Historical Observations
Main article: History of Mars observationThe history of observations of Mars is marked by the oppositions of Mars, when the planet is closest to Earth and hence is most easily visible, which occur every couple of years. Even more notable are the perihelic oppositions of Mars which occur every 15 or 17 years, and are distinguished because Mars is close to perihelion, making it even closer to Earth.
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Famous quotes containing the words historical and/or observations:
“By contrast with history, evolution is an unconscious process. Another, and perhaps a better way of putting it would be to say that evolution is a natural process, history a human one.... Insofar as we treat man as a part of nature—for instance in a biological survey of evolution—we are precisely not treating him as a historical being. As a historically developing being, he is set over against nature, both as a knower and as a doer.”
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