1255: "Columbus"

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Re: 1255: "Columbus"

Postby SlyReaper » Fri Aug 23, 2013 3:22 pm UTC

davidstarlingm wrote:
wumpus wrote:The two embarrassing parts for Spain were that nobody bothered to check the distance/curvature between Madrid and Toledo (even though the Greeks who wrote about the size of the Earth describe how they figured it out) and that every Portuguese captain* (and anybody else who knew the trick of running the Latitudes) knew exactly how big the Earth was.

* wouldn't you hate to explain where all this gold was coming from when you *knew* that China and India were 10,000+ miles away (note that sailing down the horn of Africa seems to be the shorter route).

I wonder whether Columbus's return caused any cartographers to consider this possibility that the Earth was a different size/shape than they had previously believed, or if they all basically knew for certain that he had simply discovered a new continent.

Or if there were conspiracy theories about how he must be secretly sailing down around Africa.

SlyReaper wrote:What I love about that misconception is that there are plenty of man-made objects visible from space, and the Great Wall of China isn't one of them.

What's the smallest man-made object visible from space? We can take "visible from space" to mean "visible to the naked eye from the ISS when there aren't any clouds blocking the view". Could one of the ISS astronauts see a laser pointer at night if it was trained on the ISS?


Smallest man-made object visible from the ISS? That would be the ISS. Or one of the smaller objects/components on board the ISS or docked spacecraft.

But yeah, I'm sure a sufficiently powerful laser pointer would be able to transmit a few photons to the eyes of an orbiting astronaut. How powerful it would need to be to significantly outshine the area around the laser pointer... I can't really be arsed to the the maths on that one. One complicating factor will be that the atmosphere will scatter the laser light, so it won't be a neatly collimated beam by the time it reaches the spaceman.
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Re: 1255: "Columbus"

Postby orthogon » Fri Aug 23, 2013 3:26 pm UTC

What did they think about gravity at the time? Was it just natural to assume it would be normal to the Earth's surface everywhere, or did they think it might act in the same direction everywhere and that you might fall off when you got to the "underside"? (I guess they'd been to India where gravity should have been nearer to the horizontal than the vertical, so they had a pretty good idea.)
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Re: 1255: "Columbus"

Postby ctdonath » Fri Aug 23, 2013 3:34 pm UTC

Yin-yang symbols for heads.
Just sayin'.

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Re: 1255: "Columbus"

Postby pyronius » Fri Aug 23, 2013 3:35 pm UTC

I just realized that all this time hearing the Columbus myth I've never heard anyone raise the single most obvious objection. If Columbus "knew the earth was round" why do children never just ask "how?" Because clearly he was some kind of genius then and that seems to be lacking from the story.

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Re: 1255: "Columbus"

Postby nowhereman » Fri Aug 23, 2013 3:45 pm UTC

davidstarlingm wrote:What's the smallest man-made object visible from space? We can take "visible from space" to mean "visible to the naked eye from the ISS when there aren't any clouds blocking the view". Could one of the ISS astronauts see a laser pointer at night if it was trained on the ISS?


Assuming you mean a standard hand held laser pointer (5 milliwatts). Also assuming the wavelength of said pointer is around 510 nm (yellow-green), the answer could be yes... assuming alot. I determined this by assuming the point of light was eimmited from a 1mm point at ground surface and then determined the area of the circle at the altitude of the ISS (thanks to WolframAlpha again for just happening to know the altitude). Then I determined the number of photons being emmited from said laser pointer and adjusted for the ratio of the areas of the circles. I came up with an estimation of 1700 photons per 1/10th second. This exceeds the 100% detection rate (150 photons 1/10) and so would be detectable.

However, to put a damper on your idea, here are some problems. First, this assumes the nearby area is dim. No cities can be close to you. Random guess, I'll assume 50 miles is enough. Also, the atmosphere will scatter the light. My number is based upon a perfectly collumated stream of photons. This stream will probably not be. Finally, you need to get those astronauts to pay attention. I generally assume they are busy and really don't care about faint points of light.
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Re: 1255: "Columbus"

Postby Wnderer » Fri Aug 23, 2013 4:28 pm UTC

pyronius wrote:I just realized that all this time hearing the Columbus myth I've never heard anyone raise the single most obvious objection. If Columbus "knew the earth was round" why do children never just ask "how?" Because clearly he was some kind of genius then and that seems to be lacking from the story.


How? Because he saw the top of the ships masts last as they sank over the horizon. I recall seeing that in some educational program.

Most educated people knew the world was round but most people weren't educated. There were also other goofy beliefs like the seas boiled near the equator and the sea turning to weeds or mud and of course sea monsters. I admire the sheer audacity of Columbus's voyage. Leif Ericson's island hopping across the North Atlantic or Vasco De Gama sailing along the African coast pale in comparison with sailing from Spain to Haiti across the Atlantic Ocean.

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Re: 1255: "Columbus"

Postby jpvlsmv » Fri Aug 23, 2013 4:38 pm UTC

davidstarlingm wrote:
SlyReaper wrote:What I love about that misconception is that there are plenty of man-made objects visible from space, and the Great Wall of China isn't one of them.

What's the smallest man-made object visible from space? We can take "visible from space" to mean "visible to the naked eye from the ISS when there aren't any clouds blocking the view". Could one of the ISS astronauts see a laser pointer at night if it was trained on the ISS?

Probably one of the extra bolts or satellite bits that's floating around up there. Otherwise, a CubeSat.

Voyager I would hold the title of "smallest man-made object visible from (near-)?interstellar space" which I think is more interesting.

And Alan Shepard's golf balls are probably the smallest man-made object visible from the moon.

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Re: 1255: "Columbus"

Postby Plasma Man » Fri Aug 23, 2013 5:45 pm UTC

I'm now wondering what man-made objects can be seen from New Netherlands.
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Re: 1255: "Columbus"

Postby San Fran Sam » Fri Aug 23, 2013 5:57 pm UTC

Plasma Man wrote:I'm now wondering what man-made objects can be seen from New Netherlands.


Well, there's the King Gustav V tower in New Sweden.

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Re: 1255: "Columbus"

Postby Pfhorrest » Fri Aug 23, 2013 6:03 pm UTC

pyronius wrote:I just realized that all this time hearing the Columbus myth I've never heard anyone raise the single most obvious objection. If Columbus "knew the earth was round" why do children never just ask "how?" Because clearly he was some kind of genius then and that seems to be lacking from the story.

That's a question that not enough people seem to ask about anything. "So-and-so knows such-and-such" is too often accepted solely on the intellectual authority of so-and-so: they're just smarter than everyone else and we should just believe them about such-and-such, don't bother questioning how they know, you're dumb and wouldn't understand.

Combine that with our naive tendency to think that modern people are smarter than medieval people (rather than just there being more accumulated knowledge which is more available to more people), and it's easy to just look at it as "well Columbus was just the first person who was smart enough to see that the world was round, which is now obvious to all of us because we're all smarter than that these days".


To go of on a bit of a tangent about this, it strikes me now: there is a kind of wisdom in knowing the limits of your own wisdom and when you should defer to people who know better than you do, so I don't want to denigrate the practice in general of deferring to credible authorities -- that is, people whose word is taken as authoritative because they've proven to be usually right, not just for any social status reason -- as otherwise you get all kinds of kooks who think that they've disproven all kinds of well-studied things that they don't even begin to understand. This in turn makes me think of the Dunning-Kruger effect, whereby intelligent people underestimate their own intelligence (because they know that there's a lot they don't know) and unintelligent people overestimate their intelligence (because they don't even know that they don't know so much), and leads me to wonder if perhaps that has a role in why scum seems to rise to the top of societies, and why the masses who are generally better than that scum just accept it: the masses, who are largely less than stunning in their own faculties, at least know that they are not experts on a lot of things, and so are happy to defer to those who are experts; but then there are kooks who don't realize they're even less fit to lead than all the other morons, and go around pumping themselves up as geniuses with solutions to all of life's problems; the masses see the kooks purporting to be experts, "wisely" defer to them, and we end up with the people least fit to lead being handed the reigns of society, over and over again.

TL;DR: Maybe most political leaders are the social analogue of science kooks, the masses are like all masses and believe them, and the problem is that we lack the political analogue of real scientists to debunk all the kooks.
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Re: 1255: "Columbus"

Postby Chicagojon » Fri Aug 23, 2013 7:46 pm UTC

So...

Comic about the 'fact' of how Columbus 'knew' the world was round is followed by a forum thread discussion where multiple people explain the 'real facts' of how he just got the math wrong in the size of the world, tricked Ferdinand/Isabella, ran into an undiscovered continent, etc.

Well played Randall, well played...


For what it's worth, I believe that people were fishing 'new world' waters long before Columbus and the knowledge of land was known to him. He knew he was going to hit land because he had secondhand (or maybe even 1st) accounts of people who had sailed west to land. He may not have known exactly what land or exactly where, but he knew he'd get there. I tend to assume that the explorers and new world conquistadors are 90% myth / 10% fact.

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Re: 1255: "Columbus"

Postby Kaelin » Fri Aug 23, 2013 7:46 pm UTC

davidstarlingm wrote:What's the smallest man-made object visible from space? We can take "visible from space" to mean "visible to the naked eye from the ISS when there aren't any clouds blocking the view". Could one of the ISS astronauts see a laser pointer at night if it was trained on the ISS?


While the 5 mW laser may have problems, supposedly a 1W laser works.

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Re: 1255: "Columbus"

Postby 1001usernames » Fri Aug 23, 2013 8:03 pm UTC

Wnderer wrote:
pyronius wrote:I just realized that all this time hearing the Columbus myth I've never heard anyone raise the single most obvious objection. If Columbus "knew the earth was round" why do children never just ask "how?" Because clearly he was some kind of genius then and that seems to be lacking from the story.


How? Because he saw the top of the ships masts last as they sank over the horizon. I recall seeing that in some educational program.

Most educated people knew the world was round but most people weren't educated. There were also other goofy beliefs like the seas boiled near the equator and the sea turning to weeds or mud and of course sea monsters. I admire the sheer audacity of Columbus's voyage. Leif Ericson's island hopping across the North Atlantic or Vasco De Gama sailing along the African coast pale in comparison with sailing from Spain to Haiti across the Atlantic Ocean.


Not just most educated people, but also sailors and anyone living near the sea. It wasn't a revolutionary idea, though it is true that there were other weird superstitions.

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Re: 1255: "Columbus"

Postby Pfhorrest » Fri Aug 23, 2013 8:14 pm UTC

Chicagojon wrote:For what it's worth, I believe that people were fishing 'new world' waters long before Columbus and the knowledge of land was known to him. He knew he was going to hit land because he had secondhand (or maybe even 1st) accounts of people who had sailed west to land. He may not have known exactly what land or exactly where, but he knew he'd get there. I tend to assume that the explorers and new world conquistadors are 90% myth / 10% fact.

I've heard that suggested before, but if Columbus really thought that it was a new world (and not just that these stories disproved the accepted size of the world), why pitch it as "I'm gonna sail to India"? I'd think "I'll claim an entire new world in the name of Spain" would be a better sales pitch.
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Re: 1255: "Columbus"

Postby 1001usernames » Fri Aug 23, 2013 8:18 pm UTC

orthogon wrote:What did they think about gravity at the time? Was it just natural to assume it would be normal to the Earth's surface everywhere, or did they think it might act in the same direction everywhere and that you might fall off when you got to the "underside"? (I guess they'd been to India where gravity should have been nearer to the horizontal than the vertical, so they had a pretty good idea.)


Yeah, I know the general principle of how it works was known to be true at least from the time of Dante, and almost certainly from the Greek era; if you read the "Inferno," he actually has Dante and Virgil switch directions when they are climbing down the lowest pit of Hell (along Satan's legs, actually!). I'm willing to bet that Dante, being the Aristotelian that he is, got it from Aristotle, though I don't know that for a fact. The physics of it is a little off (he assumes that there's a sort of instant switch, instead of gradually decreasing gravity, then gradually increasing in the other direction), but the knowledge is still there.

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Re: 1255: "Columbus"

Postby 1001usernames » Fri Aug 23, 2013 8:21 pm UTC

Pfhorrest wrote:
Chicagojon wrote:For what it's worth, I believe that people were fishing 'new world' waters long before Columbus and the knowledge of land was known to him. He knew he was going to hit land because he had secondhand (or maybe even 1st) accounts of people who had sailed west to land. He may not have known exactly what land or exactly where, but he knew he'd get there. I tend to assume that the explorers and new world conquistadors are 90% myth / 10% fact.

I've heard that suggested before, but if Columbus really thought that it was a new world (and not just that these stories disproved the accepted size of the world), why pitch it as "I'm gonna sail to India"? I'd think "I'll claim an entire new world in the name of Spain" would be a better sales pitch.


He didn't know that there was another continent in there; there were a few (a very few) people who had hit new land, but he just assumed it was the islands off the coast of India. He was actually (officially) looking for a new shipping route to India, which would have been VERY lucrative, because the Portuguese had laid claim to the one around the Horn of Africa, and were quite able to defend that claim.

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Re: 1255: "Columbus"

Postby Wnderer » Fri Aug 23, 2013 8:41 pm UTC

1001usernames wrote:
orthogon wrote:What did they think about gravity at the time? Was it just natural to assume it would be normal to the Earth's surface everywhere, or did they think it might act in the same direction everywhere and that you might fall off when you got to the "underside"? (I guess they'd been to India where gravity should have been nearer to the horizontal than the vertical, so they had a pretty good idea.)


Yeah, I know the general principle of how it works was known to be true at least from the time of Dante, and almost certainly from the Greek era; if you read the "Inferno," he actually has Dante and Virgil switch directions when they are climbing down the lowest pit of Hell (along Satan's legs, actually!). I'm willing to bet that Dante, being the Aristotelian that he is, got it from Aristotle, though I don't know that for a fact. The physics of it is a little off (he assumes that there's a sort of instant switch, instead of gradually decreasing gravity, then gradually increasing in the other direction), but the knowledge is still there.


Aristotelian Gravity worked like a type of buoyancy. The universe was geocentric and all five of the elements wanted to organize themselves into layers, so that earth was at the center, water was in a shell above earth, air was in a shell above water, fire was in a shell above air and aether was in a shell above fire. They knew the earth was round but they also thought the earth was the center of the universe.

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Re: 1255: "Columbus"

Postby Chicagojon » Fri Aug 23, 2013 9:00 pm UTC

1001usernames wrote:
Pfhorrest wrote:
Chicagojon wrote:For what it's worth, I believe that people were fishing 'new world' waters long before Columbus and the knowledge of land was known to him. He knew he was going to hit land because he had secondhand (or maybe even 1st) accounts of people who had sailed west to land. He may not have known exactly what land or exactly where, but he knew he'd get there. I tend to assume that the explorers and new world conquistadors are 90% myth / 10% fact.

I've heard that suggested before, but if Columbus really thought that it was a new world (and not just that these stories disproved the accepted size of the world), why pitch it as "I'm gonna sail to India"? I'd think "I'll claim an entire new world in the name of Spain" would be a better sales pitch.


He didn't know that there was another continent in there; there were a few (a very few) people who had hit new land, but he just assumed it was the islands off the coast of India. He was actually (officially) looking for a new shipping route to India, which would have been VERY lucrative, because the Portuguese had laid claim to the one around the Horn of Africa, and were quite able to defend that claim.


What he was 'officially' doing got him the money, but that doesn't explain his purpose. My understanding/belief is that what he was actually doing/wanted was to become famous just as much as he wanted to be rich. IIRC that's exactly what he wrote into his first contract and subsequent ones. The first didn't get a portion of future sales of goods from India (open a route) it gave him money for any goods he brought back. Later revisions to the contract after the 1st voyage were more about being a governor than anything else.

As far as 'I'll claim an entire new world in the name of Spain' -- you're already assuming that this was considered 'new' yet ignoring the possibility that the reason it wasn't claimed/explored may have simply been because people knew it was too far away and too impractical to claim/hold.

I have to dig up my Columbus original sources file to make better arguments, but my general view is that if it's something you were taught about the earliest and/or most famous explorers, it's definitely not completely true and most likely is very loosely based on truth.

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Re: 1255: "Columbus"

Postby Quizatzhaderac » Fri Aug 23, 2013 9:11 pm UTC

How do you know the world is a sphere?

Greek: We've done a bunch of tests with angles of sunlight.

Victorian: We've sailed around the whole thing with precise cartography instruments.

Modern: We went really far away from it and took pictures from different angles.

I suspect the Columbus myth propagated because people believed the best evidence for the world being round was also what proved it. Who wants to bet that eventually people will be saying the Apollo program was what proved the Earth was a sphere?
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Re: 1255: "Columbus"

Postby bmonk » Fri Aug 23, 2013 9:51 pm UTC

oelbert wrote:Yeah, the Greeks proved the earth was round, and people in medieval Europe knew it. The misconception that Columbus proved that the earth was round bugs the heck out of me...

The new element Columbus introduced was to claim it was much smaller than previous estimates--and he was wrong.

There is some evidence that he had figured out the seasonal winds, which would allow him to get much further west before he had to return east or risk running out of food and water.
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Re: 1255: "Columbus"

Postby Wlerin » Fri Aug 23, 2013 11:42 pm UTC

Uggh, how dare she confuse Columbus with Brendan!

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Re: 1255: "Columbus"

Postby Jeltz » Sat Aug 24, 2013 1:58 am UTC

Wnderer wrote:I admire the sheer audacity of Columbus's voyage. Leif Ericson's island hopping across the North Atlantic or Vasco De Gama sailing along the African coast pale in comparison with sailing from Spain to Haiti across the Atlantic Ocean.


Vasco Da Gama did not sail along the African coast all the way though, in the South Atalnatic it is better to follow the winds and almost go all the way to Brazil.

http://www.ducksters.com/biography/expl ... a_gama.php

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Re: 1255: "Columbus"

Postby orthogon » Sat Aug 24, 2013 10:32 am UTC

Chicagojon wrote: ... My understanding/belief is that what he was actually doing/wanted was to become famous just as much as he wanted to be rich.

Judging by his obsession with women's nipples, my impression is that he wasn't getting enough, and what he actually wanted was to get laid.

Of course, that amounts to the same thing if you take the view that most male ambition and risk-taking is fundamentally about sexual competition.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1255: "Columbus"

Postby NumberFourtyThree » Sat Aug 24, 2013 2:34 pm UTC

meat.paste wrote:
dalcde wrote:C'mon, "round" is just a lazy way to say "spherical"1

1Technically speaking, ball-shaped


Really technically speaking, it's an oblate spheroid. With 3 nipples to rain milk down on the turtles holding the planet up. (It's turtles all the way down, you know.)


I remember once I saw some comic where some guy jumped off the edge of the world with a rope tied around his waist, and saw a stack of turtles, but like 4 or 5 down there was an armadillo instead, and he said "Aha! An armadillo! I knew it couldn't be turtles all the way down!" I tried a google search but couldn't find the comic and I can't remember for sure where I saw it.
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Re: 1255: "Columbus"

Postby shokoshu » Sat Aug 24, 2013 4:27 pm UTC

Who cares about Columbus, I finally know how to get to Valinor! So obvious in hindsight!

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Re: 1255: "Columbus"

Postby electricmayhem » Sat Aug 24, 2013 7:10 pm UTC

Long time reader, first time poster. This could very well be the funniest thing I've ever seen here.

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Re: 1255: "Columbus"

Postby Alexius » Sat Aug 24, 2013 10:38 pm UTC

wumpus wrote:
Pfhorrest wrote:From what I've read, the reason everyone else was hesitant to fund Columbus was because they knew the world was round and how big it was and that no ship could survive such a long journey on the open sea as it would take to sail all the way from Europe to Asia the long way around, if it was nothing but water the whole way.


The two embarrassing parts for Spain were that nobody bothered to check the distance/curvature between Madrid and Toledo (even though the Greeks who wrote about the size of the Earth describe how they figured it out)

The method used by Eratosthenes requires one of the measurement points to be between the tropics, to be fair, which none of Spain is. It does only require minimal modification to be used outside the tropics, though.

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Re: 1255: "Columbus"

Postby Goof » Sun Aug 25, 2013 12:45 am UTC

In defense of Columbus: he had concrete evidence, not theory, to support his views; for example, storms had borne strange bird from the west, and the ocean had carried green logs from the west. There must be some land fairly nearby that had produced these. And that land had to be China [this was his error]. He wasn't lucky that he found land well before China — he knew it was there.

Aside: while my teachers taught that everyone else in the 15th century thought that the world is flat, schools apparently no longer do so. Progress! Next step: an official Eratosthenes Day!

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Re: 1255: "Columbus"

Postby Goof » Sun Aug 25, 2013 1:49 am UTC

pyronius wrote:I just realized that all this time hearing the Columbus myth I've never heard anyone raise the single most obvious objection. If Columbus "knew the earth was round" why do children never just ask "how?" Because clearly he was some kind of genius then and that seems to be lacking from the story.


If the earth is flat, and you stand on the seashore watching a ship sail away from you, the ship would be entirely visible until it got too far away to see. But up until the last moment, you would see the whole ship. And if you then brought out a telescope, the ship would be again visible. What actually happens, though, is that the ship disappears from the hull up, and vanishes entirely while it is still well within the power of your eyes. This happens because the ship goes over the horizon, and is hidden by the curvature of the earth. The only people who believed the earth is flat were those who never lifted their eyes from the furrow.

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Re: 1255: "Columbus"

Postby KarenRei » Sun Aug 25, 2013 12:49 pm UTC

Wnderer wrote:
1001usernames wrote:
orthogon wrote:What did they think about gravity at the time? Was it just natural to assume it would be normal to the Earth's surface everywhere, or did they think it might act in the same direction everywhere and that you might fall off when you got to the "underside"? (I guess they'd been to India where gravity should have been nearer to the horizontal than the vertical, so they had a pretty good idea.)


Yeah, I know the general principle of how it works was known to be true at least from the time of Dante, and almost certainly from the Greek era; if you read the "Inferno," he actually has Dante and Virgil switch directions when they are climbing down the lowest pit of Hell (along Satan's legs, actually!). I'm willing to bet that Dante, being the Aristotelian that he is, got it from Aristotle, though I don't know that for a fact. The physics of it is a little off (he assumes that there's a sort of instant switch, instead of gradually decreasing gravity, then gradually increasing in the other direction), but the knowledge is still there.


Aristotelian Gravity worked like a type of buoyancy. The universe was geocentric and all five of the elements wanted to organize themselves into layers, so that earth was at the center, water was in a shell above earth, air was in a shell above water, fire was in a shell above air and aether was in a shell above fire. They knew the earth was round but they also thought the earth was the center of the universe.


To be fair, not *all* ancient Greek scientists thought that Earth was the center of the universe. While his measurements were off by a factor of 20 due to an error of a couple degrees in a measurement, Aristarchus correctly came to the conclusion that the sun is much further away than the moon, and since they take up approximately the same size in the sky, much larger - than not just the moon, but than the Earth as well. He thus proposed that the Earth orbits around the sun. His texts doing so have not survived, but mention of them has. The obvious criticism was that if the Earth revolved around the sun, then one should see parallax in the stars (obviously, his response was that the stars were way far away, but in the time of the Greeks, such distances probably seemed absurd to many astronomers, leading to it generally being seen more as a rival theory than the predominant one).

Archimedes once used Aristarchus's work to estimate how many grains of sand it would take to fill the universe - and, by more important side-calculation, the diameter of the universe. He makes a weird assumption that the day-night solar parallax is the same as the annual stellar parallax, and also contains Aristarchus's measurement errors, yet comes to the conclusion that the universe is what we'd today call two light years in diameter.

Aetios says that Aristarchus "sets the sun among the fixed stars and holds that the earth moves around the elliptic", which would seem to imply that he thought the stars were just other suns, and thus it would be natural to place them much further away for them to appear so dim.

Based on his figures, Aristarchus apparently estimated the human limit of angular discrimination at about 0.0001 radians. If this is correct, then it would imply that in Aristarchos's universe the stars were at least on the order of tens of thousands of AU away (1 light year ~= 63.000 AU).

It's such a shame that nothing directly from Aristarchus has survived, because the mentions of his work really are fascinating. And clearly he was known in the ancient world. And there were other scientists who followed up on his work. Poseidonius, for example, got a much more accurate measurement of the distance from the earth to the sun (and thus size of the sun), only off by half - and suggested that other stars can even exceed the sun in size. Seleucus (whose works were also lost) also reportedly argued for a heliocentric universe, and more than that, an infinitely large one (his reasoning for heliocentrism was not based on astronomical measurements, but is believed to have been based on the tides). And on and on - so we know Aristarchus was hardly alone. Heck, given that we know that this was being talked about for centuries on end, and the figures refined and such, and that it was proposed that the sun itself was just another star - I wouldn't be shocked to learn of the ancient Greeks had gotten past heliocentrism itself.

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Wnderer
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Re: 1255: "Columbus"

Postby Wnderer » Sun Aug 25, 2013 10:35 pm UTC

KarenRei wrote:
Wnderer wrote:... They knew the earth was round but they also thought the earth was the center of the universe.


To be fair, not *all* ancient Greek scientists thought that Earth was the center of the universe. ...


Yes, the Greeks had a lively and open debate on the nature of the universe, but by 'they' I was referring to Columbus's contemporaries. I believe by the middle ages Aristotle and Ptolemy had become established dogma and that's why Copernicus and Galileo challenging these authorities was such a big deal.

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Re: 1255: "Columbus"

Postby da Doctah » Mon Aug 26, 2013 4:30 am UTC

KarenRei wrote:Archimedes once used Aristarchus's work to estimate how many grains of sand it would take to fill the universe - and, by more important side-calculation, the diameter of the universe. He makes a weird assumption that the day-night solar parallax is the same as the annual stellar parallax, and also contains Aristarchus's measurement errors, yet comes to the conclusion that the universe is what we'd today call two light years in diameter.


Dr Crusher: "Computer, what are the dimensions of the known universe?"
Computer: "The known universe is a sphere, 700 metres in diameter."

And, as it turned out, the computer was right.

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Re: 1255: "Columbus"

Postby Zinho » Mon Aug 26, 2013 5:50 am UTC

NumberFourtyThree wrote:
meat.paste wrote:
dalcde wrote:C'mon, "round" is just a lazy way to say "spherical"1

1Technically speaking, ball-shaped


Really technically speaking, it's an oblate spheroid. With 3 nipples to rain milk down on the turtles holding the planet up. (It's turtles all the way down, you know.)


I remember once I saw some comic where some guy jumped off the edge of the world with a rope tied around his waist, and saw a stack of turtles, but like 4 or 5 down there was an armadillo instead, and he said "Aha! An armadillo! I knew it couldn't be turtles all the way down!" I tried a google search but couldn't find the comic and I can't remember for sure where I saw it.


I think I found it for you. That comic needs a transcriptionist, seems like it's got good content (deep archives, too, even if it ended last year), but hard to search.

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Re: 1255: "Columbus"

Postby elej » Mon Aug 26, 2013 11:05 am UTC

shokoshu wrote:Who cares about Columbus, I finally know how to get to Valinor! So obvious in hindsight!


Yay! I thought no one was going to talk about it. It would make sense though. Middle earth is suppose to be in Europe (and hobbits are still supposed to be living in modern England I believe). So that would have placed Valinor in the Atlantic Ocean (Atlantis?).

Laughed at the alt-text.

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Re: 1255: "Columbus"

Postby Klear » Mon Aug 26, 2013 1:22 pm UTC

Zinho wrote:
NumberFourtyThree wrote:
meat.paste wrote:
dalcde wrote:C'mon, "round" is just a lazy way to say "spherical"1

1Technically speaking, ball-shaped


Really technically speaking, it's an oblate spheroid. With 3 nipples to rain milk down on the turtles holding the planet up. (It's turtles all the way down, you know.)


I remember once I saw some comic where some guy jumped off the edge of the world with a rope tied around his waist, and saw a stack of turtles, but like 4 or 5 down there was an armadillo instead, and he said "Aha! An armadillo! I knew it couldn't be turtles all the way down!" I tried a google search but couldn't find the comic and I can't remember for sure where I saw it.


I think I found it for you. That comic needs a transcriptionist, seems like it's got good content (deep archives, too, even if it ended last year), but hard to search.


Oddly enough, he's jumping down from a spherical Earth...

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Re: 1255: "Columbus"

Postby wumpus » Mon Aug 26, 2013 4:43 pm UTC

da Doctah wrote:
KarenRei wrote:Archimedes once used Aristarchus's work to estimate how many grains of sand it would take to fill the universe - and, by more important side-calculation, the diameter of the universe. He makes a weird assumption that the day-night solar parallax is the same as the annual stellar parallax, and also contains Aristarchus's measurement errors, yet comes to the conclusion that the universe is what we'd today call two light years in diameter.


Dr Crusher: "Computer, what are the dimensions of the known universe?"
Computer: "The known universe is a sphere, 700 metres in diameter."

And, as it turned out, the computer was right.


They remade "for I have touched the sky"? I thought they were done with TOS remakes/revisits after the first couple of seasons (or course I didn't watch it much longer).

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Re: 1255: "Columbus"

Postby wumpus » Mon Aug 26, 2013 4:50 pm UTC

Goof wrote:In defense of Columbus: he had concrete evidence, not theory, to support his views; for example, storms had borne strange bird from the west, and the ocean had carried green logs from the west. There must be some land fairly nearby that had produced these. And that land had to be China [this was his error]. He wasn't lucky that he found land well before China — he knew it was there.

Aside: while my teachers taught that everyone else in the 15th century thought that the world is flat, schools apparently no longer do so. Progress! Next step: an official Eratosthenes Day!


I was fairly certain that Columbus vigorously defended that he (and later conquistadors) were visting Easter Asia. I certainly recall that he demanded signed copies stating that Columbus was in Asia, but googling has failed me. Even had Columbus been claiming that he was seeking a route to India, once word of gold leaked out you would think he would cop to finding a new world (especially if he was in it for the glory). Even Spanish monarchs can forgive a lot for someone who brings in the gold like Columbus.

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Wnderer
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Re: 1255: "Columbus"

Postby Wnderer » Mon Aug 26, 2013 5:30 pm UTC

640px-Atlantic_Ocean,_Toscanelli,_1474.jpg


http://en.wikipedia.org/wiki/File:Atlan ... ,_1474.jpg

This is what Columbus expected to find.

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Re: 1255: "Columbus"

Postby PM 2Ring » Mon Aug 26, 2013 5:48 pm UTC

From Wikipedia
Historians have traditionally argued that Columbus remained convinced to the very end that his journeys had been along the east coast of Asia,[91] but writer Kirkpatrick Sale argues that a document in the Book of Privileges indicates Columbus knew he found a new continent.[92] Furthermore, his journals from the third voyage call the "land of Paria" a "hitherto unknown" continent.[93]

On the other hand, his other writings continued to claim that he had reached Asia, such as a 1502 letter to Pope Alexander VI where he asserted that Cuba was the east coast of Asia.[94] He also rationalized that the new continent of South America was the "Earthly Paradise" that was located "at the end of the Orient".[93] Thus, it remains unclear what his true beliefs were.

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Re: 1255: "Columbus"

Postby moody7277 » Mon Aug 26, 2013 5:51 pm UTC

elej wrote:
shokoshu wrote:Who cares about Columbus, I finally know how to get to Valinor! So obvious in hindsight!


Yay! I thought no one was going to talk about it. It would make sense though. Middle earth is suppose to be in Europe (and hobbits are still supposed to be living in modern England I believe). So that would have placed Valinor in the Atlantic Ocean (Atlantis?).


Numenor was Atlantis. Valinor is where North America is now until it got taken Somewhere Else.
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