wings1295 reblogged
the-future-now-deactivated20170
🐸☕️
bipch erastosthenes schooled b.o.b. 2,230 years ago
Ok so this is cool but I always wondered how they knew the shadows were different at the same instant. I mean it is not like they had phones. How did they sync up that instant. I feel like that would be interesting to know but no one ever says.
^^^Does anybody know this one? How, that far apart, the time at which the shadows were observed was synced up? I am genuinely curious, not a goddamn moron asking a gotcha question. High/Low tide? (I live in the middle of the country I do not know for the precise habits of tidal activity.) The appearance of a star (or planet) in the sky? Something as utterly mundane as sunrise?
Well, first of all, it wasn’t actually pillars! Eratosthenes was told about a well in Syene that, in the summer solstice every year (June 21st) would be illuminated at the bottom entirely and without any cast shadows. This indicated that the sun was directly overhead. Going off that well known curiosity and an intelligent hunch, our dude Eratosthenes waited until high noon of the summer solstice to measure the angle of a shadow cast by a stick in Alexandria. (Sidenote: Eratosthenes was a librarian of the infamous Library of Alexandria.)
His next course of action was to hire bematists, surveyors of the time whose professional specialty was to measure distance by walking with equal length steps. They measured a distance between Alexandria and Syene of about 5000 stadia. (Guess where the word stadium comes from.) Once he had that measurement, Eratosthenes did his math-y thing, and there you have it.
ANSWER EVEN COOLER THAN I HOPED!!
Eratosthenes’ work was thorough enough that by the time he finished revising his calculations, he ended up only 66 km off of the actual polar circumference of the Earth, or an error margin of 0.16%. [wiki]
Source: mic.com
wings1295 reblogged
"She had studied the universe all her life, but had overlooked its clearest message: For small creatures such as we, the vastness is bearable only through love."
Carl Sagan (via retromantique)
oh gawd, my heart..!
(via spookychan)
wings1295 reblogged
alwaysmoneyinthebnanastand-deac
They get so hot that the nuclei of the atoms fuse together deep within them to make the oxygen we breathe. The carbon in our muscles, the calcium in our bones, the iron in our blood, all was cooked in the fiery hearts of long-vanished stars.
wings1295 reblogged
Somewhere Something by Francesca Buchko
wings1295 reblogged
victoriousvocabulary
What an astonishing thing a book is. It’s a flat object made from a tree with flexible parts on which are imprinted lots of funny dark squiggles. But one glance at it and you’re inside the mind of another person, maybe somebody dead for thousands of years. Across the millennia, an author is speaking clearly and silently inside your head, directly to you. Writing is perhaps the greatest of human inventions, binding together people who never knew each other, citizens of distant epochs. Books break the shackles of time. A book is proof that humans are capable of working magic.
Carl Sagan, Cosmos (via victoriousvocabulary)
¥€$
(via thehauntedrocket)
wings1295 reblogged
Carl Sagan on books.
Source: mydelineatedlife.blogspot.com
wings1295 reblogged
modernageviking-deactivated2014
Carl Sagan on books
wings1295 reblogged
It’s definitely a Sagan night.
wings1295 reblogged
betterlivingthroughjunkculture
Carl Sagan fan art FTW
Source: irkenidiot.deviantart.com
wings1295 reblogged
jamesgetsinshape-deactivated201
Such a great Sagan quote!
... the cosmos is also within us. We're made of star-stuff. We are a way for the cosmos to know itself.
Carl Sagan
wings1295 reblogged
love it. love it so much.
Some of the huge number of prints Mike Mitchell created for the show at Gallery 1988. Most of these are still available for $30 each:
Aquaman (and more) by Mike Mitchell