
How many great minds does it take to invent a telescope? - Hooke
https://aeon.co/ideas/how-many-great-minds-does-it-take-to-invent-a-telescope
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DanAndersen
It's fascinating to learn about the transitional period of the Scientific
Revolution and just how all these various advances and changes in thinking
actually happened. It's usually a lot more complex than we think of now.

The article's mention of optical problems in early telescopes is actually
quite an important one when it comes to the history of geocentrism vs
heliocentrism and the Galileo affair. One of the objections to heliocentrism
is that if the Earth moved then we should expect to see stellar parallax,
which was not observed (certainly not with the observation technology at the
time). The Copernicans responded by positing that the stars were extremely far
away, but you can imagine how such an evidence-lacking response would seem
like trying to explain away one hypothesis by adding a new one. But in
addition, the geocentrists seemed to have solid observational evidence on
their side: the apparent diameter of stars when viewed through the telescope
either implied that the stars were close enough that we should be seeing
parallax with 1600s-era instruments, or that the stars are far away and all
absurdly giant in size.

It turned out that the manufacture of the telescopes themselves created an
optical illusion now known as an Airy disk (
[https://en.wikipedia.org/wiki/Airy_disk](https://en.wikipedia.org/wiki/Airy_disk)
), which makes the stars look like disks and thus have a misleading apparent
diameter. It wasn't until 1835 that this phenomenon was understood!

For anyone interested in the long and complex history of geocentrism,
helicentrism, Galileo and his contemporaries, I have to strongly recommend
reading the nine-part series of posts "The Great Ptolemaic Smackdown" by SF
author Michael Flynn. It makes for a wonderful bit of weekend reading, and
you'll come out of it with a great appreciation for the slow, methodical
process of scientific understanding:

Part 1: [http://tofspot.blogspot.com/2013/08/the-great-ptolemaic-
smac...](http://tofspot.blogspot.com/2013/08/the-great-ptolemaic-
smackdown.html)

Table of Contents: [http://tofspot.blogspot.com/2013/10/the-great-ptolemaic-
smac...](http://tofspot.blogspot.com/2013/10/the-great-ptolemaic-smackdown-
table-of.html)

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swayvil
Yesterday : how can messed up glass deliver any kind of respectable
observations?

Today : how can messed up <foo> deliver any kind of respectable observations?

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yasserd99
Inventing a telescope require many great minds, but inventing a whole universe
from scratch might not require intelligence. Think about that

