Lew & Karen's Home Page

What is meteorobs?

Email Access to meteorobs

History of meteorobs

Search meteorobs Archive...

Browse Archive by Month...

Frequently Asked Questions

Meteor-Related Links

How to View Meteor Showers

METEOR STORMS (Leonids etc.)

Going Deeper: Telescopic Meteors


+ What are meteor showers? + What is a meteor STORM? + How can I learn more? + ... about the Leonids? + ... a small outburst in 2006? + ... about Lunar Impacts? + Observation of Leonids + The Leonids Perform for Humanity!


What are meteor showers?

Meteor showers are annual events where more meteors than usual can be seen over a given period of nights, all appearing to point back to (or "radiate from") a particular point in the sky. Among the best known annual meteor showers are the Perseids (in August), the Geminids (in December), and the Leonids (in November). For more on how to see these "everyday" meteor events, see How to View Meteor Showers.

These meteor showers actually occur when the earth in its orbit around the sun, is passing through a particular band or "stream" of meteoroid dust particles: these meteoroid streams are usually the debris trails of periodic comets, or in some cases (i.e., the Geminids) asteroids. To try to visualize these meteoroid streams, imagine the Earth having to wade a "river of dust" every 12 months: this "river" is the meteoroid stream, and the debris which strikes Earth causes what we call a "meteor shower"!


What is a meteor STORM?

On rare occasions though, Earth passes through a particularly thick clump within a meteor stream, and a meteor outburst will occur - a time when even more meteors than usual can be seen. And if these outbursts are VERY heavy, they become what are called meteor storms: a brief period of a few minutes or hours, where (from certain parts of the Earth's surface) an incredible show of falling stars can be seen.

Meteor storms are both extremely rare (once in decades) and extremely hard to predict. However, they can be life-changing events to witness (and in fact, a number of religious movements have been spawned by historic meteor storms, e.g., the Transcendentalist and Methodist Reform movements born soon after Nineteenth Century Leonid storms!) During a meteor storm, the sky seems to literally "fill with falling fire", and as many as 10 or more falling stars can be seen during a single SECOND of observing!

Finally, on many occasions hopeful watchers are given the opportunity to see not a full-blown storm of meteor activity, but rather a significant, very noticeable enhancement over normal meteor activity. Such enhanced-activity events are generally termed meteor shower outburst. Note that unlike a "storm", which is always an exciting event, "outburst" are merely a relative enhancement: if a meteor shower is normally strong, like the Perseids of August or Leonids of November, then an outburst may very well approach - but not reach - the intensity of a meteor storm. If however a shower is normally a weaker event, for example the Ursids of late December, then its "outburst" may be only noticeable as a significant enhancement to careful meteor watchers, who are used to observing meteors in general and that shower in particular.


How can I learn more?

To learn more about the best-kept secret of amateur astronomy - meteor observing - check out the following site, for the "North American Meteor Network". NAMN is a small, friendly organization which provides excellent introductory materials (for people in ALL areas of the Globe) on amateur meteor observing for fun and Science:

North American observers will also wish to peruse the American Meteor Society's fact-filled pages about meteor observing, fireballs, radio meteors and other topics, at:


How can I learn more about the Leonids?

Here is a set of other sites providing much more detail about the theory of meteor storms, the realistic prospects for seeing an outburst from the Leonids, and how to record such an outburst if it occurs again in 2006!

First, Cathy Hall of the North American Meteor Network in 2002 wrote an excellent article, "Leonids - Your Planning Guide" for the November 2002 issue of "NAMN Notes"! http://www.namnmeteors.org/namnnotes0211.html


NASA's Marshall Space Flight Center has devoted considerable resources to tracking Leonid storm predictions over the past five years. Here is a summary from the MSFC, of predictions from the three most prominent scientific teams trying to predict what the Leonids would do in 2002:


For up to date predictions by one scientist, plus additional scientific information on the various models and predictions of Leonid outbursts in the recent past, including the Leonid Storm of 1999, read Dr. Peter Jenniskens' informational site, hosted by NASA at:

Dr. Jenniskens' site at NASA provides an online "Rate Estimator", allowing you to compare predicted Leonid meteor rates with actual rates as seen from your favorite observing site in past years:

For another perspective on the exciting science of predicting meteor shower outbursts, as well as how amateurs like you can help to verify and refine those predictions, see the Leonid pages of the renowned scientists Dr. David Asher and Dr. Rob McNaught, hosted on the Armaugh Observatory Web-site:

And in particular, here is their page which gives the (unique, so far as I am aware) prediction of a possible Leonid outburst in 2006:

One of the two scientists who have developed this particular set of successful models, Dr. Rob McNaught, has also written an information sheet for amateurs, about meteor storms and the Leonids:

Also here is a less-publicized addition to the complex "game" of prediction meteor storms. Drs. Jérémie Vaubaillon and Francois Colas of the Paris Observatory lab which was once known as the Bureau des Longitudes (http://www.imcce.fr), with the support of the French Space Agency (CNES), have produced a predictive stream model, and published details and results on the Web at:

And here is the same predictions page, IN FRENCH:


Finally, another scientific team who have had success in predicting Leonid storms in recent years, are Dr. Esko Lyytinen (aided by Markku Nissinen) of Finland, and Dr. Tom Van Flandern of the USA:

You can learn more about the Lyytinen-Van Flandern scientific model and its predictions, by reading the paper at the following site:


The renowned Japanese amateur visual and radio meteor observer Hiroshi Ogawa has compiled a single set of graphs, which attempt to take into account ALL of the Leonid available predictions, as well as viewing conditions around the world!


For those interested in comparing notes on their own observing campaigns to see the Great Leonid Storm of 2001, in particular, the LEO2001 mailing list and archive will be of interest:

Gary Kronk's wonderful "Annual Meteor Shower Calendar" provides a guide to watching many of the major, minor, and periodic showers which can occur each year:

To learn much more from Gary's site about watching the Leonid shower in particular, look under "November" in the Calendar:

How did the theoreticians do with their predictions for the great Leonids of 2001? Well, the Internation Meteor Organization (IMO), an independent amateur scientific body, has published a preliminary Analysis of the 2001 Leonid Storms.

In addition, the International Meteor Organization has put together a very well organized set of pages called "2002 Leonids - Observe the meteor storm!" (Mirror page here.)

I also highly recommend reading the IMO's "Hints for Observing the 1998 Leonids", which actually provides many excellent pointers to prepare observers for recording any possible outburst display! (Mirror page here.)


Well known American meteorologist and amateur meteor science author Joe Rao has put together an entire site dedicated to what Joe calls the "King of the Meteor Showers" - the Leonids:

Or you may wish to browse the very popular and informative Sky & Telescope Meteor Pages.

More basic information from Sky & Telescope is available here:

While a more advanced "S&T" guide to meteor observing is here:


Finally, a research known for his work in "catastrophe" theory (e.g., asteroid and comet impacts), Michael Paine, has put together his own list of "Leonid Links", with emphasis on the (putative) threat to communications and other satellites in Earth orbit:


Lastly, for French speakers ONLY, the following site has been compiled to "spread the word" about the Leonids among the Francophone world:


Observing Lunar Leonid Impacts

For an interesting observing project for those equipped with tracking telescopes and video cameras, here is a page about a little publicized phenomenon which may be observable during the 2001 Leonids:
Predictions for Lunar Leonid Impacts - 2001


Past Leonid Observations from around the World

If you want to review the whole breadth of Leonid meteor observations from all over the planet the last few years, you'll find continuous records of visual, video, radio and photographic observations by amateurs and professionals, indexed at the main 'meteorobs' mailing list site:

1998, 1999, 2000, 2001, 2002: The Leonids Perform for Humanity!

(What follows is a brief personal summary of the recent history of outbursts from the Leonids... The Webmaster/Author hopes you find it enjoyable, to either reminisce with him about previous apparitions of the great shower, or to read about those events of recent history maybe for the first time...)

Coming up to November 2001's Leonid meteor shower, scientists and amateurs had been building up their expectations for three years running: First, in 1998 the predictions for the Leonids had been carefully guarded and highly uncertain. Of course, no storms from the Leonids were seen in 1998. And yet the "King of Meteor Showers" provided observers around the entire globe with one of the most incredible showers of fireballs (meteors brighter than the planets) in living memory!

(The 1998 Leonids produced an extraordinary and generally unexpected display of fireballs lasting over 24 hours... There was no "storm" of fainter meteors as predicted, though some analyses suggested that the "storm component" of smaller particles could in fact be detected in data from Central China and Mongolia! See the IMO Web site for a detailed summary of this analysis. Mirror page here.)

After these (limited) successes and the attention they generated, models were refined with the data collected by both amateurs and professionals in 1998. As a result, predictions coming into the 1999 shower began to sound increasingly precise, and increasingly confident. Never before in the Twentieth Century had expectations for a meteor display among observers and the public been so high!

And amazingly, the Leonids lived up to their reputation - and to some of the predictions of several key "dust trail" models - once again in 1999! The IMO site again published the results of that year's analysis, trumpeting a good deal more confidence in the success of 1999's batch of predictive models. Mirror page here.

However, unlike in 1998, the really breathtaking displays of 1999 were reserved for only a certain narrow part of the earth's surface - just five time zones. This caused many casual observers - particularly in the US - to erroneously refer to this incredible year as a "dud" for the Leonids. Yet for those few in lucky longitudes, the display in 1999 was orders of magnitude more intense than 1998: To get an idea what it felt like to actually SEE the meteor storm of 17/18 November 1999, listen to this audio sample from an actual recorded observing session that night.

Well needless to say, once again in 2000 the Leonids came through for humanity! Although they did not produce a true storm as seen from anywhere on earth, they did produce a wonderful and very rare outburst of activity, and that year the fun could be experienced for those in the latitudes of Western Europe and the Eastern United States! Gary Kronk, within his delightful "Meteor Observing Calendar", has an excellent Summary of Leonid 2000 Results.

And how about the 2001 Leonids: Well, as one of the observers privileged to see the "Asian Storm", one of two paired meteor storms which blessed humanity around the globe in 2001 , this author can resoundingly and truthfully say, "Yes! The Lion once again reigned supreme in the fated year of 2001!"

The year 2002 was a bittersweet one: Many observers in Europe, and much of North America, had the opportunity to enjoy a "farewell"(?) outburst. For this observer, sadly, conditions conspired in the New England States of the USA, such that he JUST MISSED this last in the great string of Leonid meteor events. Still, I was heartened recently to read that Messrs. Asher & McNaught have a tentative prediction for one last (small) outburst of the Leonids in 2006.

This shower was generally considered to be a "weak member" of the "Major Shower Calendar" back in the 1970s and 1980s. Yet now for five years running, it has produced displays that exceed those of any other annual meteor shower, either in brightness or in the sheer number of meteors to be seen. Will 2006 be a final, farewell year of an incredible run of luck for meteor observers and scientists? Why not watch with your fellow meteor watchers worldwide and find out!

If you are interested in subscribing to the 'meteorobs' mailing list, you may use the MeteorObs Subscription Web form now! Otherwise, you may post a (moderated) question to the list even if you are not a subscriber.
Clear skies!
Lew Gramer <dedalus@alum.mit.edu>