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In the Histories by Herodotus (484BC to 425BC), Herodotus recounts the story of Phoenician sailors who were dispatched by King Neco II ofEgypt (about 600BC), to sail clockwise around continental Africa, starting in the Red Sea.
The voyage took years. As they rounded the southern tip of Africa, and following a westerly course, the sailors observed the Sun as being on their right-hand side, above the northern horizon. Because they still thought the Earth was flat, the observation did not make sense at the time.
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The earliest known heliocentric theory of the solar system came from Aristarchus of Samos (310BC to 230BC). He argued that the Sun was central. He also placed all the then known planets is their correct order of distance around the Sun. His original text was unfortunately lost to history.
Nicolaus Copernicus rediscovered the theory in the 16th century. He acknowledged Aristarchus during the development of his own work.
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In one of Aristarchus' books that did survive, he laid out the earliest known attempted calculations of the sizes and distances to the Sun and Moon.
From solar eclipses, where the Moon passes in front of the Sun, they realised that the Sun was further away. Aristarchus estimated that the size of the Moon was approximately one-third that of the Earth, based on the careful timing of lunar eclipses. He was surprisingly accurate in determining the ratio of the size of the Earth to the Moon. (the Moon has a diameter 0.27 times that of Earth).
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The Antikythera Mechanism is the word's oldest surviving mechanical calculator. The device was discovered in an ancient shipwreck in 1900 and dates between the 3rd and 1st centuries BC.
When manually rotated by a handle, the gears span dials on the exterior showing the Moon's phases, the timing of lunar eclipses, and the positions of the five planets then known (Mercury, Venus, Mars, Jupiter, and Saturn) at different times of the year.
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SIMILAR ARTICLES & IDEAS:
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Human history is often framed as a series of episodes, representing sudden bursts of knowledge. The Agricultural Revolution, the Renaissance, and the Industrial Revolution are a few examples where ...
Much of the knowledge about the natural world during the middle ages dates back to the teachings of the Greeks and Romans. Many did not question these ideas, despite the many flaws.
Asteroids are what's left after the formation of our solar system from billions of years ago.
It is believed that the reason why they were formed were because of the birth of Jupiter. Its birth hindered any planetary bodies to form in the space between Mars and Jupiter, which resulted to the small objects that were present to crash onto each other and fragment themselves.
The two theories that back this up are the Nice model and the Grand Tack.
The different types of asteroids are:
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Newton’s Third Law Of Motion, which states that every action has an equal and opposite reaction is the heart of rocket science.
The basics of rocket science are not that complicate...
The thrust required for an object to overcome Earth’s gravity and atmospheric resistance and move towards space is called escape velocity. Besides Earth, the gravitational forces that can affect the object are those coming from the sun, moon and even other planets.
Apart from space vehicles and the military, rockets are used in life-saving rescue flares and fireworks, and even the ejector seats in military planes.