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(meteorobs) Leonids 2000-2006
Merida, February 7th, 2000
Letter To Meteorobs.
It is now clear that Asher and McNaught (1999), predicted the
time of the Leonids meteor shower with an error of only 2 minutes, a very
small value.
However it should be remembered, that just as in any x-y plot,
a prediction of a meteor shower involves two quantities, intensity and
time. The time prediction was excelent. Let us compare the predicted
intensities (ZHR) compiled in the table below.
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Authors \ Year 1999 2000 2001 2002 2006
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McNaught and Asher (1999) 500 20?to 15000 25000 100
(Letter to IMO, Nov. 9th) +1500 30?
-300
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Rao (Letter to Meteorbs, 2000to
Oct. 1999) 6000
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Isolines Method (Ferrin, A&A, 3500 5000to 400 100 20
v. 238, p. 295, 1999) +-1000 20000
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OBSERVED (Arlt et al., 3700
WGN, 27:6, p. 286, Dec. 1999) +-100
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It can be seen that the Isolines Method (IM) gave the best
prediction, suggesting that it has some predictive power. In fact IM
makes
an additional prediction not mentioned elsewhere: beguinning in the year
2000, and up perhaps to the year 2006, the Earth will enter a region with
a larger proportion of large particles. These should produce brighter
meteors. It will also reflect on the "r" value of the distribution.
The situation becomes rather interesting for the coming years.
While Asher and McNaught predict a very poor shower for 2000, with an
intensity of 20 to 30, IM predicts a very intense shower of 5000 < ZHR
< 20000, better than in 1999. I have recently revised these calculations,
with the result that the year 2000 rate may be even higher that
20.000. The only difficulty in confirming this activity is that the moon
is going to interfere with observations.
For the year 2001 and 2002, the Isolines Method predicts very
minor
showers, diminishing with the year. On the contrary Asher and McNaught
predict an intense shower in 2001 and even more intense in 2002, a very
different result.
This is good for science, because we will soon know which one of
two methods have the best predictive power. It is also good for
everybody,
because both predictions predict intense showers in the coming years!
The best is yet to come!
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