How the Greeks Knew the Earth was a Sphere


‘As long ago as 340 BC the Greek philosopher Aristotle, in his book On the Heavens,
was able to put forward two good arguments for believing that the earth was a round sphere rather than a Hat plate. First, he realized that eclipses of the moon were caused by the earth coming between the sun and the moon. The earth’s shadow on the moon was always round, which would be true only if the earth was spherical. If the earth had been a flat disk, the shadow would have been elongated and elliptical, unless the eclipse always occurred at a time when the sun was directly under the center of the disk. Second, the Greeks knew from their travels that the North Star appeared lower in the sky when viewed in the south than it did in more northerly regions. (Since the North Star lies over the North Pole, it appears to be directly above an observer at the North Pole, but to someone looking from the equator, it appears to lie just at the horizon. From the difference in the apparent position of the North Star in Egypt and Greece, Aristotle even quoted an estimate that the distance around the earth was 400,000 stadia. It is not known exactly what length a stadium was, but it may have been about 200 yards, which would make Aristotle’s estimate about twice the currently accepted figure. The Greeks even had a third argument that the earth must be round, for why else does one first see the sails of a ship coming over the horizon, and only later see the hull?’

– Hawking. S. (1998) A Brief History of Time New York, United States: Bantam Books p. 2

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Death of the Dinosaurs


The fifth extinction
65 million years ago

Boom. Extinction. 65 million years ago, a huge chunk of rock from outer space smashed into what is now Mexico. The explosion was devastating, but the longer-term effects were worse. Dust was thrown into the upper atmosphere and blocked out sunlight, and in the ensuing cold and darkness Earth suffered its fifth and last mass extinction. The dinosaurs were the most famous casualties, but pterosaurs and giant marine reptiles were also wiped out.

See other: History of Life

Conversations: Arrogant Scientists?


Helena
As many critics of religion have pointed out, the notion of a creator poses an immediate problem of an infinite regress. If God created the universe, what created God?

Galene
The God of most monotheists is believed to be an uncreated entity.

Sappho
To say that God, by definition, is uncreated simply begs the question. The truth is that no one knows how or why the universe came into being. It is not clear that we can even speak coherently about the creation of the universe, given that such an event can be conceived only with reference to time, and here we are talking about the birth of space-time itself.

Helena
The physicist Stephen Hawking, for instance, pictures space-time as a four dimensional, closed manifold, without beginning or end (much like the surface of a sphere). Having said that, any intellectually honest person will admit that he does not know why the universe exists. Scientists, of course, readily admit their ignorance on this point. Religious believers do not. Continue reading

On the Closed Universe


“The universe is like a safe to which there is a combination, but the combination is locked in the safe.”

– Peter de Vries

Conversations: Civilization of Ignorance


Sappho
All complex life on earth has developed from simpler life forms over billions of years. This is a fact that no longer admits of intelligent dispute. If you doubt that human beings evolved from prior species, you may as well doubt that the sun is a star.

Galene
Well, not to be facetious, but the sun doesn’t look like any other star.

Sappho
Granted, the sun doesn’t seem like an ordinary star, but we know that it is a star that just happens to be relatively close to the earth.

Helena
The point is this: imagine your potential for embarrassment if your religious faith rested on the presumption that the sun was not a star at all. Imagine millions of Christians in the United States spending hundreds of millions of dollars each year to battle the godless astronomers and astrophysicists on this point. Imagine them working passionately to get their unfounded notions about the sun taught in our nation’s schools. This is exactly the situation Christians are now in with respect to evolution. Continue reading

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Almost any domestic cat can run faster than Usain Bolt.

According to a 2015 poll conducted by Public Policy Polling, 30% of Republicans polled in favour of bombing the fictional city of Agrabah, featured in Disney’s Aladdin (1992).

Kali is the Hindu goddess of death, violence, sexuality and, motherly love.

In 2015, there were more days with a mass shooting than days without a mass shooting in the United States.

The Moon has earthquakes that last for up to 10 minutes. Because the Moon is so dry and dense, they earthquakes it vibrate like a tuning fork.

See other: Quite Interesting Facts