to the list of predictions
Activity of meteor showers until nowadays remains one of the most unpredictable actronomical phenomena. Scientists learned to make very detailed predictions of such events as solar and lunar eclipses, planetary transits on the Sun. The evolution of Solar system main bodies is computed for many thousand years to the past and future, for asteroids such computations are made at least for hundreds of years (the most important purpose is search for those of them which can collide with the Earth). At the same time, meteor showers, whose activity in astronomical terms occurs literally side by side to the Earth, continue to surpise us.
During many decades meteor astronomers tried to predict meteor activity using different criteria. But it was like guessing. In some cases their expectations realized, although often meteor activity anyway caused a stir in something (for example, occuring at not expected time or giving strong fireball activity). Sometimes such forecasts proved to be completely wrong.
The method of meteor activity prediction using the computation of meteor particles orbital evolution after their ejection by a comet become more widespread in 1990s. Earlier its use was restricted by low computing abilities of computers. By the end of 1990s, when computers became powerful enough, several researchers, - Robert MacNaught, David Asher and Esko Lyytinen, - published their predictions of Leonid activity for several nearest years. THe Leonid storm in 1999 became the first confidently predicted one with such method.
Of course, mainly due to the lack or inaccuracy of initial orbital elements of parent comets, as well as probable imperfections in the method itself, its reliability is still lower than desired. Serious faults in time accuracy and especially intensity of outbursts are still very typical for meteor predictions, as well as cases of their failure (the last such situation was with predicting activity of Draconids 2005). Nevertheless, it is obvious that this method is a large step forward comparing to predictions on the base of distances between the Earth orbit and orbital nodes of parent comets and times of their passage by the Earth.
Observing data allowed to build a model for calculation expected ZHR of meteor outbursts. Such a model, created by E. Lyytinen and T. van Flandern and presented in , was taken by the Author as the base for computation of expected intensity of Leonid outbursts.
The Author wishes to express his special thanks to Sergey Shanov and Sergey Dubrovsky, who provided him with their program "Comet's Dust 2.0". It is very likely, that without the program this work would be unrealizable, as the Author would then have to make very sufficient additional efforts to create an analogous algorithm for computation of meteor particles orbital evolution, without any guarantees of success.
Also I can't certainly avoid mentioning the works of other researchers in Leonid activity prediction (as well as many other showers). The Autor is familiar with predictions by E. Lyytinen and T. van Flandern for a number of years after the comet 55P perihelion in 1998 (they are given in the already mentioned paper ), wonderful grafic predictions by J. Vaubaillon (for many Leonid returns in 19-21 cc., but mainly for around 1998 and 2031 returns), predictions by David Asher ans Robert McNaught (in particular, they were the first, who point out the probable Leonid enhancements in 2006 and 2007), computations by Mikiya Sato (who helped me in coordination and precising of some predictions), and results by Isao Sato for a large number of years in 19-21 centures. This list is far not full, we beg pardon to those, who were omitted due to our ignorance or oblivion. We hope that prepared predictions will be a good addition to the results of these authors, and the reader will expand its knowledge about such a great shower as the Leonids.
Introduction 1901-1910 2001-2010 1911-1920 2011-2020 1921-1930 2021-2030 1931-1940 2031-2040 1941-1950 2041-2050 1951-1960 2051-2060 1961-1970 2061-2070 1971-1980 2071-2080 1981-1990 2081-2090 1991-2000 2091-2100 Conclusion
1. "Comet's dust 2.0" program by S. Shanov and S. Dubrovsky. [Used for orbital computations.]
2. NK 722 http://www.oaa.gr.jp/~7Eoaacs/nk/nk722.htm [Orbital elements of 55P Tempel-Tuttle].
3. Lyytinen E, van Flandern T. "Predicting the strength of Leonid outbursts", 2000, Icarus, P. 158-160.