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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“We can imagine a society in which no one could survive as a social being because it does not correspond to biologically determined perceptions and human social needs. For historical reasons, existing societies might have such properties, leading to various forms of pathology.”
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