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:
“The past itself, as historical change continues to accelerate, has become the most surreal of subjects—making it possible ... to see a new beauty in what is vanishing.”
—Susan Sontag (b. 1933)
“The natural historian is not a fisherman who prays for cloudy days and good luck merely; but as fishing has been styled “a contemplative man’s recreation,” introducing him profitably to woods and water, so the fruit of the naturalist’s observations is not in new genera or species, but in new contemplations still, and science is only a more contemplative man’s recreation.”
—Henry David Thoreau (1817–1862)