| been done before. Lots of "unknown unknowns" that you
| need to make "known unknowns" Anything like this will be
| expensive--same is true for software even. You are
| working in uncharted water--risks are everywhere.
|
| If they could have dropped a bunch of their constraints
| and reduced program risk by throwing money at a fancier
| launcher, they'd have done it. The fact they didn't
| suggests that the cost & risk wasn't constrained by the
| launch.
|
| Now maybe you could argue that "if there was only a way
| to make it serviceable using cheap rockets"--then yeah
| maybe they could drop some of the more expensive and
| risky constraints. But however many years ago when this
| project started, such a thing was not even on the
| horizon. Only in the last few years has such a thing even
| begun to seem feasible. Perhaps future missions can relax
| their constraints because suddenly technology makes
| repair "easy". But JWST didn't emerge in that
| environment.
| NikolaeVarius wrote:
| Its nice to be able to design things around Sci-Fi.
| However, still in 2022, there is no spacecraft that
| allows EVAs anywhere.
| jacquesm wrote:
| The occupants of the ISS beg to differ.
|
| http://spaceref.com/iss/eva.html
| NikolaeVarius wrote:
| I was unaware that the ISS was a spacecraft. I was under
| the impression it was a space station.
|
| Im also unaware that the ISS is able to reach L2 or
| really any orbit other than LEO roughly 400km in
| altitude.
| jacquesm wrote:
| > I was unaware that the ISS was a spacecraft.
|
| I can't really help that, but here is a nice page from
| NASA:
|
| https://www.nasa.gov/audience/forstudents/5-8/features/na
| sa-...
|
| "The International Space Station is a large spacecraft in
| orbit around Earth."
|
| > Im also unaware that the ISS is able to reach L2 or
| really any orbit other than LEO roughly 400km in
| altitude.
|
| You can tow it wherever you want, provided you attach a
| suitable propulsion device. That's also how it stays in
| that orbit, every now and then they boost it back up to
| offset the orbital decay.
|
| Also: in space assembly could take place _in orbit_ and
| then when the device is complete it can be sent off to
| L2. The problem with such a scheme is when things break
| down after the transit to L2.
| Rebelgecko wrote:
| Johns Hopkins University is playing a fairly large role in the
| JWST mission
| tobylane wrote:
| Cubesats fill that role, for when those groups need their own.
| JWST is from the consortium of half the first world, because
| they want to measure the same thing. It's not an either-or.
| pkdpic wrote:
| I had no idea its final destination was a legrange point thats so
| cool!
|
| I got confused though, I thought they were saying it was at the
| one between the sun and the earth (L1). But I guess its at the
| one behind the earth (L2)? Anyway so cool! Lagrange points always
| make me think of Liu Cixin :^)
|
| > The L2 point of the Earth-Sun system was the home to the WMAP
| spacecraft, current home of Planck, and future home of the James
| Webb Space Telescope. L2 is ideal for astronomy because a
| spacecraft is close enough to readily communicate with Earth, can
| keep Sun, Earth and Moon behind the spacecraft for solar power
| and (with appropriate shielding) provides a clear view of deep
| space for our telescopes. The L1 and L2 points are unstable on a
| time scale of approximately 23 days, which requires satellites
| orbiting these positions to undergo regular course and attitude
| corrections.
|
| https://solarsystem.nasa.gov/resources/754/what-is-a-lagrang...
|
| ^ cool lagrage point graphic and nasa explanation
| ainiriand wrote:
| 'Science' writing at its worst -> the tennis-court sized
| telescope made its way into a parking spot that's about a million
| miles away from Earth.
|
| It would be better to try to explain concepts in a succinct way
| and, if it is not possible, to provide links to get the full
| information about a more detailed description. Also it is a good
| idea to use metric units for science articles.
| Denvercoder9 wrote:
| _> Also it is a good idea to use metric units for science
| articles._
|
| It's not if you're writing for an American audience that's more
| familar with imperial units.
| acheron wrote:
| They're not "imperial" units, since those were set by the
| British Empire in the first part of the 1800s, and the
| Americans never adopted them.
| mulmen wrote:
| _Pushes up glasses_. Well, actually, the United States of
| America has never used Imperial Units. We have used US
| Customary Units which share some of the more common names.
| But the definitions and sizes are not the same, nor are all
| the names. Also, since 1893 US Customary Units have been
| defined in terms of SI units.
|
| https://en.m.wikipedia.org/wiki/Mendenhall_Order
| https://en.m.wikipedia.org/wiki/Metric_Act_of_1866
| https://en.m.wikipedia.org/wiki/Imperial_units
| ainiriand wrote:
| Then you can use football fields as measurement unit,
| following that argument. Or bananas.
| irrational wrote:
| But tennis courts are very common in America. Every high
| school around here has at least 2. Many parks have them.
| The fitness center I go to has 2 external and 1 internal
| tennis courts.
| thret wrote:
| 'Football fields' seem particularly vague as there are half
| a dozen different sports called football, and each of these
| have different sized fields.
| ainiriand wrote:
| There are quite a few miles too:
| https://en.wikipedia.org/wiki/Mile_(disambiguation)
| marcosdumay wrote:
| Yeah, and there used to be more. That's why people
| standardized the meter.
| Denvercoder9 wrote:
| There's a reason things like football fields are commonly
| used as measurements in science communication: it actually
| helps the average person to get a sense of scale.
| [deleted]
| spaetzleesser wrote:
| But it also makes it impossible to compare things. A lot
| of these articles switch from tennis court to football
| field to school bus to width of a hair. I would be ok if
| they wrote something like "100m long which is about the
| size of a football field". But I really hate that they
| omit the numbers. I have no idea how many tennis courts
| fit into an football field and how that translates to
| school buses. And I bet most people don't know either.
| But I know that 30 meters fits 3.3 times into 100 meters.
| This kind of writing manipulates people and keeps them
| dumb.
|
| The same happens in politics. They often omit that when
| they write that something costs 100 billion that this is
| actually over 20 years. Another time they bring up a
| number that's over 5 years 1 year. Whatever is more
| convenient for the story.
|
| All this writing seems designed not to educate and inform
| but to keep people dumb and to appeal to the emotions the
| author wants to effect.
| andrepd wrote:
| Does it make a difference if it's 100m or 110m or 90m??
| For a general audience? Obviously it does not, the point
| is to convey the scale/order of magnitude. Is it about
| the size of a person? An elephant? A bus? A football
| pitch? That's what is being communicated here.
| p1mrx wrote:
| We should just define that outer space uses metric units. The
| average american won't know the difference between "a million
| miles" and "a million kilometers", because they're both way
| beyond the realm of practical experience.
| mulmen wrote:
| As an American, about 1.6.
|
| 600,000 kilometers is 1.5 times as far from Earth as the
| Moon. Interesting to think how much longer it took Webb to
| cover that distance than Apollo. A consequence of not being
| able to slow down under power.
| p1mrx wrote:
| JWST is around 1.5 million km, but that just illustrates
| my point. Being off by a factor of two makes no practical
| difference if you're not working on the mission.
| mulmen wrote:
| Haha, I multiplied by 0.6 instead of 1.6. Good enough to
| crash a climate orbiter.
| drawkbox wrote:
| We are all living vicariously through the good news of the James
| Webb space telescope successes. Some much needed good news that
| is based on the innovative push that humanity has. The good side
| of our human condition.
| hi41 wrote:
| The NPR posting does now provide information as to how the image
| was taken and I wondered how this image came about. This page
| describes how the picture of JWST was taken. It was taken by the
| rocket after it separated.
|
| https://www.flickr.com/photos/nasawebbtelescope/51775886252/...
|
| >>Here it is: humanity's final look at the James Webb Space
| Telescope as it heads into deep space to answer our biggest
| questions. Alone in the vastness of space, Webb will soon begin
| an approximately two-week process to deploy its antennas,
| mirrors, and sunshield. This image was captured by the cameras on
| board the rocket's upper stage as the telescope separated from
| it. The Earth hover in the upper right. Credit: Arianespace, ESA,
| NASA, CSA, CNES
| PinkMilkshake wrote:
| I'm a little embarrassed to say this and I don't know exactly
| what I pictured in my head, but I had no idea these telescopes
| were so big[1].
|
| I guess I never saw one pictured next to a human. I've only seen
| pictures of satellites being worked on so I expected something
| more human sized? It seems so stupid now, especially since earth
| telescopes are huge.
|
| [1]
| https://svs.gsfc.nasa.gov/vis/a010000/a013500/a013522/JWST_v...
| D_Guidi wrote:
| just enjoy, if you have a disney+ account, the documentary
| "among the stars" where you can view the astronauts repairing
| the hubble telescope
| 83 wrote:
| The nasa image[1] of employees with the scale model provides a
| better sense.
|
| [1]
| https://www.astronomie.nl/upload/750x498/images/Telescopen/J...
| inamberclad wrote:
| The space shuttle blows my mind every time I see one. It's huge
| - the size of an airliner - and would glide back at Mach 25.
| It's a humbling level of accomplishment.
| gillytech wrote:
| You can actually go see Endeavor in real life at the L.A.
| Science Center. Admission is like $2. Regardless of the size,
| the spectacle is breathtaking.
| bdamm wrote:
| I traveled to LA once just for the sole reason to see the
| space shuttle there. It was worth it!
| caycep wrote:
| I remember when it was decommissioned and flown to LA on
| the 747 transporter...definitely an event. They
| publicized the flight path and times, and did like 2 or 3
| loops over LA and the west side. Everyone in the city was
| watching on the rooftops of all the office buildings and
| parking garages.
| papito wrote:
| Standing next to a shuttle is a humbling experience. On TV
| it looks like, well, a plane, but in person, it's just
| _massive_. The exit hatch (I assume), the one you would
| expect an astronaut to exit while fully equipped and
| layered, looks like the size of a bottle opening.
| gameswithgo wrote:
| original plan was smaller, but military had a mission in mind
| that required it be bigger, so they went bigger to get
| military buy in. And of course the imagined mission never
| happened. I wonder how much money would have been saved!
| amelius wrote:
| Russians had the Buran, with more or less the same
| dimensions.
|
| https://en.wikipedia.org/wiki/Buran_(spacecraft)
| wongarsu wrote:
| I've heard the (probably unfounded) story that the
| Soviets saw the Space Shuttle, couldn't figure out why
| the Americans would build it but figured there surely
| must be a good reason; so they copied it to also have
| whatever capability the Americans were after.
| toomuchtodo wrote:
| Buran was also superior in capabilities; greater lift
| capacity, ability to transport more people, and attain
| higher orbits. It could also perform a mission entirely
| autonomously.
|
| The US Space Shuttle was the (heavy) inspiration, but the
| Soviets put their own spin on it.
| wolverine876 wrote:
| It had one test flight. Hardly comparable to a system
| which had (six?) models fully deployed and operational.
| ch4s3 wrote:
| That's the second mover advantage right?
| toomuchtodo wrote:
| That's part of it (with regards to rocket motor tech).
| The other is that the Soviet's designed the vehicle
| through a different process, versus the American's where
| it was design by committee (between NASA and the DoD
| [1]).
|
| [1] https://en.wikipedia.org/wiki/Space_Shuttle_design_pr
| ocess
| dharmab wrote:
| According to a book cited on the Wikipedia page on the
| Buran program, the Soviets looked at the shuttle's
| payload capacity and concluded it could be used to deploy
| military weapons into orbit.
| jandrese wrote:
| Any orbital rocket can deploy weapons into orbit. The
| Shuttle was unique in that it could theoretically capture
| a satellite and return to Earth with it.
| cronix wrote:
| It's not unfounded, and they knew about it before it ever
| flew once. A family member was in the CIA at the time
| (later at NSA and RAND) and played a role after they were
| sent to the USSR after graduating college to study
| Russian (paid for by CIA, they know 8 languages). They
| translated the technical Russian Buran plans/documents
| and decoded them for our scientists to compare to their
| own, as well as help slip design flaws into plans they
| knew would get stolen (because they knew who was stealing
| them from Nasa). They met with the president over the
| issue multiple times. True story. They were also involved
| in every stealth program until they retired in the early
| 2k's. They were in the pentagon when the plane struck on
| 9/11. I really wish I could get them to talk more or
| write a book lol. [Using "they" to avoid gendering family
| member]
|
| The Soviets (at the time) didn't "copy" it. They stole
| the plans and made it from them, adding in a few
| alterations, although the plans they stole were
| purposefully flawed.
|
| If you're up for it, you can visit the Buran's in their
| final resting place in Baikonur. They're just sitting
| there rotting away. Here's a video of some kids who broke
| in and had some fun exploring:
| https://www.youtube.com/watch?v=-q7ZVXOU3kM
|
| Article about the Soviet's espionage to get the plans:
| https://www.19fortyfive.com/2021/12/buran-how-russia-
| stole-t...
| wolverine876 wrote:
| They told you about these highly classified operations?
| FredPret wrote:
| There's a fantastic book about the stealth program by the
| former director of the Skunk Works, Ben Rich
| aksss wrote:
| In re the youtube vid, that's a flippin' huge hanger.
| Crazy that this stuff is sitting dormant.
| barkingcat wrote:
| re military mission never using the size, there could
| always have been classified payload launches that ended up
| using it.
| echelon wrote:
| > And of course the imagined mission never happened.
|
| There were 11 classified (ten successful) DoD space shuttle
| missions:
|
| https://www.space.com/34522-secret-shuttle-missions.html
|
| That's roughly 8% of shuttle missions.
| macintux wrote:
| The mission I believe the parent comment was referring to
| was a foreign (Soviet) satellite recovery. It required a
| larger payload bay and as I recall a very aggressive
| launch profile that I believe also imposed some
| undesirable design constraints, but my memory is fuzzy.
| bewaretheirs wrote:
| My understanding was that the specific requirement was
| for a launch into polar orbit (southbound from Vandenberg
| AFB, just north of Los Angeles) and then a landing ~90
| minutes later at Vandenberg, clearly to snatch something
| out of orbit.
|
| Since the earth is rotating under the orbital plane of
| the shuttle, this requires a large amount of cross-range
| maneuverability on reentry so it could land back in
| California rather than ~22.5 degrees west of Vandenberg
| in the pacific ocean, and this required large wings.
|
| I don't believe it's known for certain outside of
| classified circles _what_ was to be brought back. One
| theory was that it was to snatch a Soviet spy satellite
| out of orbit, but it 's entirely possible given the
| timelines that the classified requirement was to pull a
| film cartridge from a US spy satellite in polar orbit and
| return it quickly to earth for processing.
| echelon wrote:
| > I don't believe it's known for certain outside of
| classified circles what was to be brought back.
|
| Given that many details of the keyhole program were
| recently declassified [1], is there any chance we'll get
| to know the true nature of the shuttle program? (And if
| so, when might it happen?)
|
| [1] (a decade ago)
| https://en.wikipedia.org/wiki/KH-9_Hexagon
| samstave wrote:
| >> _the imagined mission never happened_
|
| The X37s would like a word. Also, "Rods from God" has
| something to say
|
| https://en.wikipedia.org/wiki/Boeing_X-37
|
| https://endwar.fandom.com/wiki/Kinetic_Strike
|
| ---
|
| Rods from god may be the source of "jewish space lasers"
| <-- the comment by a senator on how the wild-fires have
| been started in US and AU, meaning that a tungsten rod from
| space rained down molten tungsten to start fires...
|
| Fun stuff to speculate on.
| simonh wrote:
| The mission being referred to was capturing a Russian
| satellite in a polar orbit in the cargo bay and returning
| it to earth. The shuttle also needed big wings to provide
| the cross-range capability it would need to complete one
| polar orbit and land at the original launch point
| (Vandenberg) despite the earth having rotated, moving the
| airbase by many hundreds of miles since takeoff.
|
| The original NASA spec had a smaller cargo bay and wings
| because it would have mainly been a crew ferry. As a
| result it would also have been launchable on top of a
| rocket instead of strapped to the side, giving better
| safety. Significant cargoes would have been launched
| independently.
| tobylane wrote:
| What was the intended mission? I've read about the
| classified missions that went ahead, iirc one of them did
| use the full capacity.
| messe wrote:
| The one that had the biggest influence on the design of
| the shuttle was probably the plan to launch into a polar
| orbit, rendezvous with a satellite, capture it, and land
| as it swung around for the next orbit. This require
| massive cross-range capability, in order to be able to
| glide back to a suitable landing site in the US, putting
| lower limits on the size of the wings.
| walrus01 wrote:
| they spent a huge amount of money building a launch
| facility for it at Vandenberg that was never used. Got
| cancelled after the Challenger exploded.
| adolph wrote:
| Scott Manley has a wonderful explainer on it "The Most
| Important Space Shuttle Mission Never Happened":
|
| https://www.youtube.com/watch?v=_q2i0eu35aY
| echelon wrote:
| The classified autonomous X-37 [1] has a cargo bay [2]
| and there are (were?) plans to scale it up to double the
| size to accommodate larger payloads and crewed missions
| [3].
|
| [1] https://en.wikipedia.org/wiki/Boeing_X-37
|
| [2] https://www.thedrive.com/the-war-zone/36440/this-is-
| our-firs...
|
| [3] http://www.spacesafetymagazine.com/aerospace-
| engineering/spa...
| spookthesunset wrote:
| That X-37 photo in the wiki article had me go down the
| "payload fairing" rabbit hole. Still don't quite know
| what the "bubble wrap" is on the inside. I assume it is
| part insulation to protect from extreme heat and part,
| well, bubble wrap.
|
| According to wikipedia those things cost around $6
| million to manufacture and spacex was the first to ever
| bother retrieving them.
|
| https://en.wikipedia.org/wiki/Payload_fairing
| aksss wrote:
| Gosh, the section on "Mission failures caused by payload
| fairings" is understandable but not something I've ever
| heard of before. The launch crew error of failing to
| remove two lanyards.. ugh. To be "that guy" must've
| sucked.
| ddalex wrote:
| Likely snatching enemy satellites in a single orbit (i.e.
| launch, snatch sattelite, land, all in the same orbit)
| before enemy can even detect that the shuttle is up
| there.
| enave3 wrote:
| > What was the intended mission?
|
| There were several. A couple of examples: the shuttle
| could delay release of a payload, maneuver while in
| orbit, release the payload, then maneuver again. So
| conceptually, you just put a satellite into an orbit and
| your enemy doesn't know exactly what orbit its in. I'm
| sure eventually they would find it, but the military
| still wants stuff like that.
|
| Another example is the ability to grab a satellite and
| bring it back to Earth. To my knowledge, this was only
| ever used with the "long-duration exposure facility"
| because it'd probably be considered an act of war to
| steal another country's satellites but here again, it's
| the kind of thing the military would ask for.
| kzrdude wrote:
| Isn't the shuttle so big that it would be easy to track
| and see it?
| gameswithgo wrote:
| No idea, but yes I assume other missions managed to use
| the full capabilities once it was big!
| spaetzleesser wrote:
| The space shuttle is a sad story. On the one hand the
| military's money made it possible but they also influenced
| the design in a very bad way.
| BurningFrog wrote:
| A pretty typical big government project to me. Lot's of
| power centers pulling in different directions, little
| focus on actual needs.
|
| Space X does better work in part because it can make its
| own decisions and focus on long term goals.
| wolverine876 wrote:
| That's the stereotype of government promoted by private
| business like SpaceX, so they can get the funding shifted
| from NASA to them. But no private business has
| accomplished in space anything approaching what
| government has. NASA has been spectacularly successful,
| orders of magnitude beyond any explorers in human
| history.
|
| We're talking about just one of many successses on this
| page.
| gameswithgo wrote:
| This is the case with almost all large scale human
| endeavors. To get things done with lots of people takes
| compromises. Apollo program was the same way. I assume
| the pyramids and roman roads and so on as well. Though to
| be fair at some point once the shuttle program got going
| someone could have aborted on it and said that really
| this doesn't make sense.
| ethbr0 wrote:
| And the Mercury program, which launched on adapted
| Redstone ICBMs [0], themselves improvements on V-2s.
|
| An unfunded project that never gets built is objectively
| worse than a military-funded project.
|
| [0] https://en.m.wikipedia.org/wiki/PGM-11_Redstone#Redst
| one_der...
| whatshisface wrote:
| If the military-funded project creates $1M worth of value
| using $1B of funds, the unfunded project is objectively
| better.
| throwawayboise wrote:
| And sweeping von Braun's Nazi complicity under the rug
| while others were hanging from the gallows at Nuremberg.
| spaetzleesser wrote:
| As A German this really bugs me. Von Braun and friends
| knew exactly what was going on in their production
| facilities, didn't care and never had to confront their
| role in this.
| jrockway wrote:
| "Once the rockets are up who cares where they come down,
| that's not my department"
| https://www.youtube.com/watch?v=QEJ9HrZq7Ro
| meepmorp wrote:
| don't say that he's hyp-o-critical, say rather that he's
| a-po-litical
| ethbr0 wrote:
| (For those who aren't familiar with 1967 humor:
| https://m.youtube.com/watch?v=QEJ9HrZq7Ro&t=17s )
| adamc wrote:
| Right, this is basically a "human politics" thing.
| toss1 wrote:
| OTOH, they also influenced it in many good ways that you
| don't hear about.
|
| E.g., my astronomy professor mentioned to me in a
| conversation that the original design for the Hubble was
| smaller due to expected budget, but that it got up-sized
| because it turned out that they could piggy-back off of
| other relevant military development, and iirc, that went
| beyond just the larger available size of the shuttle bay.
| bbojan wrote:
| In perspective, you should keep in mind that the Space
| Shuttle was a failure as a launch vehicle, both in terms of
| safety and economics.
| NikolaeVarius wrote:
| And yet it allowed capabilities that we have lost in 2022.
| iamcreasy wrote:
| Actually one of the reason SS was not cost effective anymore
| because of the added complexities required by the DoD.
| vermontdevil wrote:
| To show the comparison (737 for example here)
|
| https://icdn2.digitaltrends.com/image/shuttle-948x1500.jpg?v.
| ..
| JorgeGT wrote:
| Well, the 737 is probably the worst aircraft to compare
| against, given it has been enlarged by 50% from the
| original 737-100 to the newer 737-900! https://upload.wikim
| edia.org/wikipedia/commons/b/bc/B737Fami...
| titzer wrote:
| Those size comparisons are super misleading. I've seen the
| shuttle and it's not that big. A 737 is pretty small. The
| shuttle can ride piggy-back on a 747--in fact it was
| designed to:
|
| https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-0
| 1...
|
| Also, the comparison with the Statue of Liberty is also
| misleading. The Statue of Liberty is on a huge pedestal
| that makes it stand much, much higher; the orbiter and
| boosters wouldn't reach the top of the SoL.
| lucideer wrote:
| The sum of your comment seems to be the subjective belief
| that the statue of liberty and 737s are "not that big"...
|
| Not sure what size you'd expect the shuttles to be, but
| being in the same ballpark as the statue of liberty
| (without pedestal) seems a great deal larger than my
| expectations.
| bencoder wrote:
| Having never actually seen the statue of liberty my sense
| when seeing these comparisons is that it's much smaller
| in real life than the version in my imagination - no
| matter how many times I see the comparisons, the statue
| remains much bigger in my head
| titzer wrote:
| These are subjective things, sure. My personal feeling
| upon seeing the shuttle was that it was not that big,
| because I've seen big airliners all my life. I was
| _expecting_ the shuttle to be bigger. So when I looked at
| the parent 's infographic and saw a _737_ and the Statue
| of Liberty there, they didn 't seem right (I've also seen
| the SoL in-person). So the size comparisons I think are
| quite misleading in that graphic, and yeah, I was
| surprised how much smaller the shuttle is than what I
| expected.
| heffay wrote:
| Reminds me of a video I came across last year about about
| landing the space shuttle and the complexities of it all.
| https://www.youtube.com/watch?v=Jb4prVsXkZU
| samstave wrote:
| May I please subscribe to the raw images of ANY space
| telescope...
|
| I mean * _WE*_ /paid/ for them... I would like to access the
| data provided in real-time.
|
| Where can one get the raw images?
| NikolaeVarius wrote:
| > I would like to access the data provided in real-time.
|
| Telemetry is unencrypted. You have access to the data in real
| time. Have fun getting useful data out of it.
|
| > Where can one get the raw images?
|
| Online ,its all public. You might need a pHD to figure out
| how to make it useful to the mark 1 eyeball
| samstave wrote:
| I loved "Mark I Eyeball"
| throwaway946513 wrote:
| I tinkered around with the idea of building an app that would
| get daily images from the space telescopes and the Mars
| rovers, as it turns out - NASA has an API dedicated to them
| (search for it, really easy to find via your favorite search
| engine).
|
| I never ended up building anything from it quite yet (maybe
| soon), but the possibility is there, and the data is free to
| obtain. You have to register for an API key, but again, it's
| still free. The photos are updated quite frequently if I
| remember correctly.
|
| Same thing can be said about the National Weather Service.
| You can get your weather forecasts in nice JSON formats from
| NOAA, all whilst not having to sell your data to The Weather
| Channel, or whatever alternatives exist for weather apps on
| Android.
| perardi wrote:
| As noted elsewhere: um, yeah, all the data is available, for
| free.
|
| But in regards to the James Webb: I don't think you're going
| to find the raw images to be particularly compelling. It is
| imaging in the infrared spectrum. So it's going to require a
| fair bit of processing to get a reasonable monochrome image
| out of that data.
| tonmoy wrote:
| These images would not be your typical jpg taken in the
| visible part of the spectrum. I'm not sure it is cost
| effective to host these image data for random people to
| download without any post processing. If you are dedicated
| enough to understand and post process the data yourself you
| can probably get access to the data for free
| JaimeThompson wrote:
| Give https://api.nasa.gov/ a look.
| ceejayoz wrote:
| Once they're taking images, you'll have access to them.
|
| Hubble's all went up (in raw as well as processed form) at
| https://hla.stsci.edu/, http://hst.esac.esa.int/ehst/, and
| several other places. Expect the same for JWST.
|
| (Same for any other NASA mission. Here's the Curiosity rover:
| https://mars.nasa.gov/msl/multimedia/raw-images/)
| spookthesunset wrote:
| > Once they're taking images, you'll have access to them.
|
| What you say is true but with an asterisk. They grant time
| limited exclusive access to the data to whatever science
| team is using the telescope. It's basically an embargo
| agreement. That way the science team gets the first chance
| to do their research and publish it. Not all missions fall
| under this and in some cases you'll see what is going on
| right away. Eventually all data will become public.
|
| I'll just quote their policy[1]: Access
| to science data from most active missions is often limited
| to the Program Investigator Team during a period of
| exclusive access immediately following the observations.
| The duration of the exclusive access period ranges from a
| few months to as much as a year, depending upon the
| mission, the program category, and other factors. Some
| other data, such as those obtained during facility
| commissioning, or those that are found to duplicate
| concurrent observations by a Guaranteed Time Observer
| (GTO), may also be embargoed for a period of time. Data
| falling under exclusive access can be discovered via MAST
| public interfaces, but may not be retrieved except by
| authorized and authenticated persons. Following the
| expiration of the applicable exclusive access period,
| science data become available for public use without
| restriction.
|
| There is a ton more [2] about how to apply to get time on
| the telescope. Dudes even have a standalone desktop
| application to help put together the proposal.
| [1] https://archive.stsci.edu/publishing/data-use
| [2] https://jwst-docs.stsci.edu/jwst-opportunities-and-
| policies
| dr_orpheus wrote:
| I'm trying to find an article with the exact story, but during
| the building of some of the early large satellites (something
| like the MilStar satellites [0][1]) they realized it would be
| really handy to be to rotate the satellite to work on it from
| different angles. So the satellite manufacturers repurposed
| rotary train car dumpers [2] in order to rotate the giant
| satellites.
|
| [0] https://external-
| content.duckduckgo.com/iu/?u=http%3A%2F%2Fc...
|
| [1] https://en.wikipedia.org/wiki/Milstar
|
| [2] https://en.wikipedia.org/wiki/Rotary_car_dumper
| amelius wrote:
| Did you ever see images like these?
|
| https://www1.udel.edu/udaily/2009/may/cool051509.html
|
| Then it should not be surprising that a telescope is about that
| size.
| theandrewbailey wrote:
| That animation seems right. Hubble space telescope is about the
| size and shape of a bus.
|
| https://www.nasa.gov/audience/forstudents/k-4/stories/nasa-k...
|
| https://www.sciencefocus.com/space/hubble-space-telescope-ho...
| walrus01 wrote:
| The largest geostationary telecom satellites are also quite
| huge, if you were to stand next to one. In the range of 6500 kg
| weight and about the size of a school bus.
| zionic wrote:
| Really sad that 30 years later we're only slightly larger. This
| is a major problem for telescopes since there are hard physical
| limits on resolution vs size.
| jon_richards wrote:
| Obviously it's sad that we don't have a larger Hubble-
| equivalent by now, but the Webb's operating temperature makes
| it a completely different beast. It is massively expanding
| our capabilities in a way a larger Hubble wouldn't. And I'm
| hopeful for the mid-term future, as the massive improvements
| in launch capability we're seeing start to pay off.
| p1mrx wrote:
| SpaceX Starship may help with that, assuming it works as
| intended.
| zelos wrote:
| It's 2.5 times the mirror diameter, which is 6.25 times the
| light collecting area.
| jxcl wrote:
| They both look like they might be similar sizes in an
| illustration like that, but the Hubble mirror is 2.4 meters,
| whereas the JWST mirror is 6.5 meters, which has 7 times the
| light-gathering capability of Hubble.
| Sharlin wrote:
| It's really easy to get a wrong intuitive sense of the size of
| these things! I don't understand why space agencies don't
| always have human figures for reference in their
| visualizations. Or even a simple scale bar! We just get these
| silly "the size of a tennis court" type textual comparisons.
| Few people realize how big the Curiosity and Perseverance
| rovers are, as another example.
| divbzero wrote:
| > _Few people realize how big the Curiosity and Perseverance
| rovers are_
|
| ... and how much larger they are than Sojourner from the
| Pathfinder mission. Perseverance was sent with a metal plate
| depicting profiles of all five Mars rovers to date:
| Sojourner, Spirit, Opportunity, Curiosity, and Perseverance.
| [1].
|
| [1]: https://spaceplace.nasa.gov/mars-rovers/en/mars-
| rovers_metal...
| aksss wrote:
| I believe the banana is the Internet standard for visual
| scale.
| jl6 wrote:
| Also radioactivity, which also suits a Mars rover
| comparison.
| egeozcan wrote:
| > Few people realize how big the Curiosity and Perseverance
| rovers are
|
| To be fair, Perseverance looks as big as I imagined it would
| be, about the size of an SUV but wider (because even in
| 2020s, they still don't have streets in mars, what a bummer):
| https://www.nytimes.com/2020/03/05/science/mars-2020-rover-n.
| ..
|
| Or did my googling fail me? :)
|
| edit: direct image link around paywall: https://static01.nyt.
| com/images/2020/02/18/science/18mars202...
| etskinner wrote:
| https://archive.is/tpcRK for the article
| ravi-delia wrote:
| My mental image until I looked it up was around the size of
| a dog. No, I don't know why
| Angostura wrote:
| Because it's called rover? :)
| jpindar wrote:
| The older ones were smaller.
|
| https://earthlymission.com/size-comparison-generations-
| mars-...
| Sharlin wrote:
| But even Spirit and Oppy were... well, I guess they're
| roughly the size of a _very large_ dog. At 185 kg, much
| heavier than even the largest dogs though.
| [deleted]
| aitchnyu wrote:
| Stupid me thought its go kart sized like the one Howard
| Wolowitz in The Big Bang Theory brought to a baseball
| stadium.
| [deleted]
| sgt101 wrote:
| The JWST at 6.5m is larger than the largest terrestrial
| telescope in my childhood.
|
| Keck was the first one bigger - 1989.
|
| The next one Keck 2 was 1997.
|
| https://en.wikipedia.org/wiki/List_of_largest_optical_reflec...
| sp332 wrote:
| I think most satellites just unfurl solar panels. This one had
| to wrap up the big sun shield as well, and the lens pieces were
| kinda crammed together and then spaced out after deployment
| too. So the rocket couldn't fit something nearly as large as
| this as a payload going up.
| ademup wrote:
| I marvel at how small they are. Why not add 20, 100, or 1000
| more mirrors to JWT? Or launch 10 more of these and go full
| interferometry? Maybe I've just been playing to much Dyson
| Sphere Program, but it feels to me that NASA et al are
| committing the cardinal sin of making the production loop too
| small.
| gunsle wrote:
| Probably because this project has been in development for
| decades and overran it's timelines and budgets multiple times
| (to my knowledge). Congress already hates funding NASA, can't
| imagine they were lining up to give them more money when I'm
| sure they had been asking when's this thing even gonna come
| out?
|
| Also, FWIW, this thing has 100+ points of failure along its
| route to being fully deployed and getting to the L2 spot. A
| lot of people thought for sure at least one area would
| malfunction, would have easily doomed the whole launch. After
| this successful launch, it's possible we'll see discussion on
| building another in this design, but there is already a
| telescope in the planning stages for a 2027 launch, as well
| as four other concepts being developed for the future.
|
| https://en.m.wikipedia.org/wiki/Nancy_Grace_Roman_Space_Tele.
| ..
|
| https://space.stackexchange.com/questions/57407/are-they-
| alr...
| wolverine876 wrote:
| > Congress already hates funding NASA
|
| ? They seem to fund it quite a bit, for generations.
| readthenotes1 wrote:
| The human is not to scale if that's the Webb telescope.
| _joel wrote:
| It definitely is. 6.5m diameter of _the mirror only_ on JSWT
| and 2.4 of Hubble.
| sandworm101 wrote:
| I think the height is there, but the human seems otherwise
| out of proportion. He seems to wide, which gives the illusion
| that he is shorter. And his head is too big, which again
| makes him look younger/smaller, more cartoonish. I think this
| is from a stock cartoon character rather than a real person.
| danbruc wrote:
| I measured the mirror - top to bottom - as 304 pixels and the
| human as 86 pixels. This makes the human 1.83 meters given a
| mirror diameter of 6.5 meters. So it is to scale.
| anon_123g987 wrote:
| A human standing next to a full-size replica:
| https://external-
| content.duckduckgo.com/iu/?u=https%3A%2F%2F...
|
| It looks the same to me.
| pseudolus wrote:
| Where is this replica located? Is it open to the public?
| asoneth wrote:
| I recall seeing a full-sized mockup of the James Webb at
| the South by Southwest about ten years ago. It was
| accompanied by a small traveling exhibit about the
| mission and some folks from a NASA (or Northrup?)
| education team to answer questions. They had been taking
| it to cities and museums across the country.
|
| Not sure where it is now or if there are multiple full-
| sized mockups, but I wouldn't be surprised if one ends up
| in the public collection at Udvar-Hazy Smithsonian Annex
| where many big NASA toys end up.
| anon_123g987 wrote:
| I don't know where it is currently, but according to this
| 2008 article it was on a world tour at that time.
|
| https://phys.org/news/2008-07-james-webb-space-telescope-
| ful...
| lolive wrote:
| Maybe that video can also help:
|
| https://svs.gsfc.nasa.gov/10776
| bestouff wrote:
| It's funny how the excellent job of the French Ariane launcher is
| nowhere to be seen in this (and others) article.
| irrational wrote:
| I've seen it mentioned tons of times in articles. Especially in
| regards to how well it did which which leads to fuel savings
| which leads to a longer life.
| jamincan wrote:
| Shortly after launch there were quite a few articles talking
| about how well the launch went on the Ariane and how that
| allowed the mission to be extended to 20 years or so.
|
| I'm not sure who it was anymore (possibly Scott Manley on
| youtube), but apparently ESA had been setting aside the
| components for the Ariane 5 that tested best to be used for the
| launch of JWST to lower the risk of failure and that might
| explain in part why it was able to launch it so precisely - it
| was not your average Joe's Ariane 5.
| isolli wrote:
| I also heard that for this launch, Arianespace made sure to
| make no innovation whatsoever to the launcher (usually each
| launch is used to test small improvements).
|
| Source: podcast in French
| kortex wrote:
| So they essentially binned the rocket parts much the same way
| a chip fab would?
| PetitPrince wrote:
| They selected the parts that were the most up to spec (not
| necessarily the strongest, but the most faithful to spec).
| NikolaeVarius wrote:
| No? This is a completely meaningless comparison
| [deleted]
| jacobolus wrote:
| It's the same idea. Instead of making a tighter spec and
| spending more resources making just the right number of
| parts meeting the specified tight tolerance, use a looser
| production tolerance and make a bunch of parts, and then
| (for an especially tricky use case) pick the parts
| satisfying a tighter tolerance after production, leaving
| the remaining parts for less demanding jobs.
| js8 wrote:
| Worse, journalists often compare Webb with Hubble, but they
| mostly ignore the
| https://en.wikipedia.org/wiki/Herschel_Space_Observatory, which
| had a larger primary mirror (for example, https://webb.nasa.gov
| /content/observatory/ote/mirrors/index....). It's a very subtle
| form of American exceptionalism.
| Steltek wrote:
| Maybe because Herschel was active for only a few years while
| Hubble is still going? Hubble has also produced some of the
| most recognizable images of space. It's clearly a name with
| more awareness in the general public.
| CrazyStat wrote:
| I'm not sure it's American exceptionalism, just that Hubble
| has been around a long time and is much more prominent in the
| public conscience thanks to iconic images like the Hubble
| deep field.
|
| If someone builds a big new ocean liner you know journalists
| are going to compare it to the Titanic. Same thing.
| dev_tty01 wrote:
| Yes, Herschel was a great project by the ESA. It certainly
| got short shrift within the US press despite significant
| contributions from NASA and JPL. I hope it got plenty of love
| from the European press. Great work.
| justin66 wrote:
| > It's a very subtle form of American exceptionalism.
|
| Oh, bullshit. NASA spends an awful lot of money and effort on
| promoting its projects to the English-language press. Does
| the ESA make a comparable amount of effort?
| js8 wrote:
| I am not sure where we disagree. I am talking about the
| (false) perception that the U.S. is the #1 among world
| nations. Maybe it is caused by comparatively higher
| marketing budget, but that doesn't ultimately matter,
| because the point is, the perception is still false, and
| ignoring Webb's predecessor contributes to it.
|
| OTOH, I think Webb is amazing, and fairly, perhaps without
| the marketing it wouldn't even exist because of all the
| American deficit hawks.
| justin66 wrote:
| > the (false) perception that the U.S. is the #1 among
| world nations
|
| The #1 what? I wouldn't blame you for using some unkind
| phrases here, and I suspect you want to! But it's
| certainly not false that the U.S. does much more space
| exploration than any other nation, spends a lot more on
| it, achieves more in space, etc. None of that invalidates
| the work of other nations, and spaceflight and the
| production of scientific data seems like a very healthy
| form of competition (and cooperation!) between nations.
| If the U.S. isn't #1, I am curious how you are keeping
| score.
|
| Herschel didn't just get less English-language press than
| American made space telescopes. It was less prominent in
| the public consciousness than short, much less expensive
| Japanese missions like Hayabusa and Hayabusa2. I doubt
| any of this is about American exceptionalism.
| spookthesunset wrote:
| > OTOH, I think Webb is amazing, and fairly, perhaps
| without the marketing it wouldn't even exist because of
| all the American deficit hawks.
|
| It's just like everything else in life. You can build the
| best product in the world but it won't make a damn bit of
| impact on people's lives unless you let them know it
| exists. Marketing your product is just as important to
| its success as the product itself.
| slim wrote:
| Ariane 5 was cool in 1995
| ragebol wrote:
| And now too, since it ~doubled the science/dollar output of
| the telescope by doubling the lifetime. I think that's cool
| arcticfox wrote:
| "doubled" the lower bound on what was surely an extremely
| conservative estimate meant to avoid a perception of
| failure if things didn't go perfectly. The Opportunity
| rover had a "90-day" expected lifetime and lived until 15
| years old. It's great that Ariane performed superbly but
| this "doubling" calculation is pretty silly.
| mrtksn wrote:
| > The Opportunity rover had a "90-day" expected lifetime
| and lived until 15 years old. It's great that Ariane
| performed superbly but this "doubling" calculation is
| pretty silly.
|
| Yeah, no. JWST has a limited lifetime because of the
| finite fuel, that's completely different from building a
| machine for a purpose and the machine not falling apart
| at the end of the initial mission.
|
| When people say Ariane doubled the lifetime of JWST, they
| mean Ariane performed much better than the allowed
| margins, thus pushing the fuel efficiency to its limits.
|
| Think this, a Toyota has a lifetime of 100K miles but
| many get 200K out of it. That's completely different from
| achieving 80mpg on a car rated 40mpg.
|
| When someone tells you that they are driving so precisely
| that they are getting twice the milage, is it appropriate
| to say "So what, my car was supposed to last 100K miles
| but lasted 200K"?
|
| I think, no.
| 1125spacex wrote:
| titzer wrote:
| It's amazing that they pulled this off without node and
| electron, you mean?
| abhiminator wrote:
| Ars Technica did a well-written story on it recently --
| https://arstechnica.com/science/2022/01/all-hail-the-ariane-...
| ur-whale wrote:
| > It's funny how the excellent job of the French Ariane
| launcher is nowhere to be seen in this (and others) article.
|
| US ego is already badly bruised that they've had to launch this
| highly visible project on a foreign rocket, and now you'd want
| them to sing the frenchies praises?
|
| That's a huge ask.
| macintux wrote:
| It got a lot of good press at the time, but agreed, it warrants
| a mention.
| tunap wrote:
| That is an interesting observation I never considered. If it
| were a SpaceX rocket, it would have been mentioned once per
| paragraph, minimum.
| arcticfox wrote:
| If it was a SpaceX rocket, it would be getting ready to fly
| again. Expendable rockets have been putting up payloads for
| 60 years at this point, SpaceX has been flying reusable
| rockets for less than a decade.
| jvanderbot wrote:
| This is absolutely true but entirely uninformative in this
| context. It's also a bit hilarious as it reinforces GP's
| suggestion that you can't involve or invoke SpaceX without
| a breathless-sounding shower of accolades stealing the show
| from the main payload / mission.
| raverbashing wrote:
| Not necessarily. Larger payloads (and maybe some
| trajectories) forego the reusability of the rocket (even
| Falcon Heavy)
| arcticfox wrote:
| Good point, but it's one major reason why SpaceX makes
| the news (also Crew Dragon) and Arianespace doesn't, even
| if it doesn't apply in every instance.
|
| If SpaceX was simply doing the same thing as everyone
| else has for 60 yrs, no one would care, I don't
| understand why people think they're the same thing
| wolverine876 wrote:
| You don't think it has something to do with Elon Musk's
| self-promotion and large cult? Quick, who is the CEO of
| Arianespace? Who is heading up the SLS project?
| Dave3of5 wrote:
| Actually Hubble was put into space by a (mostly) reusable
| system the space shuttle STS-31. That was about 30 years
| ago.
| NikolaeVarius wrote:
| The Space Shuttle was refurbishable. Its barely a valid
| comparison
| nexuist wrote:
| Calling the Space Shuttle "mostly reusable" is laughable.
| It cost 1.5 billion dollars _per launch_ [1] whereas a
| reused Falcon 9 costs 50 million to launch.
|
| [1] https://en.wikipedia.org/wiki/Criticism_of_the_Space_
| Shuttle... [2] https://en.wikipedia.org/wiki/Falcon_9
| jedberg wrote:
| The shuttle could cary 29,000kg to orbit, the Falcon 9
| can only carry 22,000kg (30% more capacity) plus 8
| astronauts (Falcon can only carry 3), and was designed
| and built in the 70s.
|
| So yeah the Falcon is an improvement and I'm sure will be
| better one day, but the Space Shuttle was a huge
| achievement for its time, and as of today there is no
| lift system that can match it for both capacity and
| reusability.
| cecilpl2 wrote:
| Slight nitpick - Crew Dragon currently carries 4 crew
| members and there's no particular reason it couldn't
| carry more (ie the rocket could handle it).
| pfdietz wrote:
| At no point in the history of the Shuttle program would
| it have been a mistake to shut it down. By any metric,
| I'd call it a failure.
| Steltek wrote:
| I don't get the need to bag on the Shuttle program here.
| The Shuttle was designed nearly 50 years ago with
| drastically different requirements and stakeholders.
| pfdietz wrote:
| It's because people still defend it, or imply it was more
| worthy than it actually was. And because the same mistake
| is being repeated right now (SLS).
| mulmen wrote:
| SLS isn't the currently-in-development spacecraft that
| utilizes hundreds of ceramic tiles to aerobrake through
| the atmosphere. SLS is basically a modern Saturn V. A
| complete departure from the Shuttle, with the exception
| of-re-using the SRB design. On paper a very conservative
| choice.
|
| Starship looks a lot like Shuttle 2.0 to me. Except the
| landing is somehow even more terrifying.
|
| As far as I can tell the idea with Starship is to design
| a vehicle that can survive losing a few tiles because
| that's inevitable.
| pfdietz wrote:
| The point of SLS is that it's a politically motivated
| boondoggle. This is also what the shuttle was. Nixon ok-
| ed it not because it was a good idea, but because of
| aerospace votes in California.
| wolverine876 wrote:
| What is that based on?
| signatoremo wrote:
| This is one, among others, right after it was announced. Maybe
| you don't follow space news as closely as you think you do?
|
| https://arstechnica.com/science/2022/01/all-hail-the-ariane-...
| mnw21cam wrote:
| If you go to
| https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html then
| there are repeated statements about how the rocket did such a
| good accurate job launching Webb onto its intended trajectory
| that the telescope hasn't had to use as much of its own rocket
| fuel as they expected, so the fuel is now expected to last 20
| years instead of 10.
| _ph_ wrote:
| I am quite relieved that all the deployment worked out and so
| looking forward to the first images. I hope, planning for a true
| Hubble successor (a telescope in the visual range) starts soon.
| Maybe a one-off Starship could be the telescope housing, it would
| enable an 8m mirror without any folding, just the tip of the
| Starship would open up once in orbit.
| spookthesunset wrote:
| Why not go for a much larger folding mirror?
| Dave3of5 wrote:
| I know they're not reading HN but well done big congrats to all
| involved.
| junon wrote:
| Huge achievement, I can't wait to see what they find.
| ctdonath wrote:
| Amazing how a few meters of mirror can make out objects billions
| of light-years distant. Yes it's _big_ - insofar as human-built
| telescopes have been - yet is so relatively minuscule per what it
| observes. Having gone from first flight to JWST in such a short
| time is staggering (Wright Bros 120 years ago - I 've been alive
| nearly half that time); how soon will we achieve orders-of-
| magnitude bigger telescopes? say, multiple 100x-wider JWSTs
| operating from multiple LaGrange points? Think big!
| wlesieutre wrote:
| In a slightly different vein, ESA's Gaia mission measured the
| distances to billions of stars by looking at how their position
| shifts as we orbit from one side of the sun to the other. Not
| taking highly detailed images like JWST, but in some ways you
| can think of it as a telescope the size of Earth's orbit.
|
| https://www.esa.int/Science_Exploration/Space_Science/Gaia/P...
|
| https://skyandtelescope.org/astronomy-news/gaia-makes-most-a...
| craigharley wrote:
| How long until my new desktop wallpaper?
| Aachen wrote:
| 6 months
| pwdisswordfish9 wrote:
| Non-cookiewalled link:
|
| https://text.npr.org/1075437484
| sillyquiet wrote:
| I think Destin of the Smarter Every Day YT channel had an
| interview a couple years ago with Dr. John Mather, the senior
| project scientist of the JWST, where he asked something like
| "will you be nervous during the launch and deployments", and Dr.
| Mather replied " I don't get anxious about stuff I can't deal
| with", and that they've tested everything they thought of to
| test.
|
| I was super impressed with Dr. Mather, not only that he seemed so
| wise, but also that this super busy man took the time to do an
| hour long interview with a random You-Tuber. I think the JWST
| project is in good hands.
|
| Edit: I guess Destin is not a 'random' You-tuber, but someone
| that was well-placed to connect with Dr. Mather. Still, he's not
| CNN or BBC - he's a guy with a handheld camera that doesn't ask
| fluff question, but questions intended to help inform himself and
| his audience. Still think Dr. Mather thinking it was important to
| spend so much of his schedule with Destin was impressive.
| cporrast wrote:
| I had the privilege of meeting Dr. Mather 10 years ago, when he
| spent a new years with my family, he booked a vacation with my
| parents company, and he is without a doubt the smartest person
| I have met in my life also very humble and interested.
|
| One of the best experiences of my life.
| leephillips wrote:
| Well, Dr Mather surely had no idea who I was when I was
| researching my article on the JWST, but he was generous with
| his time and thoughts.
|
| https://arstechnica.com/science/2016/03/meet-the-largest-sci...
| Tenemo wrote:
| Destin's channel is one of the older, best-known channels in
| the YT's educational sphere. Recently, the US Navy even let him
| on a multi-day tour of a nuclear submarine and tape classified
| information (later redacted). He himself worked in the
| military. I don't think that it's fair calling him a random
| youtuber, to me he seems like the perfect youtuber to interview
| such people (as Destin himself has a background in rocketry).
| onceiwasthere wrote:
| If I remember right, his dad was/is very involved in the
| JWST.
| Steltek wrote:
| It's really amusing contrasting the brains going around in
| that family with them both goofing off with a lawn mower
| carburetor in the garage.
| loco5niner wrote:
| Funny, I wouldn't use the word contrasting, I thought it
| was cool that their goofing was was around smart stuff.
| (probably just because I didn't know much about how a
| carburetor works, and after watching the video, know much
| more)
| onceiwasthere wrote:
| Very true. Although not such an uncommon contrast in
| Huntsville, AL, where Destin lives.
| Laremere wrote:
| Destin has also peaked (or very close to it) in importance of
| person interviewed, as he interviewed Obama during their
| presidency. Though, sadly not an hour long.
| https://youtu.be/GpWQHFzrEqc
| snakeboy wrote:
| Just out of curiosity, is it considered best practice these
| days to use the gender-neutral "their" even with a specific
| subject (Obama) who is known to use masculine pronouns for
| himself?
| awestroke wrote:
| It doesn't matter
| TaylorAlexander wrote:
| As someone tuned in to queer twitter I can say that if
| you know someone's pronouns you should use them, so
| ideally for Obama you would use he/him. But also we're
| all using they/them a lot more for people when we're not
| sure and that can bleed in to people even when we do know
| their pronouns, and generally that's not a big deal. Only
| becomes a problem when a trans person has a clear
| preference for she/her or he/him (or anything else) and a
| person repeatedly and willfully uses they/them, as that
| can be used to deny recognition of someone's gender
| identity. But it's generally not a problem if you use
| they/them for a cis person once, that can just slip out.
| We're more sensitive around pronouns for trans people,
| since they are much more likely to have trauma around
| that. They/them is cool for someone with unknown pronouns
| but it's best to politely ask as soon as possible and
| begin to use the preferred ones.
| wolverine876 wrote:
| OT: I use they/their by default, unless I know otherwise,
| but what to do with other common gendered terms such as
| Mr./Ms./Mrs, Sir/Madam/Ma'am/Miss?
|
| These aren't avoidable problems: e.g., in the greeting
| for a business letter ('Dear ...'), or when getting the
| attention of a member of restaurant waitstaff whose name
| I don't know, etc.
|
| Someone needs to come up with a plausible set of gender-
| neutral terms. They/their/them works for
| she/hers/her/he/his/him circumstances, but the needs are
| broader than that.
| frosted-flakes wrote:
| Definitely not.
| Steltek wrote:
| I think it would be nice if English evolved to only
| ungendered pronouns. Eliminates accidental offense while
| also reducing everyone's cognitive load.
|
| Also, you reminded me of a quote from yesterday: "The
| problem with defending the purity of the English language
| is that English is about as pure as a cribhouse whore."
| BurningFrog wrote:
| Persian and Chinese have, if I remember correctly, no
| gendered pronouns.
|
| No effects on gender equality seem observable.
| munificent wrote:
| I don't disagree with you, but I think it's worth
| pointing out that there is a pragmatic benefit to
| gendered pronouns.
|
| You can think of pronouns as sort of like `$?` in bash or
| `_` in Python's interactive shell. They give you a short
| way to refer to a previously mentioned noun. When you
| have more than one of these "special variables", you can
| use them more often as long as they conveniently get
| uniformly distributed across the previously mentioned
| nouns.
|
| So, in English, you can say:
|
| "Blaine Wolfeschlegelsteinhausenbergerdorff Sr. gave
| Rhoshandiatellyneshiaunneveshenk Koyaanisquatsiuth
| Williams a sweater for Christmas. She liked his gift."
|
| The second sentence can use two pronouns because they
| happen to be unambiguous. With only a single pronoun,
| that sentence ends up like:
|
| "Rhoshandiatellyneshiaunneveshenk liked
| Wolfeschlegelsteinhausenbergerdorff's gift."
|
| (This is obviously an extreme example for comedic
| effect.)
|
| This is also why Romance languages have noun gender for
| inanimate objects where actual biological gender isn't
| meaningful. It's not about genitals, it's about
| scattering a few pronouns uniformly across the noun
| space.
|
| Of course, one might rightly argue that gender is not a
| good mechanism to use for your pronoun distribution. We
| could do something like shells do where we assign
| pronouns based on recency of the mentioned noun. Or some
| other system.
|
| But my point is that gendered pronouns aren't completely
| bananas. They serve a pragmatic function.
| billforsternz wrote:
| Interesting rationalisation for gendered inanimate nouns
| in romance languages, thanks. Also used in many/most
| other Germanic (and other language families?) right? Is
| your explanation a personal inspiration or established
| theory? For it to make sense they would need to (for
| example) refer to (say) a table as 'he' later in a
| sentence. Do they do that?
| munificent wrote:
| Definitely not a personal inspiration, but I can't recall
| where I first heard the idea.
|
| _> For it to make sense they would need to (for example)
| refer to (say) a table as 'he' later in a sentence. Do
| they do that?_
|
| I don't speak any Romance languages beyond high school
| Spanish, but I assume that's the case.
| uj8efdkjfdshf wrote:
| IMO grammatical gender in Indo European languages (of
| which the Germanic and Romance language families are a
| part of) reflect how nouns and their references
| (pronouns, adjectives etc) are semantically linked by
| modifying the word endings of the latter to better
| reflect those of the original noun - I like to think of
| it as the equivalent of type suffixes in assembly
| language.
| metalliqaz wrote:
| It costs me absolutely zero cognitive load. You don't
| have to worry about that.
|
| Now, trying to parse out if "they" is meant to refer to a
| group or an individual when used in place of s/he, that
| does take some work.
| loco5niner wrote:
| Politicizing this topic is what causes the cognitive
| load.
| toxican wrote:
| He's also in the middle of a coast guard series he filmed
| last year. Pretty interesting stuff.
| dboshardy wrote:
| > the US Navy even let him on a multi-day tour of a nuclear
| submarine and tape classified information (later redacted)
|
| They _paid_ him to tour it. It was a marketing event for the
| US Navy to drive recruitment.
| sillyquiet wrote:
| They did? I am not disagreeing, just wondering if he
| disclosed that or how you found out.
| mulmen wrote:
| In the first video in the series Destin himself says the
| Navy did not pay him.
|
| https://youtu.be/5d6SEQQbwtU&t=2m47s
|
| I do recall him mentioning his own biases and conflicts of
| interest at some point but I don't recall what series that
| was a part of.
| jermaustin1 wrote:
| Destin is far from a random YTer, he's a former Army Aerospace
| Engineer, worked with NASA if I'm remembering correctly, and
| has a VERY large audience. He would have been able to reach out
| to the right people and get the interview properly, not just
| random cold emailing like a real random YouTuber would.
| belter wrote:
| Its a great interview and starts with his Dad, who also worked
| on the JWST... https://youtu.be/4P8fKd0IVOs
| sylware wrote:
| joshspankit wrote:
| No offence to anyone involved in this genuinely exciting and
| humbling project:
|
| _Please stop putting me on the edge of my seat until we're just
| about to get our first images (many months from now)_
|
| I was excited about the launch, and happy to know it went better
| than expected so that there is extra fuel, but each milestone is
| burning me out. Let me know when the tests are done and we can
| view the images of distant objects.
| stronglikedan wrote:
| Considering the number of times I've literally shed tears of
| joy since launch, I respectfully disagree. Keep those
| milestones coming, baby!
| Maxburn wrote:
| Question; why is the Where is Webb page saying current speed is
| .1255 miles/second? There's a blurb in the explainer that says
| that speed is Earth relative.
|
| https://jwst.nasa.gov/content/webbLaunch/whereIsWebb.html?s=...
| ur-whale wrote:
| I always find mentions of "speed" of spaceships in the press
| very strange: they never specify the reference frame.
| Maxburn wrote:
| Right? Sitting still we are 1,037 mph at the equator. And
| then you can consider relative to our sun, or galactic core,
| etc. https://www.space.com/33527-how-fast-is-earth-
| moving.html
| omnicognate wrote:
| It's in orbit round L2, not stationary relative to Earth.
|
| Video as linked by another comment:
| https://www.youtube.com/watch?v=6cUe4oMk69E&list=TLGG8tIphgp...
| Maxburn wrote:
| Watching that video it seems to me relative to earth the
| speed is Zero? Distance to the earth is not changing.
| Relative to other things sure it's moving around.
| a_code wrote:
| I have a dumb question. If the telescope is always moving in an
| orbit around L2 and then also around sun, how does it focus at a
| single area for long durations ?
| GlenTheMachine wrote:
| Two parts to this answer. The short one is that this amount of
| orbital motion results in very very small differences in angle
| given the very long distance of the objects it's focused on and
| the relatively short exposure times (short with respect to the
| orbital period of the telescope).
|
| The somewhat longer answer is that the spacecraft establishes
| an orientation using its Control Moment Gyros (CMGs). The ops
| team _could_ use the CMGs to maintain pointing if this small
| amount of image smear ever became significant. But the CMGs
| would probably induce as much image smear as they removed,
| since they will induce structural vibrations in the spacecraft,
| so the utility of this approach would be questionable.
| a_code wrote:
| Thank you !
| EMM_386 wrote:
| This was an absurdly teeth-clenching deployment.
|
| And no back-up, even if the Ariane launch failed. No back-up.
|
| Congrats to everyone across the board for getting this amazing
| telescope right where it needs to be.
|
| Now all we need is the mirror alignment and we're in for some
| seriously incredible science.
| s5300 wrote:
| It's really sad to think about how well NASA works when you
| consider how little funding they get and how hard they have to
| fight for it. It's honestly quite ridiculous.
|
| I know a lot of military industrial complex boils down to being
| nationwide jobs programs, e.g. everything to do with the F-35.
| But NASA? I don't think they're anywhere near as close to being
| a "jobs program"
|
| Off the top of my head, I really can't think of many things
| NASA as a whole has fucked up.
|
| Challenger & Columbia. Challenger wasn't a NASA problem, it was
| a Politicians & Bureaucracy problem. As I earlier mentioned...
| the people responsible for my initial statement of "how well
| NASA works" knew that disaster was highly likely with
| Challenger launch. But bureaucracy didn't care. Haven't read
| into Columbia so won't comment.
|
| So why the hell do they get so little funding... it's
| depressing to think about. My cynicism doesn't think James Webb
| success is going to bring in much more funding. SpaceX,
| understandably, is likely going to take more & more space
| related contracts.
|
| I still think NASA deserves much, much better treatment.
| justin66 wrote:
| NASA certainly has their share of "jobs programs." The SLS is
| a prime example. Not NASA's fault: when congress gives you
| money and tells you to work on something, you work on it.
|
| https://en.wikipedia.org/wiki/Space_Launch_System
|
| > I still think NASA deserves much, much better treatment.
|
| This is certainly true.
| Rebelgecko wrote:
| This may or may not help your cynicism, but here's 2 fun
| facts:
|
| * NASA doesn't even get the majority of the US government's
| space spending
|
| * NASA's budget is still larger than every other country's
| civilian space program _combined_
| neatze wrote:
| What are you talking about Webb was build by contracting
| defense contractors, like for example Northrop Grumman
| (primary contractor if not mistaken) and Lockheed Martin who
| also build F-35, there is YouTube video where Lockheed does
| presentation about Webb telescope project complexity.
| mturmon wrote:
| It's true that Northrop Grumman was the prime contractor.
| You don't want to keep all the skills to build this, and
| all the manufacturing steps, in-house.
|
| But the project leadership and key pieces of the design
| were at GSFC and JPL.
|
| Full list:
| https://webb.nasa.gov/content/meetTheTeam/team.html
| GlenTheMachine wrote:
| Every large project is built by multiple partners. But in
| this case, the overall _design_ and systems engineering was
| done by NASA /Goddard. Claiming otherwise is like saying
| that Foxconn makes iPads, not Apple.
| newaccount2021 wrote:
| chernevik wrote:
| It seems to me that there are two NASAs: The unmanned
| exploration programs, which do amazing things, and the manned
| exploration programs, which look very much like jobs
| programs.
|
| I'm not an expert, but I haven't yet seen a good science
| rationale for returning to the moon. I'm not aware of what
| we've learned from the International Space Station. And the
| Space Shuttle was an expensive and needless boondoggle that
| killed fourteen people for no good reason. If someone can
| correct me on the science we gain from these programs I'd
| welcome it. Because it seems to me that we get precious
| little science from the treasure and blood dedicated to these
| programs.
|
| The Apollo missions were a different thing, they taught a lot
| about the Moon and brought back crucial material like the
| Genesis Rock.
|
| On the other hand the unmanned program does amazing things
| like Hubble, Voyager, Magellan, the Mars probes, and on and
| on. And soon, Webb. These have told us amazing things about
| our world, and we should be doing more of them.
| spookthesunset wrote:
| > I'm not aware of what we've learned from the
| International Space Station
|
| If you watch videos of the people on the space station you
| begin to be reminded of "remote hands" in a data center.
| The space station is like a colo-facility that houses
| science experiments instead of racks of computers. The
| people on board seem to exist as "remote hands" that
| maintain those science experiments for whatever science
| team is on the ground running them.
|
| This is all conjecture, of course... but I've watched
| enough of "Hi I'm somebody on the space station, let's walk
| around" videos to draw this opinion. The ISS is a science
| lab that orbits the earth. The people on board are there to
| be remote hands.
| ativzzz wrote:
| Have there been any interesting breakthroughs or findings
| from the science done aboard the ISS?
| btkramer9 wrote:
| I know you're asking specifically about results from on
| board the ISS but here's something more broad
| https://en.wikipedia.org/wiki/NASA_spinoff_technologies
| mulmen wrote:
| > I'm not aware of what we've learned from the
| International Space Station.
|
| We learned about the effects of microgravity on the human
| body for one. Useful for future trips to the Moon and/or
| Mars.
|
| Plus we've had the benefit of a microgravity laboratory
| staffed by world class scientists for two decades.
|
| Putting people back on the Moon is valuable just as a
| technology demonstration and test for more ambitious
| missions like Mars.
|
| As you say, Apollo taught us a lot about the Moon. But it
| didn't teach us _everything_. So if Apollo taught us
| something then clearly there is value in sending humans.
|
| > And the Space Shuttle was an expensive and needless
| boondoggle that killed fourteen people for no good reason.
|
| Without the Shuttle there is no ISS. So any benefit gained
| from the ISS is owed at least in part to the Shuttle.
| dev_tty01 wrote:
| I agree with your overall sentiment, but I have to disagree
| with this:
|
| >Challenger & Columbia. Challenger wasn't a NASA problem, it
| was a Politicians & Bureaucracy problem.
|
| NASA managers overrode the recommendations of the engineers.
| That was absolutely a NASA problem. Sure they were under some
| political pressure, but they made the wrong call in the face
| of strong data. Columbia too was a management priorities
| problem.
|
| That being said, NASA is doing great science. NASA is
| compromised of humans so they are therefore imperfect, but I
| would also love to see them get more support. Their $23
| billion dollar budget is only 3% of the size of the DOD
| budget.
|
| As far as SpaceX, they are a NASA subcontractor, executing
| goals specified by NASA. I don't understand your concern.
| (SpaceX also has a thriving private satellite business of
| course.) The entire Apollo program was executed by NASA paid
| subcontractors. That is how NASA operates. Their primary role
| is to spec, subcontract, and manage. SpaceX is doing things
| for less money than other subcontractors, so they are helping
| NASA's budget.
| 2457013579 wrote:
| Parent comment: > It's really sad to think about how well
| NASA works when you consider how little funding they get
| and how hard they have to fight for it. It's honestly quite
| ridiculous.
|
| Sibling comment (dmd): > I saw a study a few years ago
| where people were asked how much funding various agencies
| get, and the majority of people thought NASA was more than
| 10% of the federal budget; some even went as high as 25%.
| (It's less than half of 1%.)
|
| Your comment: > [NASA's] $23 billion dollar budget is only
| 3% of the size of the DOD budget.
|
| NASA's budget is about half a percent of total DoD budget,
| but that doesn't tell an accurate story. Most people assume
| NASA is synonymous with the total or almost total US space
| budget, but its less than half. You can do the math in 2022
| if you would like [0], but in 2013 NASA's budget was $16.8B
| [1], and the total space budget was $39.3B [2]. According
| to that article, in 2013 every other nation was supposedly
| under a $10B space budget [2], but can't really speak to
| the validity of that. I think it's reasonable to say we
| spend a decent amount on space compared to others. All that
| said, not opposed to an increased space budget, more space
| is good in my book.
|
| [0] https://comptroller.defense.gov/Portals/45/Documents/de
| fbudg...
|
| [1] https://en.m.wikipedia.org/wiki/Budget_of_NASA
|
| [2] https://www.weforum.org/agenda/2016/01/which-countries-
| spend...
| dev_tty01 wrote:
| Thanks for the comment. Your reference [1] shows that
| NASA's budget is typically 0.5% of the total Federal
| budget in recent years, not the DOD budget. In 2020, NASA
| was about 23 billion and the DOD was about 766 billion,
| or about 3%. As to your other point, yes, some of the DOD
| budget is spent on space. That number will continue to
| increase.
|
| Interesting tidbit: In constant 2020 dollars, peak NASA
| spending during Apollo was only twice today's budget.
|
| https://en.m.wikipedia.org/wiki/Budget_of_NASA
| https://www.statista.com/statistics/264494/nasas-budget/
| https://www.statista.com/statistics/272473/us-military-
| spend...
|
| *The third link says 2012, but it covers through 2020.
| voidmain0001 wrote:
| ...NASA is compromised [comprised/composed entirely] of
| humans...
| dev_tty01 wrote:
| Oops. Thanks. Yes, I meant comprised, although I suppose
| humans also lead to compromise...
| dmd wrote:
| I saw a study a few years ago where people were asked how
| much funding various agencies get, and the majority of people
| thought NASA was more than 10% of the federal budget; some
| even went as high as 25%. (It's less than half of 1%.)
| scrumbledober wrote:
| definitely not as much of a jobs program, considering
| probably anyone smart enough and hard working enough to get a
| job at NASA could get a much easier and more high paying job
| elsewhere.
| ur-whale wrote:
| > It's really sad to think about how well NASA works when you
| consider how little funding they get and how hard they have
| to fight for it.
|
| I do agree with you, but have you maybe considered that
| you're looking at it the wrong way?
|
| Isn't there a saying that armies that eat bad food win more
| battles?
|
| Could it be that because NASA is not funded at the level they
| deserve, they have to be more efficient?
| mulmen wrote:
| By the same logic we could conclude that the US Military is
| an efficient operation. After all I can find someone who
| will argue their funding needs to be increased.
| mabbo wrote:
| Mirror alignment was done in the days leading up to insertion,
| wasn't it?
|
| Afaik, all that's left is testing and cooling- the cold side is
| still around 63K and needs to get down to 50K (-223C).
| entrep wrote:
| Mirror deployment was done before insertion, moving the 18
| mirrors up from their locked position by 12.5 mm. Now, 3
| months of mirror alignment will follow. They will align with
| a reference star having to first move one mirror a little bit
| to identify how the mirror affects the alignment, then
| calculate the alignment and move the mirror. Each mirror's
| position can be controlled at 10 nm resolution.
| jacquesm wrote:
| It's not only position, also deformation by pulling or
| pushing on the center of the mirror changing it's
| curvature.
| entrep wrote:
| Correct. And since the beryllium mirrors are 8 times
| harder than steel, it's probably a tough job.
| jacquesm wrote:
| Not really. They are quite thin and the deformation is
| minute, on the order of less than a micron at the largest
| point.
| dimator wrote:
| I can't fathom how they have a servo, a linear actuator,
| or anything else, that can apply pressure to the mirror
| and keep it there, for _years_ , in the most extreme
| environments.
|
| Every component of this thing is mind bending.
| schiffern wrote:
| " _Cryogenic Nano-Actuator for JWST_ " https://www.esmats
| .eu/amspapers/pastpapers/pdfs/2006/warden....
| jacquesm wrote:
| Electromagnet with a constant current running through it
| would do the job nicely I would think? Keep in mind that
| with the sun always shining where Webb is that power is
| not really their first constraint.
| Elsewhere-16-62 wrote:
| JWST will hear "GOD" Laughing (The Big Laugh).
| itazula wrote:
| This animation,
| https://www.youtube.com/watch?v=6cUe4oMk69E&list=TLGG8tIphgp...
| is a nice visualization of the L2 orbit. It was different than
| what I expected.
| WithinReason wrote:
| For some reason I expected it to stay in Earth's shadow. L2 is
| probably too far from Earth for that.
| justin66 wrote:
| An object at L2 absolutely could avoid the sun and stay in
| Earth's shadow. It would be problematical for this
| spacecraft, which is powered by a solar array.
| willis936 wrote:
| Earth's umbra doesn't reach L2.
|
| https://en.wikipedia.org/wiki/Umbra,_penumbra_and_antumbra
|
| https://astronomy.stackexchange.com/questions/13585/does-
| ear...
| justin66 wrote:
| Ah, that stack exchange comment is super interesting.
|
| "If Earth would be 9% larger in diameter, but with the
| same mass, its umbra would end almost exactly at L2."
| bgirard wrote:
| I did some research here to understand this better:
| https://webb.nasa.gov/content/about/orbit.html
|
| > This [L2] orbit (which takes Webb about 6 months to
| complete once) keeps the telescope out of the shadows of
| both the Earth and Moon.
|
| >What is special about this orbit is that it lets the
| telescope stay in line with the Earth as it moves around
| the Sun.
|
| and
|
| > Webb's position out at L2 also makes it easy for us to
| talk to it. Since it will always be at the same location
| relative to Earth-in the midnight sky about 1.5 million
| km away - we can have continuous communications with it
| as the Earth rotates through the Deep Space Network (DSN)
| willis936 wrote:
| As did I.
|
| https://news.ycombinator.com/item?id=29859522
| adgjlsfhk1 wrote:
| They specifically avoid earth's shadow because they use solar
| panels (by shadow here, I mean penumbra, they're too far away
| to be in total shadow).
| wolverine876 wrote:
| I've been wondering about that same issue and someone
| suggested that as a possibility. Do you know where NASA
| actually states it?
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