Pre-Finals Set A Flashcards
How is the universe everything?
- It includes all of space and all the matter and energy that space contains.
- It even includes time itself, and, of course, it includes you.
- Earth and the Moon are part of the universe, as are the other planets with many dozens of moons.
- Along with asteroids and comets, the planets orbit the Sun.
- All the stars in all the galaxies and all the other stuff that astronomers cannot even observe are all part of the universe.
Who perceived that the Earth was flat and had corners?
Early Babylonian, Chinese, Egyptian, and Hebrew civilizations during ancient times.
Who debunked that Earth is round and not flat?
Philosophers
the first astronomer to explain the retrograde motion of the planets in the sky.
Eudoxus of Cnidus
A Greek Mathematician who served as Aristotle’s teacher.
Eudoxus of Cnidus
designed his model of the universe as a series of cosmic spheres containing the stars, the sun, and the moon all built around the Earth at its center
Eudoxus of Cnidus
The first Geocentric model created.
By Eudoxus of Cnidus
The Sun, Moon, the planets, and the fixed stars move around in spheres that extend outward from the center.
Eudoxus of Cnidus
- The outermost sphere contains fixed stars.
- The only known planets at the time (Mercury, Venus, Mars, Jupiter, and Saturn) each have four spheres while the Sun and Moon have two.
Eudoxus of Cnidus
Greek philosopher and astronomer, considered the model proposed by Eudoxus, but he considered these spheres as physical entities.
Aristotle
defined the centric spheres as tangible entities filled with a “divine” and eternal substance called an “ether” that caused the spheres to move.
Aristotle
He also emphasized that Earth remained stationary in its place at the center, and it was spheres that spun eternally around it.
Aristotle
Introduced the concept of Prime Mover as the ultimate driver of all motion in the universe.
Aristotle
A Greek astronomer and mathematician, who made the first attempt to create a heliocentric model, which places the sun at the center of the universe.
Aristarchus of Samos
attempted to calculate the relative distance between the Earth and the Sun
Aristarchus of Samos
said that smaller celestial bodies must orbit the larger ones and since the Sun is much larger than the Earth, then the Earth must orbit around the Sun.
Aristarchus of Samos
In his model called the heliocentric model, the Moon, the Earth, and the then-known five planets revolved around the Sun in different sizes of orbits at different speeds.
Aristarchus of Samos
what year was Claudius Ptemaeus (Ptolemy) born?
born c. 90 A.D
a Greco-Egyptian astronomer and mathematician who proposed his own geocentric model of the universe.
Claudius Ptemaeus (Ptolemy)
He accounted for the apparent motions of the planets around the Earth by assuming that each planet moved around a sphere called an epicycle.
Claudius Ptemaeus (Ptolemy)
The center of the epicycle then moved on a larger sphere
deferent
introduced the concepts of epicycle, deferent, and equant to explain the observed “imperfect” motions of the planets.
Ptolemaic model (by Ptolemy)