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How Astrolabes Work

Author's Note

It occurred to me as I was wrapping up this story that you could make a digital astrolabe to run on your smartphone or tablet. I did a quick search on my phone and -- would you believe it? -- there's an app for that! Check out Astrolabe Clock by TwoNineEight Software. It's free, although perhaps a little less satisfying to use than an astrolabe in its pure, analog form.

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