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+--- Thread: Article We owe our lives to the Moon (lunar geological effects) (/thread-15174.html)
We owe our lives to the Moon (lunar geological effects) - C C - Dec 27, 2023
https://www.universetoday.com/164878/we-owe-our-lives-to-the-moon/
EXCERPTS: . . . In fact, no other planet in the solar system – or any exoplanet known orbiting other stars – has a moon quite like the Moon. With the exception of Pluto and its companion Charon, no other planet has a satellite with the relative mass of Luna. The giant worlds like Jupiter and Saturn have some moons large enough to be planets in their own right, but they are insignificant next to the massive bulk of their parents. The Moon is roughly 1% the mass of the Earth, a percentage unheard of in the galaxy.
And, as is the nature of nature, we found ourselves with our satellite through the chance encounter of a violent collision...
[...] And we’re lucky to have that faithful companion. Day to day, the Moon doesn’t largely affect the Earth...
[...] But over the long haul, when we zoom our perspective out over billions of years, the Earth wouldn’t be the same without our sole friend. Our planet spins about its axis, but that spin is tilted with respect to the movement of the Earth in orbit around the Sun by 23 and a half degrees. This tilt gives us our seasons, with half our year spent with the northern pole facing the Sun, and the other half trading places with the southern pole.
Our planet could have had any orientation it wished. The other planets have lesser and greater tilts, with Uranus tipped completely over on its side and Venus rotating backwards. And there’s nothing to keep that tilt fixed over cosmic time. Our planet was born spinning, but the internal arrangements of its core, mantle, and crust, along with the ever-present gravitational machinations of Jupiter, can cause the Earth to wobble, shifting its tilt ever so slightly.
With every shift in the tilt, the seasons would radically change. Instead of regular, predictable changes year after year, we would experience ages with endless summers, or ages with violent but short winters, or anything in between. The rhythm of the seasons provides a pulse for life, which has the freedom to grow and evolve without trying to overcome great climactic shifts caused by a changing axis.
Luna acts as a great gravitational counterweight, stabilizing the motion of the Earth. By providing a source of gravity external to our planet, the Earth’s interior is free to shift and reconfigure as it pleases – the Moon steadies our hand and keeps us upright... (MORE - missing details)
RELATED (wikipedia): Rare Earth hypothesis