[Rockhounds] Terraforming Mars might be impossible? for now

[Alan Silverstein]

> I missed the that sf story you refer to Alan, I'll have to see if I
> can find it.

I just did a little hunting but no joy, although there's an amazing
Wikipedia cluster of pages around fiction involving asteroids!  I
vaguely recall maybe it had something to do with getting one asteroid
into Earth orbit to capture (internally) a small black hole that had
dropped into the planet and was orbiting through it, wreaking havoc.

I did find this webpage about "asteroid billiards", albeit not the same
core concept:

  https://www.space.com/41592-asteroid-billiards-smashing-dangerous-space-rocks.html

You got me hunting further, and...  Aha!  Maybe it was "The Doomsday
Effect", 1986, by Thomas T Thomas; although I can't prove it's the right
one from the abstract, nor from the Amazon free-view pages (early in the
story).

Cheers,
Alan Silverstein