Viewing
Because the orbit of Mars is eccentric, its apparent magnitude at opposition from the Sun can range from −3.0 to −1.4. The minimum brightness is magnitude +1.6 when the planet is in conjunction with the Sun. Mars usually appears a distinct yellow, orange, or reddish color; the actual color of Mars is closer to butterscotch, and the redness seen is just dust in the planet's atmosphere; considering this, NASA's Spirit rover has taken pictures of a greenish-brown, mud-colored landscape with blue-grey rocks and patches of light red colored sand. When farthest away from the Earth, it is more than seven times as far from the latter as when it is closest. When least favorably positioned, it can be lost in the Sun's glare for months at a time. At its most favorable times—at 15- or 17-year intervals, and always between late July and late September—Mars shows a wealth of surface detail to a telescope. Especially noticeable, even at low magnification, are the polar ice caps.
As Mars approaches opposition, it begins a period of retrograde motion, which means it will appear to move backwards in a looping motion with respect to the background stars. The duration of this retrograde motion lasts for about 72 days, and Mars reaches its peak luminosity in the middle of this motion.
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Famous quotes containing the word viewing:
“A lover is never a completely self-reliant person viewing the world through his own eyes, but a hostage to a certain delusion. He becomes a perjurer, all his thoughts and emotions being directed with reference, not to an accurate and just appraisal of the real world but rather to the safety and exaltation of his loved one, and the madness with which he pursues her, transmogrifying his attention, blinds him like a victim.”
—Alexander Theroux (b. 1940)
“Beguile the time, and feed your knowledge
With viewing of the town.”
—William Shakespeare (1564–1616)
“Hereditary property sophisticates the mind, and the unfortunate victims to it ... swathed from their birth, seldom exert the locomotive faculty of body or mind; and, thus viewing every thing through one medium, and that a false one, they are unable to discern in what true merit and happiness consist.”
—Mary Wollstonecraft (1759–1797)