The first measurement showing light has a finite speed. In this paper from 1676 Ole Rømer proved that light doesn't travel instantly using Jupiter's moon Io as a clock in the sky. Io is eclipsed by Jupiter's shadow about every 42.5 hours. When Earth is moving away from

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  1. #1

    The Tragedy of the Commons - why would rational people destroy the one thing they all depend on? Garrett Hardin’s 1968 answer: on a shared pasture, each extra cow pays its owner i…

    Fermat's Library @fermatslibrary ·
    The Tragedy of the Commons - why would rational people destroy the one thing th…
  2. #2

    Happy Birthday Carl Sagan 🎂 When asked about the the purpose of sending messages out into the universe when it might take thousands of years to get any sort of answer Carl Sagan s…

    Fermat's Library @fermatslibrary ·
    Happy Birthday Carl Sagan 🎂 When asked about the the purpose of sending message…
  3. #3

    Marie Curie (1867) and Lise Meitner (1878) were born 11 years apart on the same day: November 7. Curie won 2 Nobel Prizes. Meitner was nominated 48 times: 29 in physics, 19 in che…

    Fermat's Library @fermatslibrary ·
    Marie Curie (1867) and Lise Meitner (1878) were born 11 years apart on the same…
  4. #4

    Discovery of explicit solution formulas for Polynomial equation: • j=2 Pythagoras (500 BC) • j=3 Girolamo Cardano (1545) • j=4 Lodovico Ferrari (1540) • j≥5 No general formula exi…

    Fermat's Library @fermatslibrary ·
    Discovery of explicit solution formulas for Polynomial equation: • j=2 Pythagor…
  5. #5

    James Clerk Maxwell died exactly 147 years ago today, aged 48 of the same abdominal cancer that had killed his mother at the same age, when he was 8 years old. That same year Albe…

    Fermat's Library @fermatslibrary ·
    James Clerk Maxwell died exactly 147 years ago today, aged 48 of the same abdom…
  6. #6

    As of today Voyager 1 is one light-day from Earth - 25.9 billion km (16.1 billion miles) away. A radio signal now takes 24 hours to reach it. In ~50 years, it has traveled about 1…

    Fermat's Library @fermatslibrary ·
    As of today Voyager 1 is one light-day from Earth - 25.9 billion km (16.1 billi…

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