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# Posted: 16 Nov 2006 02:21
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The annual Leonid meteor shower could produce a strong outburst this weekend for residents of eastern North America and Western Europe.
A brief surge of activity is expected begin around 11:45 p.m. ET Saturday, Nov. 18. In Europe, that corresponds to early Sunday morning, Nov. 19 at 4:45 GMT. The outburst could last up to two hours. As always though with Meteor storms, activity can be witnessed hours before a "peak". So, if you don't fancy staying up late, just get out on the night of the storm and see what you can see. 
At the peak, people in these favorable locations could see up to 150 shooting stars per hour, or more than two per minute.
"We expect an outburst of more than 100 Leonids per hour," said Bill Cooke, the head of NASA's Meteoroid Environment Office. Cooke notes that the shooting stars during this peak period are likely to be faint, however, created by very small meteoroid grains.
Elsewhere people will see the typically enjoyable Leonid display of a few meteors each hour, weather permitting and assuming dark skies away from city lights.
Ancient debris
The Leonids are bits of debris left behind by repeated passages through the inner solar system of the comet Tempel-Tuttle. Each November, Earth crosses various trails of debris, which have spread out over centuries and millennia. Dense debris trails have caused incredible meteor storms in years, past, notably 1998 through 2002
Since then the show has been back to normal. But recent computer modeling suggests a brief outburst.
"For parts of Europe, Africa and eastern North America, a far more prolific Leonid show could be in the offing this year," said Joe Rao, SPACE.com's Skywatching Columnist.
This year is not expected to be as memorable as some but well worth a look, astronomers say. The Leonids are known for producing bright fireballs, which could occur at any time.
The Leonids are so-named because they appear to emanate from Leo. The meteors can race across the sky in any direction, but trace each one back and it'll point to Leo.
Other opportunities
Unfortunately for viewers on the U.S. West Coast, the peak occurs before Leo rises. Outside of the expected peak, the best time to watch for Leonids is in the pre-dawn hours, when the constellation Leo is high in the sky.
The Leonids are actually underway already, ramping up gradually to the peak. The event continues for several days after the peak. So any morning during this time could offer up a handful of meteors each hour. Other shooting stars from other sources typically grace the sky at low rates, too.
Flurries of enhanced activity can come at any time. Cooke suggests taking a look in the pre-dawn hours Friday, Saturday and Sunday. Up to 10 shooting stars per hour are possible any of these mornings.
Precise prediction of meteor showers is an infant science, so those in position to observe the possible outburst should plan to head out a half-hour before the predicted peak, allowing eyes time to adjust to the dark, and stay out for up to a half hour after the expected peak.
No special equipment is needed. Telescopes and binoculars are of no use.
A lounge chair or blanket and warm clothes are all you need [meteor watching tips]. Find a dark location with a clear view of the Eastern horizon. Lie back, face East, and scan as much of the sky as you can . You never know exactly where a Leonid will appear.
Using a FM Radio or TV to hear, or see Meteors!
How to listen
On the FM band, you stand the best chance of success by monitoring the low-end of the band, below 91.1 MHz. Thats because most low-power stations are found there, generally free of local interference from the higher-power commercial stations that are found farther up the dial.
"I think the FM broadcast band would be best for most people, if they can find a clear frequency, preferably near the low end of the band," says long time amateur radio operator, Shelby Ennis (W8WN) of Kentucky. "A small external antenna would help."
Tune to a blank spot on a specific frequency. From altitudes of 60 to 90 miles, meteors are capable of reflecting signals from stations 1,000 miles or more away.
So exactly what are you trying to hear?
What to listen for
A bright meteor can cause a distant radio station to suddenly come blaring in loud and clear for a fraction of a second (referred to by radio amateurs as a "ping"). Or, depending on how long the trail of ionized gas persists, you may continue to hear the stations signal albeit much weaker for perhaps 10 to 20 seconds or more.
Youll have better success if you turn can off the stereo and "mute" functions on your FM radio. Radios with an indoor antenna are okay, but youll do much better with an antenna that is mounted outdoors.
Another radio amateur who monitors meteor showers on radio, Ilkka Yrjölä at (OH5IY) of Kuusankoski, Finland, notes that "indoor antennas pick up noise from household electronics and FM radio signals may actually be severely attenuated by the walls, though one may receive all the local stations just fine. An outdoor antenna is something to have, or if the conditions are no good, drive a car to a park, or outside the city to a relatively clear spot and listen to FM from there."
Ennis agrees on this final point. "Some have done well just sitting in their car, watching the sky and monitoring the FM band that way."
Tuning in
You can try listening anytime after the Leonid radiant comes above your local horizon (generally after 11 p.m. local time).
For those in New England and the Canadian Maritimes, this is around the time of the first predicted Leonid outburst. As such, it might be worthwhile to try and listen during the two hours or so surrounding this first peak, regardless of the actual geometry of the radiants location.
However, the very best time to listen is when the radiant is roughly halfway up above the horizon as seen from a point halfway between you and the station transmitter. From a given location, the Leonid radiant is at this height at around 3:00 a.m. local time when it is in the east-southeast sky, and again around 9:00 a.m. when its in the west-southwest.
You should try tuning to a station located in a direction perpendicular to the radiant. So, if you are listening when the radiant is up in the east-southeast sky, the better listening directions are to your north-northeast and south-southwest; when the radiant is in the west-southwest sky, try for stations to your north-northwest and south-southeast.
People in the Mountain Time Zone of North America are particularly favored, since the Leonid radiant will be at or very near the proper height above the east-southeast horizon around the time when the second outburst of meteor activity is expected to occur.
Again, you stand the best chance of success if you try tuning your receiver to a blank spot on the FM dial that is at or below 91.1 MHz.
Unfortunately, prospective listeners who live in or near large cities may run into a problem analogous to visual observers trying to find a location free of light pollution, namely, there might not be any blank spots to be found on the FM dial. If you find that this is the case in your area, dont despair.
Try watching for meteors on your TV.
Televised event
Basically, television is nothing more than FM radio with pictures. Of course, in this case we are not talking about a TV set that is hooked up to a local cable outlet or a satellite dish! Were talking about using an old-fashioned TV antenna, either mounted on your roof or at the very least a smaller external antenna (such as "rabbit ears").
Look for a vacant channel between channels 2 and 6. Along with occasionally hearing the audio from a distant station suddenly bursting forth, you may actually see a picture for a few moments, or some lines across the screen as the TV set tries to lock up on a sudden signal, especially if the meteors ionization trail is particularly dense.
One thing you might want to keep in mind if youre listening to your radio while simultaneously watching the sky: Not every meteor that you see visually will result in a ping of reception.
More often than not, youll probably be hearing activity without actually seeing any meteors. The reason is that the majority of the meteors that induce enhanced reception are streaking through the atmosphere many hundreds of miles away, near or beyond your horizon.
On a typical non-Leonid night, listening for meteor activity on radio means perhaps waiting to hear an occasional ping coming through between lengthy intervals perhaps lasting many minutes. But if the Leonids attain predicted rates of a thousand per hour or more, the shower could translate into almost continuously hearing a distant station whose signal will seem to vary dramatically in intensity as it bounces off numerous meteor trails.
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