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:
“Some minds are as little logical or argumentative as nature; they can offer no reason or “guess,” but they exhibit the solemn and incontrovertible fact. If a historical question arises, they cause the tombs to be opened. Their silent and practical logic convinces the reason and the understanding at the same time. Of such sort is always the only pertinent question and the only satisfactory reply.”
—Henry David Thoreau (1817–1862)
“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)