Gravity and Van Allen Belt
I think that there's a lot more favourable about Earth's environment:
* It has a moon, so a stable tilt, seasons, and tides.
* It has enough gravity to retain an atmosphere, all the gas and water will just escape into space, and an ozone layer significantly reduces the UV, so that life isn't burnt away on the surface.
* It has a large enough magnetic core and stable enough rotation, to cause a strong enough magnetic field, thus the Van Allen Belt, which shields against most of the hard solar and interstellar radiation.
Biting the hand that feeds IT
