History of Astronomy - Part 3 Trivia Quiz

Answer: He believed that the Earth revolved around the sun

Much like Plato, Aristotle promoted the concept of a geocentric solar system, with the planets held in place by a series of concentric spheres. Like the Pythagoreans, and his master Plato, Aristotle endorsed the concept that the Earth was spherical, but it certainly did not revolve around the sun. Aristotle's book of astronomical theory was called 'On the Heavens' (De Caelo). Most of the Aristotelian cosmological program was adopted by Ptolemy in the 2nd century A.D.

Answer: The Earth revolves around its own axis

Heracleides (c. 390 - c. 322 BC) contradicted conventional wisdom by announcing his theory that the Earth rotated about its own axis, directly contradicting the Platonic/Aristotelian notion that the Earth was fixed in position. Heracleides further blasphemed against the general intellectual trends of the day by suggesting that Venus and Mercury revolved around the sun.

Heracleides never quite advanced his theory to the point of entirely rejecting the geocentric conception of the universe.

Answer: He was the first astronomer to advance a heliocentric conception of the solar system

Aristarchus of Samos was, along with Hipparchus, the greatest of the ancient Greek astronomers. Through the use of scientific observation, he developed his sun-centered conception of the solar system about 1,800 years before Copernicus in 270 B.C.E. Because of this, Aristarchus is sometimes referred to as the 'Copernicus of Antiquity'.

Unfortunately, most intellects of the time scoffed at the notion that the Earth did not rest in the center of the universe, and in fact Aristarchus was threatened with charges of impiety for his stated observations.

Answer: Distance from the Earth to the sun

Remarkably, Aristarchus made this measurement (the distance from the Earth to the sun) using only his naked eye. His technique was sound, measuring the angle from the moon to the sun in the night sky to attain the distance of the sun to the Earth. However, Aristarchus miscalculated the angle by about 2.5 degrees resulting in a vast error in his final measurement (he predicted that the sun was 19 times as distant to the Earth as the moon; the actual measure is about 397 times). Nonetheless, this effort, along with relatively accurate efforts in measuring the diameter of the moon and its distance from the Earth helped spur even more astronomical curiosity.

His influence on ancient astronomy must not be underestimated, despite the lack of belief in his heliocentric system.

Answer: Eratosthenes

Some consider Eratosthenes (c. 276 - c. 194 B.C.E.) to be the greatest of ancient scientists. His contribution to astronomy came mainly with his geometric calculations resulting in rather accurate measurements of the Earth's circumference and diameter. Eratosthenes was also a notable mathematician and geographer, and was the third librarian of the great library in Alexandria. Like Empedocles, Eratosthenes was flamboyant and rather vain.

After losing his eyesight at an elderly age, he committed suicide by starving himself to death.

Answer: Chinese

The Chinese were full active in recording stellar phenomena well into the 2nd millenium B.C. The Chinese recording of Halley's comet comes fully 1700 years before German scientist Johannes Müller von Königsberg, aka Regiomontanus, made the first scientific recording of the comet in the Western world. Halley's comet is also observed on the Bayeux Tapestry, which documents events of 1066 A.D.

Answer: Astrolabe

While the sextant and octant weren't developed until the 17th century A.D. (and the orrery not until the 18th century), the astrolabe is an navigational instrument of ancient origins. The astrolabe was used to calculate latitude by use of the relative positions of the stars in the sky.

This marriage of astronomy with navigation allowed for much more accurate seafaring in the ancient world. Some attribute the invention of the astrolabe to the great Hipparchus, though there is no proof that the instrument was of his design.

Answer: Rhodes

Hipparchus helped erect the great observatory at Rhodes c. 150 B.C.E. There he made his incredibly detailed observations of the night sky, which he, in turn, recorded in his now-famous catalogue of 850 stars. This star catalogue was the most complete and detailed such document of ancient times. Hipparchus lived from c. 190 to c. 120 B.C.E., dying at Rhodes.

Answer: The nature of the sun's light and heat

Hipparchus was a very busy man, not limiting himself merely to the study of astronomy. He also involved himself with geometry and geography, and has been given the title 'Father of Trigonometry' for his extensive work in that field. His best contributions to science arguably came in astronomy, however, in particular his accurate measure of the precession of the equinoxes and his theory of the motion of planets, which led to accurate predictions of eclipses.

Answer: Seleucis

Seleucis of Seleucia, who flourished around 150 B.C.E., was the greatest champion of Aristarchus' sun-centered theory in the ancient Greek world. Unfortunately, he failed to win over a still skeptical public, including most scientists of the time that continued to dream of an Earth-centered cosmological scheme. Seleucis' greatest contribution to astronomy was his correct prediction that the tidal cycle was related to the relative position of the moon and the Earth.

Thank you for having tried this quiz. I hope you enjoyed it and will try the others in this series (not to mention some of my other quizzes).