Solar system discoveries

Question 1

Who was Ptolemy?

Answer 1

Claudius Ptolemy (c.90-c.168)

• Greco-Roman writer of Alexandria
• First Geocentric Model of universe.

Question 2

Who was Tyco Brahe?

Answer 2

Danish Astronomer (1546-1601)

• built observatory in Copenhagen
• Made various observations

Question 3

Who was Nicolas Copernicus?

Answer 3

Polish astronomer (1473-1543)

• First Heliocentric model of the Universe.
• Believed that the Earth and all the other Planets orbited the sun.
• 1543 on the revolutions of the Celestial Spheres (De Revolutionibus Orbium Coelestium)
• Book Published on death-bed
• Afraid of what Church would do to him.
• Retrograde motion only explainable with Heliocentric model.
• Theory only accepted in late 16th century.

Question 4

Who was Johannes Kepler?

Answer 4

• Tyco Brahe’s assistant.
• Formulated laws of planetary motion.
• 1st and 2nd laws published in New Astronomy in 1609.
• 3rd law published in Harmonies of the Word in 1619.

Question 5

Who discovered Uranus?

Answer 5

William Herschel in 1781.

• Used home-made telescope from the garden of his house in Bath.
• Had particular interest in naked eye stars.
• Initially mistook Uranus for a star
• Herschel tracked the star to find an orbit
• He was then able to work out that the object was a planet.

Question 6

Name some of Galileo Galilei’s discoveries.

Answer 6

-The moon was not spherical and contained mountains and craters
-Venus’s phases
Were exactly like the moon
-Jupiter’s four satellites
Callisto, Europa, Ganymede

Question 7

Who was Isaac Newton?

Answer 7

English physicist and mathematician (1643-1727)

• Theory of Gravity.
• Found the force of attraction on two objects in directly proportional to the product of their masses.
• Found out that the were inversely proportional to the square of the distance between them.

Question 8

Who discovered Uranus?

Answer 8

William Herschel in 1781.

• Used home-made telescope from the garden of his house in Bath.
• Had particular interest in naked eye stars.
• Initally mistook Uranus for a star
• Herschel tracked the star to find an orbit
• He was then able to work out that the object was a planet.

Question 9

Who found the Dwarf Planet Ceres?

Answer 9

Sicilian astronomer Giuseppe Piazza in 1801

• Astronomers predicted another planet in between Mars and Jupiter
• Piazza found faint star moving in position over several successive nights.
• Believed it was a new comet
• Fell ill and unable to observe it.
• Carl Friedrich Gauss and von Zach determined that this was a planet.

Question 10

Who predicted the existence of a planet beyond Uranus?

Answer 10

John Couch Adams and Urbain Le Verrier. 1846

They believed this because there were wobbles in the orbit of Uranus.

Question 11

Who found Neptune?

Answer 11

Johann Galle and Heinrick D’arrest

Based on Le Verrier’s predicted position

Question 12

Who discovered Pluto?

Answer 12

Clyde Tombaugh in 1930

Received Edward and Percival’s predictions located the planet photographically.