The Webb telescope has 'perfectly misshaped' mirrors | Hacker News Reader

The Webb telescope has 'perfectly misshaped' mirrors

houstonchronicle.com

12 pointsStratoscope19 comments

> And since materials shrink when they get cold, scientists and engineers created mirrors that were imperfect on Earth but will have the perfect shape (and come into focus) in the frigid environment of space.

I'm surprised it can be done so precisely, including predicting the relative rates at which components will cool as it journeys through space. Does anyone know something that describes the engineering and solutions involved? Does it depend on materials? Modeling? Mechanisms for adjustment after it cools?

Why post a link to a Houston Chronicle article that requires registration? How many HN readers possibly want to join Houston Chronicle site?

It's perfectly readable with Javascript off.

Why would someone post an article to HN that requires disabling JS?

Why would someone reading HN complain about something that should be default behavior, besides the fact it can be arranged to be toggled by one click or hotkey?

ahh yes, much the same way Legos are "perfectly misshaped" marbles

https://12ft.io/proxy?q=https%3A%2F%2Fwww.houstonchronicle.c...

the first 6 words of this headline shot fear through me, jumping to the conclusion that something had gone wrong with the launch setup

I think that was the (clickbait) idea... :(

People still remember Hubble's first months. This is clearly a clickbaity title trying to capitalize on that.

This has nothing to do with Hubble's first months.

The article describes how the mirrors are deliberately misshapen at normal Earth temperatures, so when they cool down to their -380F/-230C/44K operating temperature they will then (hopefully!) be in focus.

I did not know that before; I learned about it and a few other interesting facts from this article.

Clickbaity title or not, I found it an informative read.

The headline is definitely playing off of fears of a repeat of the Hubble error.

Most readers of the Houston Chronicle are unware of that, I expect.

idk i hear space crap is kind of a big deal there?

not to mention most readers who care at all about this new telescope probably have indeed read about the old one..

Good points, though I won't take them that far. To be aware of the Hubble's issues at the time, you'd need to be at least ~40 years old now.

If something does go wrong there's no way to send a repair crew like on Hubble.

Talk about pressure to get everything right on the first try.

because L2 is so much more of a pain to reach?

It's not "misshaped" if it's precisely the way it's meant to be. The media need to stop trading credibility for clicks, before they run out. I flagged this article, if the idea is to give HN a pretext to talk about Webb, there are plenty of better articles out there to use.

That's what the article says.

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