[kldavis4]

> So this all had to happen sufficiently close to the Sun and that material had to be captured in the Sun's protoplanetary disc. We needed the right combination of elements to form a protective magnetic field and produce enough but not too much heat.

any idea how close? like 10s of light years or what?

[pfdietz]

Not just captured; some of the isotopes were formed in situ by bombardment of the protoplanetary disk by ~GeV range protons formed in the supernova shock by the Fermi mechanism (basically, bounce particles back and forth between moving magnetic mirrors and their energy gradually but exponentially increases.)

[MarkusQ]

According to the article, ~1 parsec, or something like 1-10 light years (further, less effect; closer, you disrupt the protoplanetary disk).