AD | To try everything Brilliant has to offer for free for a full 30 days, visit https://brilliant.org/DrBecky and you'll also get 20% off an annual premium subscription. | How do we know the scale of the Solar System? How do we know that the Earth is around 150 million km from the Sun? Sure today we can use radar to bounce light back and forth between objects to work out how far away they are, but before that, it’s not like people could break out a giant tape measure to do this, scientists had to get clever about it, they had to use trigonometry to get at the very first measurement of the distance of the Earth from the Sun in the early 1700s using a transit of Venus, and in doing so unlock the entire scale of the Solar System. So this video, is for anyone that’s ever said that trigonometry is not useful, because it most definitely is! If you’re an astronomer anyway...

More in-depth look at the maths behind this calculation: http://www.phy6.org/stargaze/Svenus1.htm


Video filmed on a Sony ⍺7 IV

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👩🏽‍💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford (Christ Church). 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