[HN Gopher] Cosmic Dawn: The Untold Story of the James Webb Spac...
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       Cosmic Dawn: The Untold Story of the James Webb Space Telescope
        
       Author : baal80spam
       Score  : 44 points
       Date   : 2025-07-19 19:24 UTC (3 days ago)
        
 (HTM) web link (plus.nasa.gov)
 (TXT) w3m dump (plus.nasa.gov)
        
       | fusslo wrote:
       | 1hr 38 minutes
       | 
       | hell yes I'm watching this. I need to find a 'download' button to
       | watch it at 1.5x tho
       | 
       | edit: actually, right click the video player when it's playing
       | and there are speed controls
        
         | CamperBob2 wrote:
         | Also on YouTube at https://www.youtube.com/watch?v=uSMGENDH_QI
         | .
        
           | creativenolo wrote:
           | Werid that a path to getting a download is a YouTube link but
           | here we are
        
             | MarceColl wrote:
             | I think it was a path to be able to see it in 1.5x, not to
             | download it
        
       | jesuslop wrote:
       | Things are kinda weird. We had a reasonable notion of "now", as
       | in... a photo. Came 1905 relat. and that blows the idea up, there
       | is no more a consensual concept of "now". But though not
       | consensual, the photo definition, even if dependent on the
       | observer, is still there. One thing that an earlier documentary
       | on the Webb experiment impressed on me is that with that "now" so
       | defined, the farther the things I see are the earlier, so it is
       | legit that we are seeing big bang "now" (modulo some shit
       | occluding). It is geometrically also weird. We can look around 2D
       | in 360 degrees and see bbang photons coming from everywhere, look
       | 3D spherically around every direction receiving bbang photons.
       | Yet all photons are sourced in a single point-like event (bbang,
       | or post bbang "first light" in fortunate ESA terms). Photons came
       | to us from behind in spacetime from our causal past light-cone,
       | but that cone joins base with the forward oriented bbang causal
       | future light cone, so any valid signal one gets must be inside
       | that region of joined cones. The pic has to be the same as in
       | "suspension" in topology wiki page.
        
         | AnimalMuppet wrote:
         | A couple of nits:
         | 
         | The finite speed of light was known before 1905. It was known
         | by 1676.
         | 
         | Second, we see "big bang photons" in the CMB, but we're not
         | seeing the big bang. We're seeing the glow from stuff at the
         | time when the universe became transparent, that is, no longer a
         | plasma.
        
       | TheAmazingRace wrote:
       | Honestly, I'm impressed how they managed to nail the design so
       | well with JWST. And sidebar, love the RAD-hardened IBM PowerPC
       | CPU on the telescope.
        
       | chrisweekly wrote:
       | I saw this at the Museum of Science in Cambridge, MA, in all its
       | IMAX glory. The images are profoundly beautiful, and the ideas
       | about seeing so far back in time are a real trip (even for the
       | relatively well-informed layperson). Also, the telescope's
       | creation, how close it came to being scrapped, the long-shot odds
       | and multiple SPoFs that it survived... makes for a really
       | engaging story.
        
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       (page generated 2025-07-22 23:00 UTC)