Apparently some, at least one, thinks so, if this site is to be believed:
COMET IMPACT PREDICTIONS.
But, since it appears to use fragments from the Holy Bible, postulates about space aliens, bible codes, psychic mediums, Nostradamus and Nostradamus-like prophecies, and other droolworthy claims to support the hypothesis, believing the site just isn't very easy for anyone skeptical in the slightest degree.
Have you run into better evidence for a 1500-year period? Where did you get the value of 1500 years?