The creator's hand

Back in 2011, I am now told, the solar oxygen was measured and found to differ from the oxygen found on Mars, the Moon, Earth, and maybe what's streaming back from Venus. The solution: an ultraviolet surge when the rocky planets were formed. New problem: whence?

The sun was weaker earlier on, not stronger (usually). The inner planets' orbits have changed a bit (the further in, the more an adjustment matters, at the inverse-square principle) but all that much. The Sun's T Tauri stage could explain some of it but, it seems, not enough of it.

From 1990, enter the meteorite Acfer 094. This was born "4.6" Bya by which I think they mean it's the milestone that marks our whole solar-system 4567 Mya. It still has symplectite, a mix of iron rusts, both oxygen and sulfate.

So now they measured the sulfur isotopes. This shows the UV radiation from deep space. It cannot have been solar. It was an O and B star near enough it shone like the full moon.

First off, lucky for us this solar-system ducked out before that monster went Type II. I am pretty sure we'd have a record of a supernova like that in Acfer 094. Tho' I think we'd like more meteorites like it, to make that call.

Also, I wonder if having this much energy beamed at us in our first years had some effect on drying out our inner system. Mercury was the Sun's b!tch, sure. Further out, though, Venus is famously hydrogen-poor and even the hydrogen in Earth's mantle came from comets, plastic meteors, and Theia. The inner planets lost so many lighter gases up front that we stayed, also, less massive and weren't swimming in hydrogen treacle. So they didn't migrate further in, becoming those super-Earths seen in almost every other system.