What Copernicus actually did
1.[3p] Mars returns to opposition every 779.94 days and the earth's period is 365.256 days. What is the sidereal period of Mars, in days?
Mars returns to opposition every 779.94 days and the earth's period is 365.256 days. What is the sidereal period of Mars, in days?
2.[2p] The interval between successive alignments of a planet with the sun, seen from the earth, is called its what period? One word.
The interval between successive alignments of a planet with the sun, seen from the earth, is called its what period? One word.
3.[3p] Venus reaches a maximum elongation of 46 degrees. What is its distance from the sun, in units of the earth's distance?
Venus reaches a maximum elongation of 46 degrees. What is its distance from the sun, in units of the earth's distance?
4.[3p] Mars takes 106 days to travel from opposition to quadrature. Its distance from the sun, in units of the earth's distance, is what?
Mars takes 106 days to travel from opposition to quadrature. Its distance from the sun, in units of the earth's distance, is what?
5.[2p] Copernicus's system was both simpler in the number of circles and more accurate in its predictions than Ptolemy's.
Copernicus's system was both simpler in the number of circles and more accurate in its predictions than Ptolemy's.
The answer is: False
6.[3p] In Ptolemy's models, the epicycle of every superior planet has a period of exactly one year. What does the heliocentric arrangement make of that?
In Ptolemy's models, the epicycle of every superior planet has a period of exactly one year. What does the heliocentric arrangement make of that?
The answer is: It is the earth's own orbit reflected in the sky, so the coincidence is a single fact rather than three
The answer is: It is the earth's own orbit reflected in the sky, so the coincidence is a single fact rather than three
The answer is: It is the earth's own orbit reflected in the sky, so the coincidence is a single fact rather than three
7.[2p] What did Osiander's unsigned preface tell readers of De revolutionibus?
What did Osiander's unsigned preface tell readers of De revolutionibus?
The answer is: That the hypotheses need not be true, only good enough to compute with
The answer is: That the hypotheses need not be true, only good enough to compute with
The answer is: That the hypotheses need not be true, only good enough to compute with
8.[3p] Which of these does the heliocentric arrangement determine that Ptolemy's cannot?
Which of these does the heliocentric arrangement determine that Ptolemy's cannot?
Select all that apply
The answer is: The order of the planets outwards from the centre, The distance of each planet, in units of the earth's distance, Why retrogression always coincides with the planet's greatest brightness
9.[3p] Match each observation to the heliocentric account of it.
Match each observation to the heliocentric account of it.
Mars turns back for about ten weeks
Venus never appears far from the sun
Mercury's elongation ranges from 18 to 28 degrees
The Prutenic Tables were still days out in 1563
its orbit lies inside the earth's own
its orbit departs most from a circle centred on the sun
the new arrangement improved the explanation, not the accuracy
the earth overtakes it on an inner and faster track
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Mars turns back for about ten weeks: the earth overtakes it on an inner and faster track Venus never appears far from the sun: its orbit lies inside the earth's own Mercury's elongation ranges from 18 to 28 degrees: its orbit departs most from a circle centred on the sun The Prutenic Tables were still days out in 1563: the new arrangement improved the explanation, not the accuracy