Date sent:        Fri, 12 Dec 1997 10:05:20 -0600 (CST)
Subject:          Request for feedback and information

This is a request for feedback from
a)  professionals working in the field of asteroid and comet detection, b)
those who interpret impact crater data, c) those who work professionally in
interpreting historical data related to possible impact events, and, d)
those who have published generally in the field of impacts and their

I am working on an article for Sky & Telescope on the probability of comet
or asteroid impacts on earth and rather than doing phone interviews thought
I would do this e-mail survey.

Upon hearing from you I may then establish direct contact.

1.  What is your current best estimate of the probability of asteroid/comet
impact in the future taking into account size?

2.  Can you offer comments for quotation regarding your estimates and those
of others you have seen published?

3.  Do you think the current estimates may themselves change in the future,
and if so in what manner?

4.  In view of recent budget cuts, what is your opinion about what is or is
not being done in regard to finding potentially dangerous objects?

5.  What needs to be done to rectify our shared frustration about limited
search funding?

6.  If you have the capability for performing orbit calculations and your
data indicated a possible collision event at some time t in the future, who
would you tell, beside Brian Marsden?

7.  And then what?

8.  At what size in the impact size/energy spectrum would we expect a
civilization destroying aftermath?  Civilization destroying means that the
fatalities directly caused by the impact and the subsequent breakdown of
infrastructure in the impact winter event passes a threshold beyond which
the crisis is so great that the remaining population either dies of famine
or we kill off one another in the struggle for survival.  It does not imply
the end of the species.  I have heard estimates that when we reach 20 - 25%
initial fatalities we can expect modern civilization to collapse.  What is
your best estimate of this, and why?

9. Any other ideas you wish to share pertaining to this theme, references,

Please email responses directly to me, NOT to the cambridge conference
network. My e-mail address If you were
to send attachments use -

Thank you.  This is an exercise in using the information highway to write an
article and your cooperation will be greatly appreciated.

Gerrit Verschuur

CCCMENU CCC for 1997