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James Webb telescope reaches its final destination in space, million miles away

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Re: James Webb telescope reaches its final destination in space, million miles away

#101

Post by dharmab »

wongarsu wrote: post #78
amelius wrote: post #73

Earlier quoted context omitted.

Russians had the Buran, with more or less the same dimensions. https://en.wikipedia.org/wiki/Buran_(spacecraft)

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.

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.

Re: James Webb telescope reaches its final destination in space, million miles away

#102

Post by newaccount2021 »

s5300 wrote: post #58
EMM_386 wrote: post #9

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.

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 thin…

No post body was provided.

Re: James Webb telescope reaches its final destination in space, million miles away

#103

Post by zelos »

zionic wrote: post #94
PinkMilkshake wrote: post #3

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.…

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.

It's 2.5 times the mirror diameter, which is 6.25 times the light collecting area.

Re: James Webb telescope reaches its final destination in space, million miles away

#105

Post by jxcl »

zionic wrote: post #94
PinkMilkshake wrote: post #3

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.…

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.

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.

Re: James Webb telescope reaches its final destination in space, million miles away

#106

Post by joshspankit »

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.

Re: James Webb telescope reaches its final destination in space, million miles away

#107

Post by toxican »

Tenemo wrote: post #67
sillyquiet wrote: post #64

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 on…

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 ro…

He's also in the middle of a coast guard series he filmed last year. Pretty interesting stuff.

Re: James Webb telescope reaches its final destination in space, million miles away

#108

Post by NikolaeVarius »

pfdietz wrote: post #50
panda-giddiness wrote: post #39

Earlier quoted context omitted.

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 tent…

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.

Its nice to be able to design things around Sci-Fi. However, still in 2022, there is no spacecraft that allows EVAs anywhere.

Re: James Webb telescope reaches its final destination in space, million miles away

#109

Post by nexuist »

Dave3of5 wrote: post #98
arcticfox wrote: post #33

Earlier quoted context omitted.

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.

Actually Hubble was put into space by a (mostly) reusable system the space shuttle STS-31. That was about 30 years ago.

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

Re: James Webb telescope reaches its final destination in space, million miles away

#110

Post by [deleted] »

Sharlin wrote: post #80
PinkMilkshake wrote: post #3

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.…

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.

[deleted]
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