2012-06-18

The Moon

Watching some of these science shows that Jenn comes up with on the PVR leads to some interesting thoughts.

For example: maybe one of the most important components in a planetary system that will spontaneously start to support life is: a large, single, moon.

Here's what I'm thinking:

  • Life on Earth is dependent on the infusion of complex elements and molecules, formed in the core, and probably started in the ocean depths where those elements and molecules are brought together under great pressure near undersea volcanoes -- the subduction and induction zones caused by continental drift.
  • Continental drift may be partially enabled by the constant tidal kneading of the crust by the moon's gravitational force as it orbits.
  • The crust on the Earth is much younger than it would have been had the Mars-sized object not collided with it 4.5 billion years ago, a collision which formed the Moon.
  • Life on Earth is protected from solar radiation by a strong magnetosphere, generated by the rotation of the molten core, rotation which probably received a whole whack of energy in the collision which formed the Moon.
Put together, it argues for Europa being another credible site of life formation -- at least on the primitive level -- deep pressures, water, and potential volcanoes caused by tidal forces from Jupiter.

Here's more: a video that shows how the Earth's magnetosphere helps protect the planet from coronal mass ejection (CME) events.  But relevant to this discussion is the observation that CME events have pretty much stripped any free water away from Venus, making life there unlikely, at least in the way that we understand.  The take-away from that: Venus doesn't have a magnetosphere, which to me means that either Venus' core isn't spinning the way Earth's is, or that Venus' core has a significantly different composition.  And looking at the topography, there isn't clear evidence of specific volcanic activity, or plate tectonics in general.