Work out the distance to the Moon with some string and a pencil

Опубликовано: 14 Январь 2025
на канале: Dr. Becky

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Before lasers how did we calculate the distance to the Moon? You can do the experiment at home, using the same method as the ancient Greeks, with some string and a pencil to make a homemade compass.

More detail on the lunar eclipse experiment: https://web.archive.org/web/201212091...

00:00 - How do we calculate the distance to the Moon today?
01:05 - Hipparcus and lunar eclipses
02:15 - Measuring the relative size of the Earth's shadow
03:35 - Eratosthenes and the size of the Earth
04:43 - Trigonometry time!
05:41 - The distance to the Moon
06:11 - Brilliant
07:18 - Bloopers

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👩🏽‍💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford. I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.

http://drbecky.uk.com
https://rebeccasmethurst.co.uk