You can visit any reputable asteroid impact site and within a few hours at most realize that Grondine is nothing but a loony net crank after visiting his site for about 30 seconds.

Reputable information can be found at:

The Planetary Society's NEO page
http://neo.planetary.org/

http://www.boulder.swri.edu/clark/neowp.html
THE COMET/ASTEROID IMPACT HAZARD:A SYSTEMS APPROACH by Clark R. Chapman, Daniel D. Durda & Robert E. Gold (2001)

http://www.nearearthobjects.co.uk/
Report of the UK task Force on Near Earth Objects (2000)

http://impact.arc.nasa.gov/reports/neoreport/index.html
The Near-Earth Objects Survey Workgroup Report (1995)

http://impact.arc.nasa.gov/reports/spaceguard/index.html
Spaceguard Survey Report (1992)

For a good idea how little Grondine really understands impact issues see article 9 by Well Known Impact Expert Duncan Steel
"GRONDINE'S MISREPRESENTATIONS" at http://abob.libs.uga.edu/bobk/ccc/cc042401.html

See also article 7 by another well known Impact expert David Morrison RE: "SOME COMMON MISCONCEPTIONS ABOUT NASA AND NEOs" at http://abob.libs.uga.edu/bobk/ccc/cc050301.html

The comments are most amusing given Grondine has recommended both CCNet and Steel's books as reference sources.

None of the NEO task forces have made recommendations remotely similar to those at Grondine's crank website.

Many of the real experts even include their E-mail address in these messages. I used Morrisons to ask about Grondine's Lunar scope plan and he said there were far cheaper options.

You can also hear some of EP's top ten most frequent stupid comments with regard to the space program at MSNBC on the following threads:

http://bbs.msnbc.com/bbs/msnbc-space/posts/bl/115883.asp
http://bbs.msnbc.com/bbs/msnbc-space/posts/tc/115667.asp

And on the back pages here at
http://disc.server.com/discussion.cgi?id=131070&article=11809&date_query=993679053

Regards,
Mark