🚀 go-pugleaf

  > From: dietz@cs.rochester.edu (Paul Dietz)
  >
  > Science (10/16/92, page 403), reports that Gehrels and colleagues in
  > the Spacewatch program have detected 8 very near earth asteroids over
  > the last two years with sizes from 5 to 100 meters ... This figure is 
  > some 100 times larger than had been inferred from observations of the 
  > number of larger bodies.

That result is controversial, since it depends on statistics of small 
numbers (though not as small as they were, and rapidly growing), plus 
large corrections for selection effects.  However David Rabinowitz of 
Gehrels' group defended it stoutly at the DPS meeting a couple of weeks
ago.  As to what they are compositionally, let's not guess, let's look
at them!  Unfortunately that takes fairly ready access to a large telescope,
which few people have.

Also, someone at the DPS suggested that the Tunguska event was caused by 
the pressure-induced explosion of a a stony object, not a comet.  I believe
his main point was that an icy body would have exploded high in the 
atmosphere, and the Tunguska explosion was low.  Stony meteorites often
do make strewn-fields, whereas irons come down intact.  He didn't say
where the Tunguska fragments might be, but I suppose they could be widely
scattered and hard to find in a remote, heavily forested location, and
some of them can weather away rather quickly.

Ben