Read
comment #329.
Mostly I wanted to know how much "SPREAD" Ison's fragments would need to be a danger to Earth.
Your
"quick off-the-top-of-the-head-estimate of about 37 MILLION miles" is what I thought, too.
Now how much of an angle from the back side of the Sun or before the backside of the Sun, during Isons breakup, would that distance require in the scattering of the "V" debris ?
But I haven't had time to work on it, yet.