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How to View Meteor Showers - How to "See More Meteors"


+ What are meteor showers? + What are the "LEONIDS"? + Where can I see showers? + When can I see a shower? + How can I see more meteors? + Why amateur observing? + How can I learn more? + Latest Meteor Showers!

What are meteor showers?

Meteor showers are annual events, during which more shooting stars than usual can be seen over a period of several nights, each meteor appearing to point back to (or "radiate from") a particular point in the sky. These meteor showers actually occur because the earth, in its annual orbit around the sun, passes through a particular band of dust particles called a "meteoroid stream". During the course of a full solar year - when the Earth goes one full revolution around the Sun - we encounter many such meteoroid streams large and small!

Meteoroid streams are in fact the debris trails left behind by periodic comets, or in rare cases (e.g., the Geminids) by asteroids. Meteoroid streams can be visualized (in the words of Stuart Atkinson) as "rivers of crumbling comet dust". However, though streams may derive from a comet, there are forces which constantly act on the particles in meteoroid streams to move them around: thus, the meteor shower's "orbit" need not correspond with a parent comet's orbit! And it is in fact this very motion that makes meteoroid streams and their associated showers so interesting...

                          

Want to read about the LEONIDS?

Before delving into detail on the exciting area of observing regular annual showers, many Websurfers may wish to read more about the much publicized Leonid METEOR STORM...

Here is an entire page devoted to the subject of meteor storms and how to observe them. And in particular, look for our critical list of Web links related to the Leonid meteor storms of 1998 through 2002!

http://www.meteorobs.org/storms.html#leonids

Note that the Leonids are not just an occasional storm, however... They are also a fairly reliable annual meteor shower!

                          

Where can I see meteor showers?

Meteoroid streams are always much wider than the Earth. Because of this, you will see a shower's meteors scattered over your whole sky, not for just one night but for from 3 up to 60 nights each year! Thus you don't need to face any one direction to see a meteor shower well! Nor will a meteor shower only be visible from one area of the earth. Unlike geographically narrow astronomical events like solar eclipses, lunar occultations, or bright fireballs, a meteor shower will often be visible over much of the Earth's surface!

However, not all of Earth will be able to see a given meteor shower. That is because the bulk of our globe shields some areas of Earth's surface from the impact of meteoroid particles - in effect, some area of the world map is always in the Earth's "shadow" with respect to any meteoroid stream. This "shadow" is bounded by the area of Earth in which a certain point on the Celestial Sphere (the "bowl" of the Heavens) is not visible. This special point is unique to each meteor shower, and is characterized as being the point in the sky to which all visible tracks in the heavens of meteors from the shower - no matter where they are seen in the sky, or from what point on Earth - all seem to trace back to. This point is the "radiant" of a shower!

Finally, because there is often fine-grained structure within meteoroid streams, which the earth will "sample" as it passes through them from hour to hour, not all areas of the Earth will necessarily see the exact same show from a meteor shower! For instance, the peak activity for a particular shower may occur while it is daylight in your area of the earth! Or it may be dark during the shower's peak "maximum", but the shower radiant point may be low on your horizon, reducing the number of meteors you see - or again below the horizon, making it impossible to see any meteors from the shower at that particular hour.

                          

When can I see meteor showers?

Among the best known annual meteor showers are the Perseids in August, the Leonids in November, and the Geminids in December. But there are actually showers of varying lesser strengths throughout the year!

The following table is adapted from IMO's Meteor Calendar, 2002. (Mirror site here.)

Shower Activity Peak Relative Shower Rating Period Date Speed *Quadrantids Jan 01-Jan 05 Jan 03 Medium Very Strong Alpha-Centaurids Jan 28-Feb 21 Feb 08 Fast Weak Virginids Jan 25-Apr 15 (Mar 24) Med-Slow Weak *Lyrids Apr 16-Apr 25 Apr 22 Med-Fast Medium to Strong Pi-Puppids Apr 15-Apr 28 Apr 23 Slow Usually Weak *Eta-Aquarids Apr 19-May 28 May 05 Fast Strong to Very Strong Sagittarids Apr 15-Jul 15 (May 19) Med-Slow Weak July Phoenicids Jul 10-Jul 16 Jul 13 Med-Fast Usually Weak - SOUTH ONLY Pisces Austrinids Jul 15-Aug 10 Jul 28 Medium Weak *South Delta-Aquarids Jul 12-Aug 19 Jul 28 Medium Strong *Perseids Jul 17-Aug 24 Aug 12 Fast Very Strong Alpha-Aurigids Aug 25-Sep 05 Sep 01 Fast Medium Delta-Aurigids Sep 05-Oct 10 Sep 08 Fast Weak Draconids Oct 06-Oct 10 Oct 08 Slow Very Weak - Can STORM *Orionids Oct 02-Nov 07 Oct 21 Fast Strong South Taurids Oct 01-Nov 25 Nov 05 Med-Slow Weak North Taurids Oct 01-Nov 25 Nov 12 Med-Slow Weak *Leonids Nov 14-Nov 21 Nov 17 Fast Strong to STORM Alpha-Monocerotids Nov 15-Nov 25 Nov 21 Fast Usually Weak Phoenicids Nov 28-Dec 09 Dec 06 Slow! Usually Weak - SOUTH ONLY Puppid-Velids Dec 01-Dec 15 (Dec 07) Medium Medium - SOUTH ONLY *Geminids Dec 07-Dec 17 Dec 14 Medium Very Strong Coma Berenicids Dec 12-Jan 23 Dec 19 Fast Weak Ursids Dec 17-Dec 26 Dec 22 Medium Medium * - "Major Showers" are marked with a "*". Peaks in parenthesis show showers with diffuse activity profiles. Showers marked "SOUTH ONLY" are not observable from North Temperate latitudes.
                          

How can I see more meteors?

Observing meteors is simple: just lie out on a lawn chair or sleeping bag under the night sky, and look up! However, if you want to have the best chance of seeing meteors - more than a few per hour - there are some things you can do to "improve the meteor show":
Watch from the darkest site you feel safe at:
This means getting away from all man-made lights, and also trying to watch when the moon is not up in the sky (or is a very thin crescent). Man-made light is partly the light which glows in the sky whenever a city, town or mall is nearby - this is "light pollution". But man-made light may also be from smaller sources which are directly in your line of sight, such as "security" lights, poorly designed street lights, your own porch light, etc. - this is called "light trespass". Any man-made light should be avoided, to get a truly dark, meteor-filled sky.
Watch as late in the nighttime as you can, up till dawn:
Because the earth orbits the sun in the same direction as its daily spin, we are on the "trailing" side of the globe before midnight. This means that meteoroids must "catch up" to us in order to burn up in our atmosphere, and will be slower (and so fainter) when they do. After midnight of course, the situation is reversed... The result is that you usually see many more meteors near dawn than near dusk!
Watch when you know a meteor shower radiant is above the horizon:
No meteors can be seen from a shower when it's apparent "radiant" is not in the sky! Active and "peak" dates for major meteor showers are above. The radiants for most of these are up by around midnight, so you're generally safe watching after then. Some showers, like the Perseids, are up all night from some locations, but usually get higher in the sky (and thus show you more meteors) as the night wears on.
[NOTE the periodic "Draconid" shower in October is an exception to this rule: when these meteors appear at all in a given year, they may well appear in early evening!]
Watch from a spot without obstructions, ideally on a clear night:
Obviously, if there is an area of the sky you cannot see, you will miss the meteors that appear in that part of the sky! For the same reason, try facing high enough up in the sky so that no part of the horizon blocks your view. This is usually more fun anyway!
                          

Why should I try amateur observing?

Few amateur astronomers (or even professionals) realize it, but by observing meteor showers, we are really observing the material, dynamics, and evolution of our solar system! By watching meteors, you are collecting first-hand data on the debris of comets, often the most well-preserved "original bodies" in our solar system.

Not only that, but there are many forces in our solar system which only affect particles the size of meteoroids. By collecting data on how these forces affect meteor showers over time, we are in effect looking back at the forces which dominated our solar system when it was nothing else but a cloud of dust and gas circling the new-born Sun... Pretty amazing for "mere" lawn-chair skygazing!

                          

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 Earth) on amateur meteor observing for fun and Science:
http://www.namnmeteors.org/

To learn about watching the (annual) Leonid shower in particular, try Gary Kronk's very readable "Annual Meteor Shower Calendar", under "November" for the Leonids:
http://comets.amsmeteors.org/meteors/showers/leonids.html

North American observers should also peruse the American Meteor Society's fact-filled pages about meteor observing, fireballs, radio meteors and other topics, at:
http://www.amsmeteors.org

Finally for yet more information of a technical nature on Leonid outbursts, including riveting reports of observing efforts in 1998, 1999, 2000, 2001 and 2002, try Dr. Peter Jenniskens' site at NASA:
http://leonid.arc.nasa.gov/

Last but not least, another excellent site giving predictions of a possible Leonid outburst in 2006, is scientists' David Asher and Rob McNaught's pages on the Armaugh Observatory site:
http://www.arm.ac.uk/leonid/dust2006.html


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Information on the Latest Meteor Showers

If you want to learn more about meteor showers which are coming up this month, try browsing the latest issue of the regular "NAMN Notes" newsletter put out by the North American Meteor Network! There you can find in-depth discussions of interesting upcoming meteor showers, news related to the science of meteors, and also upcoming social and academic events which may be of interest to amateurs!
http://www.namnmeteors.org/namnnotes.html

Also highly recommended is the "Weekly Meteor Outlook", written for the American Meteor Society by prolific observer and international meteor notable Bob Lunsford, usually updated weekly on the Web at:
http://www.amsmeteors.org/lunsford/


Clear skies!
Lew Gramer <dedalus@alum.mit.edu>