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:
“What are your historical Facts; still more your biographical? Wilt thou know a Man ... by stringing-together beadrolls of what thou namest Facts?”
—Thomas Carlyle (1795–1881)
“The truth is, the Science of Nature has been already too long made only a work of the brain and the fancy: It is now high time that it should return to the plainness and soundness of observations on material and obvious things.”
—Robert Hooke (1635–1703)