π¬ Neptune is found by maths (1846)
The telescope used is now on display at the Deutsches Museum in Munich.
Where: Old Berlin Observatory
Nearby on the globe: Reichstag Building β π Open the 3D globe
π On This Day: September 23
September 23, 1846: Neptune is found by maths. On the night of 23 September 1846, Johann Galle at the Berlin Observatory first spotted Neptune through a telescope. It was less than one degree from where France's Le Verrier, by calculating the motion of another planet, had predicted a planet would be.
β¨ More events on this day
- 1756 π‘ Engineer John Loudon McAdam was born in 1756; his way of building smooth roads from layers of small stones, called 'macadam', spread around the world.
- 1791 π Astronomer Johann Franz Encke was born in 1791; he worked out the path of a comet that returns every three years, and it is now called Encke's Comet.
- 1819 π¬ Physicist Hippolyte Fizeau was born in 1819; using a spinning toothed wheel and a mirror, he measured the speed of light here on Earth.
π§ Question of the day
How did Le Verrier know where Neptune was?
- A bird told him
- By calculating another planet's motion
- He saw it in a dream
Show the answer
Answer: By calculating another planet's motion
Questions
What happened on September 23?
September 23, 1846: Neptune is found by maths. It happened in Old Berlin Observatory.
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