[Swordmaker]

Naturally, as a lunar origin via capture proponent, I don't share the view that an early-formation Mars-sized impact produced our Moon, which is (I think) your view. We also share the view that the planetary paths are not primordial.

I do... but I do not believe the capture came from a free-roaming rogue, I think it is a planet from our own system (not necessarily a "Sol" based system) that we acquired during the break up of the Saturnian System which we were once part.

For a rogue to simply fall into an Earth orbit, it would have to be traveling at a much lower speed than the stellar speeds we were talking about. The current lunar velocity is about 15,500 MPH... far slower than the 490,000 MPH Galactic orbital speed...

[SunkenCiv]

The 490K MPH is of course relative to the center, so it's not really a meaningful comparison. Obviously there's a broad range of relative velocities between the stars, and this Orionid junk has some kind of relative velocity. I'm not suggesting that the Moon came from there, only that large impactors / interlopers could indeed come from outside our system.

---

The Cycle of Cosmic Catastrophes: Flood, Fire, and Famine in the History of Civilization by Richard Firestone, Allen West, and Simon Warwick-Smith

---