Lunar Origins Hypotheses
Over the centuries, many scientific hypotheses have been advanced concerning the origin of Earth's Moon. One of the earliest was the so-called binary accretion model, which concluded that the Moon accreted from material in orbit around the Earth left over from its formation. Another, the fission model, was developed by George Darwin, (son of Charles Darwin) who noted that, as the Moon is gradually receding from the Earth at a rate of about 4 cm per year, so at one point in the distant past it must have been part of the Earth, but was flung outward by the momentum of Earth's then–much faster rotation. This hypothesis is also supported by the fact that the Moon's density, while less than Earth's, is about equal to that of Earth's rocky mantle, suggesting that, unlike the Earth, it lacks a dense iron core. A third hypothesis, known as the capture model, suggested that the Moon was an independently orbiting body that had been snared into orbit by Earth's gravity.
Read more about this topic: History Of Solar System Formation And Evolution Hypotheses
Famous quotes containing the words lunar, origins and/or hypotheses:
“A bird half wakened in the lunar noon
Sang halfway through its little inborn tune.”
—Robert Frost (1874–1963)
“Grown onto every inch of plate, except
Where the hinges let it move, were living things,
Barnacles, mussels, water weeds—and one
Blue bit of polished glass, glued there by time:
The origins of art.”
—Howard Moss (b. 1922)
“We shall do better to abandon the whole attempt to learn the truth ... unless we can trust to the human mind’s having such a power of guessing right that before very many hypotheses shall have been tried, intelligent guessing may be expected to lead us to one which will support all tests, leaving the vast majority of possible hypotheses unexamined.”
—Charles S. Pierce (1839–1914)