"JXStern" wrote in message
...
On Sun, 22 Feb 2004 22:58:21 GMT, wrote:
I have a question.

We would probably get some warning about a comet or an asteroid - but
what
about a pea size black hole? If one hit the moon would it be like a
match
to paper and suck the entire moon into itself even if it took some time?
Could an invisible small black hole just show up over the Sierra Nevada
and
no one would have foreseen it and it would destroy the earth? Would it
destroy the earth instantly or would there be some fantastically horrible
slow whirlpool of matter into a small black hole so that we would all
have
time to feel intense fear?

I suspect these questions have been answered many times before but I
have
been looking for several months and I bet other's are wondering too.

Based on my long reading of pseudo-technical sci-fi, I have to opine
that none of this is likely to happen. The only way you'd get most of
these effects is if the black hole arrived at very slow speeds. At
even asteroid speeds of 30k km/hour, even if it hit head-on, it would
pass through the Earth and out the other side in fifteen minutes, a
few million tons heavier perhaps, but we'd never miss them.
Relatively little transfer of momentum. At the higher speeds that
galactic arrival suggests, even less effect. It'd be like shooting a
bullet through a chocolate cake, the bullet wouldn't even "see" the
target. Not that I've spent a lot of time shooting bullets through
chocolate cakes.

Try reading "The Forge of God" by Greg Bear for amusement and what I
take to be reasonably accurate speculations. Also the short story
"The Hole Man" by Larry Niven, in the collection "A Hole In Space."

J.


This are good leads. Thx