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Speculation? No problem.

The near-Earth-asteroid Itokawa comes around during the Sagittarid meteor shower. Link and info from there are below. This is no big surprise, there are meteor showers of impressive to *yawn* pretty much all the time. Itokawa was bound to occur regularly at the same time as _some_ meteor shower or other.

Meteor showers are the left over solids from a comet that has lost all of its ice. This debris is in roughly the same orbit as the comet, but because it is mostly small stuff it is affected by the solar wind and gravity of bodies it passes and gradually spreads out, but still pretty much along that orbital path. The densest part of the debris is where the last leftovers of the comet head are still clumped and haven't spread out evenly yet.

_If_ Itokawa is an unusually large chunk from the comet head that created the Sagittarids, it might mark the dense part of the debris field. The Sagittarids are associated with fireballs, so there's larger stuff than just sand and dust in that orbit.

Itokawa has come closer than 0.1 AU on six occasions in the last century. Three times those close passes where from the north well before we entered the meteor stream. Three times it was near while we were in the meteor stream. One of those times was when the Tungusta explosion occurred.

Itokawa is approaching and will be at its closest on June 26. We've already had several reports of fireballs. Are we in a window of high risk?

http://snegazers.brainiac.com/snegazers/archive/0203/msg00052.html

"The Sagittarids (SAG) start to appear about April 15th, and will last until about mid-July. This is a complex of radiants near the ecliptic, and is believed to be the debris from a number of unknown bodies. Fireballs have
been associated with this shower. On April 20th, the Sagittarid radiant will be at 227 degrees, ie RA 15h 7.8m, Dec -18, which is about 7 degrees north of the star sigma Libra. These meteors are almost slow, with a velocity of about 30 km per second, and the ZHR rates are about 5 meteors per hour."

MataPam
Ooo! First post here (long term lurker) and I got to lecture!