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

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331–340 of 350 posts

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

#331

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.…

basically spaceships to capture photons!

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

#332

Earlier quoted context omitted.

Which part? The bit with Nixon is well known (see, for example, John Logsdon's book "After Apollo?"). As for SLS, it's called the "Senate Launch System" for a reason. Shelby in particular has saved it, to the extent that work on propellant depots was targeted for extermination (no one in NASA is to utter the "D" word.) Depots and propellant transfer render irrelevant the SLS's supposed advantage of large payload mass…

The Nixon bit isn't well known, but thanks for the reference. I've never heard the rest. Is there a source? It's easy to attribute political reasons to whatever Congress does, because Congress is filled with politicians. But members have other motives too, and private businesses, despite the hype, have plenty of corrupt and political motives - throwing contracts to allies and friends, undermining enemies, etc. - thou…

https://arstechnica.com/science/2019/08/rocket-scientist-say...

which references

https://twitter.com/SciGuySpace/status/1156294287245660160

Quote:

> Digging through some old notes. Found this quote from a few years ago from a senior academic engineering source at the time.

> "Senator Shelby called NASA and said if he hears one more word about propellant depots he’s going to cancel the space technology program."

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

#333
post #22

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.

This simple 20 seconds video was far better than hundreds of those link. I mean I couldn't visualize the whole set up and orientation and this video made things crystal clear.

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

#334

Earlier quoted context omitted.

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...

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.

Maybe it’s zero relative to the earth-moon center of mass, and/or the rotation simply isn’t that exact for the relative speed to be zero.

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

#335

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, multip…

The sky calls to us. If we do not destroy ourselves, we will one day venture to the stars. -Carl Sagan

And that path currently goes thru an autist welding up rockets in tents on a beach.

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

#336
post #67

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 so creepily "wholesome" and obviously propaganda-adjacent in a Chris Pratt way it makes me not watch his videos.

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

#337

Earlier quoted context omitted.

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.

It had one test flight. Hardly comparable to a system which had (six?) models fully deployed and operational.

It didn't fail for any technical reason though, the whole government behind it was stumbling at the time on it's way to full collapse from a heady medley of internal and external forces.

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

#338

Earlier quoted context omitted.

> 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…

Have there been any interesting breakthroughs or findings from the science done aboard the ISS?

There's also the NICER mission (Neutron Star Interior Composition Explorer; https://heasarc.gsfc.nasa.gov/docs/nicer/nicer_about.html) which is a payload on the ISS that's mapped pulsar surfaces: https://www.youtube.com/watch?v=zukBXehGHas

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

#339
post #212

Earlier quoted context omitted.

Correct. And since the beryllium mirrors are 8 times harder than steel, it's probably a tough job.

Not really. They are quite thin and the deformation is minute, on the order of less than a micron at the largest point.

Edit: that should have been 10 micron.

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

#340

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.…

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.

Space shuttle was not that big. It was literally transported on an airliner and a fraction of the size.
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