New and Ancient Lessons from Lunar Eclipses

Ancient perceptions of lunar eclipses weren’t as primitive as one might think. Some rigorous math was applied to these cosmic events that shaped our understanding of the solar system.

Hosted by: Hank Green (he/him)
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[TheDevler]

I feel so lucky to have been raising elementary age kids the past decade and a half. They've gotten to experience 2 lunar eclipses and one partial solar eclipse (90% totality over our house). And because they have a science enthusiast mom in me, I took them to an observatory to climb the ladder and look through the scope to see Titan and Saturn perfectly aligned for viewing in high detail. My older son came bounding down the ladder when his turn was over, SO excited because "MOM! I saw Saturn's RINGS! With my own EYES! Not like on TV or anything!!" Best. Vacation. Ever. Also, if you live in the PNW, you really should visit the Goldendale Observatory in Southern Washington. it's a fantastic experience!

[samwill]

People 2000+ years ago finding out how big the earth is, how far away it is and the size of its orbit using nothing but papyrus and math.
And there are people who legit think our world is flat.

[skrdman]

One of the things I love about astronomy is how accessible it is. There's a lot of basic principles that can be observed by simply looking up at the night sky, and taking some notes over time.

[ShawnHCorey]

You missed one thing the ancient astronomers were able to calculate: the relative longitude of their cities. Unlike a solar eclipse, a lunar eclipse happens at the same time for ever observer on Earth. The difference in the azimuth of the eclipse is the difference in longitude of the points on the Earth where the observations were made.

[thelostone]

All of sudden and only loosely related, I have Terry Jones saying “that my liege is how we know the Earth to be banana shaped”.

[joyl]

Loving the additional background information from ancient Greek scientists!

[willowmoon]

I adore the fact that fluffy is a genuine astrological term

[Beryllahawk]

Fantastic to know there are higher purposes for higher math, other than the suffering and tears of high school students :P
Also! Shout out for that GREAT T-shirt! I see that Journey to the Microcosmos reference!! Yay!!!!

[WRITER]

Aristotle found out the earth is sphere more than two millennium ago and people still argue that it's flat.

[poiuytrewq]

Love seeing white light distributed across the night time sky due to this effect.

[agnorat]

That’s a really cool shirt I wonder where I could get one 😉😉

[BytebroUK]

"Don't be silly - we have towns and cities down here. Of course the vents will look different between the night-time and an eclipse?!"
<I can actually imagine HG Wells saying that, btw!>

[reedspaulding]

I am wondering if you could edit it a bit closer. You missed cutting out a breath or two. If you had edited those out too, youcould have shortened the video by another.02 seconds.

[xtinmanx]

That's a cool shirt, there, Hank

[Bxu]

0:54 I think he’s trying to tell us something here 😑😂

[NihilisticRealism]

these videos will outlive you.

isnt that fun?

[cameronf]

I loved hearing about how a few ancient astronomers and philosophers accurately predicted all kinds of astronomical realities while likely being undernourished for decades while we have a rise in people *today* thinking the earth is flat.

That’s just funny to me.

[glcol]

How did Aristarchus time the moon going through the Earths shadow? Can't use a sun dial during a lunar eclipse, don't think he had a watch, so I am really curious. I'm sure he did it, just wonder how...

[DerMaikNichJa]

How do we know if we have exhausted the possibilities for more discoveries? Are there ways to measure this?

[huldu]

If those ancient greeks had computers we would have colonized the galaxy by now.