I haven’t found anything on line about it yet, but I heard on the television today that in analyzing the Yucatan crater, they’ve determined that the impact occurred hundreds of thousands of years before the dino extinction, so the original Alverez theory may not be true.

On the other hand, much closer to home, both in distance and time, a paper presented at last week’s planetary defense conference speculates that a comet may have caused the Chicago Fire.

Well, that would let Mrs. O’Leary’s cow off the hook. Bossy may be exonerated after all these decades.

Either way, it would still be prudent to keep looking for them and to quickly develop the technological capability needed to deal with any that appear to have our number.