A Son Digresses into Outer Space

Here’s a digression, riffing off of what dad put into his last post.

For me, when I’m thinking about questions like “How did we get here?”, the ones that dad was pondering about in that last blog update, my brain shoots all the way back to the beginning. Not necessarily to the Big Bang, which I’ve heard described enough times that I’m not super interested in it anymore, but more in the history of Earth and the history of life on this planet.

(Here’s a good Big Bang primer, in case you’re not bored with it yet.)

Because the history of the planet and of life both fascinate me, partly because they seem simultaneously to be totally inevitable and completely improbable.

Digging into the history a little bit, I found Theia, which was an early planet-sized object roughly the size of Mars (they think), that had a head-on collision with Earth back before life existed. Earth was basically a sphere of boiling magma at that point, You can only imagine the planetwide shockwave that occurred after the impact.

Parts of Theia became Earth and parts of the Earth and Theia shot up into the sky, to eventually coalesce into the moon.

Amazing, right?

And they say without that impact, Earth’s core would have been lighter, which would have changed its orbit, which would have changed its whole history.

And it’s (obviously!) impossible to trace our lineage all the way back through the history of life, back through the early sapien exodus from Africa back through the tiny mammals that survived the K-T extinction back through the Cambrian explosion back to the origins of life, just a handful of simple, single-celled jobbers whose entire lives were basically chemical reactions.

And from that, we got all of this.

Here’s one of the videos that I watched that did a pretty good job. It’s long, so watch as much as you want. See you next week!