Replies

The Moon may have allowed life on Earth but not for the reason most people used to site (i.e., tides). I think the Moon, is important because the Moon-formation collision that is now the leading candidate for how it formed reliquified the Earth and likely contributed heavy elements, iron, and water to the young Earth. This has kept our core molten all these billions of years so we have a magnetic field. That means that unlike Venus or Mars, we aren't being directly hit by the solar wind and other radiation and crust isn't collapsing and cracking as the planet solidifies. In fact, the evidence of the other rocky planets in our solar system suggests that core solidification in the first billion or two years is the norm and Earth is unusual in that it still has a molten core and magnetic field. The Moons of Jupiter retain liquid and warmth through gravity deformation and radiation, not necessarily the most life-friendly energy sources for a world to have. Do any of the big outer moons have magnetic fields?

Well, The collision itself isn't the cause for the mantle, as I understand, the tidal forces, like a slow moving blender on the mass of the earth maintain the tasty liquid center of the earth.

Once life was established, the tidal affect also helped create a more constant dynamic of atmosphere and sea. The manipulation of the oceans, allowed for a renewal of the surface waters, as well as a significant source of oxygen dissolution within the waters. Also the tidal forces of the moon pull on ALL mass on the earth, likely we wouldn't have tectonic forces on earth to the degree we do, allowing a continuous exchange. The effect of the moon are innumerable on all things concerning life on the planet.

So I agree, but there are a LOT of things worth agreeing about when it comes to the moon being the real reason for life on earth.

I think the Moon, is important because the Moon-formation collision that is now the leading candidate for how it formed reliquified the Earth and likely contributed heavy elements, iron, and water to the young Earth. This has kept our core molten

I think the moon is important too and the moon/earth system is a billion to one chance against. Further, you are right about keeping the core liquid but maybe not for the right reason. The moon has no iron core. Most likely the iron core of the incoming object merged with earth while the lighter stuff got blasted into orbit to form the moon. This left earth with a bigger than normal core than mars or venus and this made it slower to crystallize.