Basically the crust of the earth is an insulating layer protecting the surface/atmosphere from the temperature of the mantle. The generally held thoughts about how the crust formed and our atmosphere developed is that they kind of helped each other along. As one cooled so did the other and influenced each other until we got oceans which sped things up greatly to get to where we are now. But it was thought that as the first rocks of the crust formed, the atmosphere was still something akin to Venus. The Zircons they found appear look like really old subduction zone basalts. Well that would mean A) rocks that formed closer to the surface than would have been expected. Rocks that old are (If I remember right) all granitic, fairly deep in formation. B) to get geochemistry similar to subduction zone basalts according to all examples we know of you need liquid water to interact with the rock, and for the rock to re-melt, which should not have occurred due to the extreme heat of the atmosphere at the time and another ~few 100 million years.

I’m not sure but I’m thinking maybe the water was from a Comet, maybe a direct impact. The chances are next to zero for something like that, but liquid water on the surface, and a mechanism for re-melt is even more remote. It is still interesting that Crustal rocks seem to have formed a couple 100 million years prior to previously thought, and be maybe more widespread, But I think the jury is still out on the temperature of the atmosphere.

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The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.
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