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Erasmus+: Key action 2:Strategic Partnerships in School Education

Practical Exercise 2: MARS IN OPPOSITION AND QUADRATURE

How far is Mars from the Earth if Mars is in a) opposition, b) quadrature? How many times would Mars appear to be larger in opposition than in quadrature in an astronomical telescope? ahe radius of the circular orbit of Mars is a♂ = 1,52 au. Figure 1 can help.

(source: https://www.nasa.gov/multimedia/imagegallery/image_feature_329.html)

Answer:

a) From Figure 1 it is possible to easily determine the distance of the Earth from Mars in opposition:

b) ahe distance of the Earth from Mars in quadrature is determined from Pythagoras theorem:

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ahe image in the telescope will appear in opposition as many times larger than in quadrature, as the number of times Mars is closer in opposition than in quadrature:

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