At 09:33 AM 2/26/2003 -0800, David Morrison wrote: >Colleagues: > >This is a follow-up to my note yesterday about the non-statistical nature >of an asteroid search carried out for the purposes of planetary defense. >You may be interested in the following "sound bite" statements that I have >found can help to make these and related points. (Reactions are welcome, >especially if you don't agree with any of these statements.) Just a couple to comment on: >A large country (like Russia, China, USA) is more likely to be hit, but >its citizens are no more at risk than those of a small country. I would clarify "its citizens individually are..." >We have a choice: Deal with the small impacts that hit more frequently but >pose very low risk, or deal with the large ones that are infrequent but >are more likely to kill you. (The current Spaceguard Survey deals with the >large ones that pose the greatest risk) With the technology at hand (optical surveys), we actually don't have a free choice: by the very nature of the survey, we deal with the largest ones first. Even a highly capable survey like LSST finds the biggest ones fastest, whether you want to or not. It is just a lucky (?) coincidence that it is the largest, and thus easiest to discover, objects that pose the greatest hazard. Even if that were not true, we would still find the biggest ones first. It is really quite unrelated to priorities. That's the point o capture in a "sound bite" >Impacts are the only known natural hazard that could destroy civilization. I would question this. We see evidence of volcanism of far vaster proportions than anything we have experienced in historical times. Thus I think it is entirely plausible that a really massive volcanic event could bring down a civilization. If you include disease as a natural disaster, one could imagine an epidemic of something as deadly as AIDS and as contagious as the flu could bring down civilization, or even cause an extinction. ******************************************************************* Alan W. Harris Senior Research Scientist Space Science Institute 4603 Orange Knoll Ave. Phone: 818-790-8291 La Canada, CA 91011-3364 email: harrisaw@colorado.edu ******************************************************************* LSST LSST LSST LSST LSST Mailing List Server LSST LSST LSST LSST LSST LSST LSST LSST This is message 81 in the lsst-general archive, URL LSST http://www.astro.princeton.edu/~dss/LSST/lsst-general/msg.81.html LSST http://www.astro.princeton.edu/cgi-bin/LSSTmailinglists.pl/show_subscription?list=lsst-general LSST The index is at http://www.astro.princeton.edu/~dss/LSST/lsst-general/INDEX.html LSST To join/leave the list, send mail to lsst-request@astro.princeton.edu LSST To post a message, mail it to lsst-general@astro.princeton.edu LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST LSST