International Meteor Organization
IMO Meteor Shower Calendar 2002
compiled by Alastair McBeath and Rainer Arlt
based on information in IMO Monograph No.2:
Handbook for Visual Meteor Observers,
edited by Jürgen Rendtel, Rainer Arlt and
Alastair McBeath, IMO, 1995,
additional material extracted from reliable data analyses produced since,
and comments provided by Rainer Arlt.
Layout by André Knöfel.
Prepared for WWW by Sirko Molau
IMO's Meteor Shower Calendar for 2002 contains the following items:
- Introduction
- Highlights January to March
- Highlights April to June
- Highlights July to September
- Highlights October to December
- Large Radiant sizes and meteor plotting
- Optimum radiant diameters for shower association
- Error limits for the angular velocity
- Angular meteor velocities
- Abbreviations
- Tables
- Lunar phases for 2002
- Working list of visual meteor showers
- Radiant positions during the year in alpha and delta
- Working list of daytime radio meteor streams
- Useful addresses
Introduction
Welcome to the 2002 International Meteor Organization (IMO) Meteor Shower Calendar. The year provides a mixture of Moon-free and Moon-affected major showers, with the Orionids and the potentially storm-rate Leonids especially badly moonlit, though the Perseids and alpha-Centaurids enjoy darker skies. It's a good year too for checking up on uncertain and minor sources like the gamma-Normids (March), June Lyrids, Pegasids (July), the Taurids (November) and the host of minor streams in early December, amongst others. Do not forget that monitoring of meteor activity should ideally be carried on throughout the rest of the year too, however! We appreciate that this is not practical for many observers, and this Calendar was devised as a means of helping observers deal with reality by highlighting times when a particular effort may most usefully be employed. Although we include timing predictions for all the more active night-time and daytime shower maxima, based on the best available data, please note that in many cases, such maxima are not known more precisely than to the nearest 1° of solar longitude (even less accurately for the daytime radio showers, which have only recently begun to receive regular attention again). In addition, variations in individual showers from year to year mean past returns are at best only a guide as to when even major shower peaks can be expected, plus as some showers are known to show particle mass-sorting within their meteoroid streams, the radio, telescopic, video, visual and photographic meteor maxima may occur at different times from one another, and not necessarily just in these showers. The majority of data available are for visual shower maxima, so this must be borne in mind when employing other observing techniques.
The heart of the Calendar is the Working List of Visual Meteor Showers, thanks to regular updating from analyses using the IMO's Visual Meteor Database, the single most accurate listing available anywhere today for naked-eye meteor observing. Even this can never be a complete list of all meteor showers, since there are many showers which cannot be properly detected visually, and some which only photographic, radar, telescopic, or video observations can separate from the background sporadic meteors, present throughout the year.
The IMO's aims are to encourage, collect, analyze, and publish combined meteor data obtained from sites all over the globe in order to further our understanding of the meteor activity detectable from the Earth's surface. Results from only a few localized places can never provide such total comprehension, and it is thanks to the efforts of the many IMO observers worldwide since 1988 that we have been able to achieve as much as we have to date. This is not a matter for complacency, however, since it is solely by the continued support of many people across the whole world that our steps towards constructing a better and more complete picture of the near-Earth meteoroid flux can proceed. This means that all meteor workers, wherever they are and whatever methods they use to record meteors, should follow the standard IMO observing guidelines when compiling their information, and submit their data promptly to the appropriate Commission for analysis.
Visual and photographic techniques remain popular for nightly meteor coverage (weather permitting), although both suffer considerably from the presence of moonlight. Telescopic observations are much less popular, but they allow the fine detail of shower radiant structures to be derived, and they permit very low activity showers to be accurately detected. Video methods continue to be dynamically applied as in the last few years, and are starting to bear considerable fruit. These have the advantages, and disadvantages, of both photographic and telescopic observing, but are increasing in importance. Radio receivers can be utilized at all times, regardless of clouds, moonlight, or daylight, and provide the only way in which 24-hour meteor observing can be accomplished for most latitudes. Together, these methods cover virtually the entire range of meteoroid sizes, from the very largest fireball-producing events (using all-sky photographic patrols or visual observations) through to tiny dust grains producing extremely faint telescopic or radio meteors.
However and whenever you are able to observe, we wish you all a most successful year's work and very much look forward to receiving your data. Clear skies!
January to March
Of the major streams active in the first quarter of the year, the northern-hemisphere Quadrantids (maximum due around January 3, 18h UT) lose out to the gibbous Moon, waning from full on 2001 December 30, though the southern-hemisphere alpha-Centaurids in early February are Moon-free. The minor streams too enjoy mixed fortunes. The minor delta-Cancrids are well-placed for observers in mid January, but the very weak delta-Leonids (peaking near February 24) are lost to full Moon, for instance. Also underway from late January to mid April is the diffuse ecliptical stream complex of the Virginids, probably producing several low, and poorly-observed, maxima in March or early April. Mid-March sees a perfectly moonless spell for checking on the gamma-Normids, whose details are most uncertain. Daylight radio shower peaks are theoretically due from the Capricornids/Sagittarids around February 1, 14h UT, and the chi-Capricornids on February 13, 15h UT. Recent radio results suggest the Cap/Sgr maximum may variably fall up to 2 or 3 days later than this however, while activity near the expected chi-Capricornid peak has tended to be slight and perhaps a day or so later in 1999-2000. Both showers have radiants >10°-15° west of the Sun at maximum, so cannot be regarded as visual targets even from the southern hemisphere.
delta-Cancrids
Active : January 1-24; Maximum : January 17 (lambda = 297°); ZHR = 4; Radiant : alpha = 130°, delta = +20°; Radiant drift: see Table 6; V = 28 km/s; r = 3.0; TFC : alpha = 115°, delta = +24° and alpha = 140°, delta = +35° (beta>40° N); alpha = 120°, delta = -03° and alpha = 140°, delta = -03° (beta<40° N). Figure 1: Radiant position of the delta-Cancdrids
This minor stream of predominantly faint meteors is well-suited to telescopic observations, with a large, complex, diffuse radiant that probably consists of several sub-centers. Visual observers should assume a minimum radiant size of roughly 20° in alpha by 10° in delta about the radiant point given above. This type of large, loose radiant area is similar to the Virginids, and the delta-Cancrids are probably an early part of the Virginid activity. Recent observations have suggested the peak may occur close to lambda = 291° (2002 January 11), though ZHRs do not rise above 3-4 even then. New Moon on January 13 means either peak time will be moonless, an excellent opportunity to see what occurs. The long northern winter nights are ideal for making observations, though the radiant is above the horizon almost all night in either hemisphere.
alpha-Centaurids
Active : January 28-February 21; Maximum : February 8, 4:20h UT (lambda = 319.2°); ZHR = variable, usually around 6; Radiant : alpha = 210°, delta = -59°; Radiant drift: see Table 6; V = 56 km/s; r = 2.0. Figure 2: Radiant position and drift of the alpha-Centaurids
The alpha-Centaurids are one of the main southern hemisphere high points in the opening months of the year, producing many very bright, even fireball-class, objects (meteors of at least magnitude -3). Their peak ZHR is normally around 5-10, but in 1974 and again in 1980, bursts of only a few hours' duration yielded activity closer to 20-30. As we have no means of telling when another such event might happen, photographic, video and visual observers are urged to be alert. Thanks to their brilliance, even a normal alpha-Centaurid return is worth looking out for, with almost one-third of shower meteors leaving persistent trains. The radiant is nearly circumpolar for much of the sub-equatorial inhabited Earth, and is at a useful elevation from late evening onwards. This year, the Moon is a waning crescent four days from new at the maximum, rising between roughly 1:00-1:30 local time on February 7-8 for typical southern hemisphere sites, and should not be a particular problem.
gamma-Normids
Active : February 25-March 22; Maximum : March 13, (lambda = 353°); ZHR = 8; Radiant : alpha = 249°, delta= -51°; Radiant drift: see Table 6; V = 56 km/s; r = 2.4; TFC : alpha = 225°, delta = -26° and alpha = 215°, delta = -45° (beta< 15° S). Figure 3: Radiant position and drift of the gamma-Normids
Gamma-Normid meteors are similar to the sporadics in appearance, and for most of their activity period, their ZHR is virtually undetectable above this background rate. The peak itself is normally quite sharp, with ZHRs of 3+ often noted for only a day or two to either side of the maximum. Activity may vary somewhat at times, with occasional broader, or less obvious, maxima having been reported in the past, and in 1999 independent observations in Australia and South Africa suggested the peak may have fallen on March 17. Post-midnight watching yields best results, when the radiant is rising to a reasonable elevation from southern hemisphere sites (the radiant does not rise for many northerly sites). The shower badly needs more regular observation, and new Moon on March 14 makes 2002 an excellent year to make a start. All techniques can be employed.
April to June
Meteor activity picks up towards the April-May boundary, with shower peaks from the badly-moonlit Lyrids (due on April 22, 10:30 UT, but it may extend for several hours around this time based on results from recent years) and the pi-Puppids (expected towards April 23, 21h UT). In early May, the eta-Aquarids are somewhat less Moon-affected. Later in May and throughout June, most of the meteor action switches to the daytime sky, with six shower maxima expected during this time. Although a few meteors from the omikron-Cetids and Arietids have been reported from tropical and southern hemisphere sites visually in past years, ZHRs cannot be sensibly calculated from such observations. For radio observers, the expected UT maxima for these showers are as follows:
April Piscids -- April 20, 14h UT; delta-Piscids -- April 24, 14h UT; epsilon-Arietids -- May 9, 13h UT; May Arietids -- May 16, 14h UT; o-Cetids -- May 20, 13h UT; Arietids -- June 7, 16h UT; zeta-Perseids -- June 9, 16h UT; beta-Taurids -- June 28, 15h UT.
Signs of most of these peaks were found in radio data from 1994-2000, though some are difficult to define because of their proximity to other sources, while the Arietid and zeta-Perseid maxima tend to blend into one another, producing a strong radio signature for several days in early June.
There is the possibility of a return of the Taurid meteoroid "swarm" during June 2002 according to work done by David Asher, which may be detected as an increased radio meteor flux during the zeta-Perseids or the beta-Taurids, both of which are probably associated with the Taurid Complex of meteor showers, asteroids and comets. The most likely time for anything to be detected is about 5-8 days before the beta-Taurid peak, thus around June 20-23, but the enhancement could be quite minor, and its timing is unknown. An investigation into events possibly connected with an earlier predicted Taurid "swarm" encounter in June 1999 was inconclusive, though another "swarm" prediction for the night-time October-November Taurids in 1998 was apparently confirmed by radio and visual data in the last days of October. The Earth will pass similarly close to the center of the theoretical swarm in 2002 June to 1998 October-November.
The visual ecliptical complexes continue with some late Virginids up to mid April, after which come the minor Sagittarids, with their probable peaks in May-June. Checking for any possible June Lyrids should be feasible this year, but the waning gibbous Moon will make June Bootid hunting very difficult around their potential peak on June 27, about 13:30 UT, a time based on 1998 results. If any June Bootid rates do occur, they may last up to half a day centred on this time.
eta-Aquarids
Active : April 19-May 28; Maximum : May 5, 5:30 UT (lambda = 45.5°); ZHR = 60 (occasionally variable); Radiant : alpha = 338°, delta = -01°; Radiant drift: see Table 6; V = 66 km/s; r = 2.7; TFC : alpha = 319°, delta = +10° and alpha = 321°, delta = -23° (beta<20° S). Figure 4: Radiant position and drift of the eta-Aquarids
A relatively broad maximum, sometimes with a variable number of submaxima, usually occurs in early May. ZHRs are generally above 30 between about May 3-10, based on IMO observations during 1988-1997, analyzed by Tim Cooper, and confirmed by visual and radio observations since. The waning crescent Moon on May 6 will rise around 1:00-1:30 local time for southern hemisphere sites, or up to an hour later for low to mid northerly ones, so the shower is reasonably-placed for watchers in 2002, and the moonlight circumstances are still better only a day or two later. All forms of observing can be used to study the eta-Aquarids, with radio work allowing activity to be followed even from many northern latitude sites throughout the daylight morning hours. The radiant culminates at about 8h local time.
June Lyrids
Active : June 11-21;
Maximum : June 16 (lambda = 85°);
ZHR = variable, 0 - 5;
Radiant : alpha = 278°, delta = +35°;
Radiant drift: June 10 alpha = 273°, delta = +35°,
June 15 alpha = 277°, delta = +35°,
June 20 alpha = 281°, delta = +35°;
V = 31 km/s;
r = 3.0;
Figure 5: Radiant position of the June Lyrids
This shower does not feature in the current IMO Working List of Visual Meteor Showers, as apart from some activity seen from northern hemisphere sites in a few years during the 1960s (first seen 1966) and 1970s, evidence for its existence has been virtually zero since. In 1996, several observers independently reported some June Lyrids, though no definite activity was subsequently found in 1997-1999 (in 2000, the full Moon intervened). The probable 2002 weekend maximum benefits from a waxing crescent Moon (setting within 30 minutes of local midnight north of the equator on June 15-16 and 16-17), and we urge all observers who can to cover this possible stream. The radiant is a few degrees south of the bright star Vega (alpha Lyrae), so will be well on-view throughout the short northern summer nights, but there are discrepancies in its position in the literature. All potential June Lyrids should be carefully plotted, paying especial attention to the meteors' apparent velocities. Confirmation or denial of activity from this source by photography or video would be very useful too.
July to September
The minor Pegasid and July Phoenicid showers are both superbly-placed near new Moon in July, while other minor shower activity continues from various near-ecliptic sources throughout the quarter, first from the Sagittarids till mid July, then from the Aquarids and Capricornids, and finally the Piscids into September. The two strongest sources both suffer from the waning gibbous Moon, the Southern delta-Aquarids (maximum on July 28, along with the minor Piscis Austrinids) and the alpha-Capricornids (peak on July 30). The Southern iota-Aquarid and Northern delta-Aquarid maxima are much more favourable, with new Moon on August 8, which also makes this a marvellous year for the Perseids. Something of the minor kappa-Cygnid peak on August 18 may still survive the waxing gibbous Moon by then, though a few should be visible for much of August in darker skies, but the very weak Northern iota-Aquarid maximum falls casualty to bright moonlight on August 20. Last quarter Moon on August 31 will create problems for the alpha-Aurigids (peak on September 1, 6h UT), as it will rise just as the Aurigid radiant is pulling usefully clear of the horizon for northern hemisphere watchers. The delta-Aurigids slightly later in September are much more accessible. For daylight radio observers, the interest of May-June has waned, but there remain the visually-impossible gamma-Leonids (peak circa August 25, 15h UT, though not found in recent radio results), and a tricky visual shower, the Sextantids (maximum expected on September 27, 15h UT, but possibly occurring a day earlier. In 1999 a strong return was detected at lambda about 186°, equivalent to 2002 September 29). The waning Moon presents extra problems for visual observers hoping to catch some Sextantids in late September, though the radiant rises less than an hour before dawn in either hemisphere.
Pegasids
Active : July 7-13; Maximum : July 9 (lambda = 107.5°); ZHR = 3; Radiant : alpha = 340°, delta = +15°; Radiant drift: see Table 6; V = 70 km/s; r = 3.0; TFC : alpha = 320°, delta = +10° and alpha = 332°, delta = +33° (beta>40° N); alpha = 357°, delta = +02° (beta<40° N).
Monitoring this short-lived minor shower is never easy, as a few cloudy nights mean its loss for visual observers. The shower is best-seen in the second half of the night, and with the Moon just one day before new on July 9, conditions are perfect both for observers at the more favourable northern hemisphere sites, and those further south. The maximum ZHR is generally low, and swift, faint meteors can be expected. Telescopic observing would be especially useful.
July Phoenicids
Active : July 10-16; Maximum : July 13 (lambda = 111°); ZHR = variable 3-10; Radiant : alpha = 032° , delta = -48°; Radiant drift: see Table 6; V = 47 km/s; r = 3.0; TFC : alpha = 041°, delta = -39° and alpha = 066°, delta = -62° (beta<10° N). Figure 6: Radiant position of the July Phoenicids
This minor shower can be seen from the southern hemisphere, from where it attains a reasonable elevation above the horizon after midnight. This is an ideal year to watch it, since the waxing crescent Moon will have set long before then. Visual activity can be quite variable, and indeed observations show it to be a richer radio meteor source (possibly also telescopically too, but more results are needed). The peak has not been well-observed for some considerable time, though recent years have brought maximum ZHRs of under 4, when the winter weather has allowed any coverage at all. More data would be very welcome!
Aquarids
Southern iota-Aquarids
Active : July 25-August 15; Maximum : August 4 (lambda = 132°); ZHR = 2; Radiant : alpha = 334°, delta = -15°; Radiant drift: see Table 6; V = 34 km/s; r = 2.9; TFC : alpha = 255° to 0°, delta = 0° to +15°, choose pairs separated by about 30° in alpha (beta<30° N).
Northern delta-Aquarids
Active : July 15-August 25; Maximum : August 8 (lambda = 136°); ZHR = 4; Radiant : alpha = 335° , delta = -05°; Radiant drift: see Table 6; V = 42 km/s; r = 3.4; TFC : alpha = 255° to 0°, alpha = 0° to +15°, choose pairs separated by about 30° in alpha (beta<30° N). Figure 7: Radiant position and drift of Aquarid radiant complex
The July-August Aquarid showers are all rich in faint meteors, making them well-suited to telescopic work, although enough brighter members exist, especially in the delta-Aquarids, to make visual and photographic observations worth the effort too, primarily from more southerly sites. Such a concentration of radiants in a small area of sky means that familiarity with where they are is essential for accurate shower association for all observing nights. Visual watchers in particular should plot every potential stream member seen in this region of sky rather than trying to make shower associations in the field.
In 2002, only the Southern iota-Aquarid and Northern delta-Aquarid maxima from this stream complex benefit from early August's waning to new Moon. Moonrise on August 4 (the Southern iota-Aquarid maximum) favours observations from southern hemisphere sites particularly, as it occurs around 2:30-3:00 local time there, compared to near local midnight to 1h at mid-northern latitudes. The probable Northern delta-Aquarid peak on August 8 is perfectly-placed for new Moon. Neither shower has been closely studied in recent years, and any reliable data would be very useful. The Aquarid/Capricornid radiants are above the horizon for much of the night.
Perseids
Active : July 17-August 24;
Maxima : August 12, 20:15 UT (lambda = 139.91°), possible feature,
August 12, 22:30 UT (lambda = 140.0°) and
August 13, 08:30 UT (lambda = 140.4°), possible feature;
ZHR = variable 100-110 (main peak);
Radiant : alpha = 046°, delta = +58°;
Radiant drift: see Table 6;
V = 59 km/s;
r = 2.6;
TFC : alpha = 019°, delta = +38° and
alpha = 348°, delta = +74° before 2h local time;
alpha = 043°, delta = +38° and
alpha = 073°, delta = +66° after 2h local time (beta>20° N);
PFC : alpha = 300°, delta = +40°,
alpha = 000°, delta = +20° or
alpha = 240°, delta = +70° (beta>20° N).
Figure 8: Radiant position of the Perseids
The Perseids were one of the most exciting and dynamic meteor showers during the last decade, with outbursts at the shower's primary maximum producing EZHRs of 400+ in 1991 and 1992. Rates from this peak decreased to about 100-120 by the late 1990s, and in 2000 it failed to appear. This was not unexpected, as the outbursts and the primary maximum (which was not noticed before 1988), were associated with the perihelion passage of the Perseids' parent comet 109P/Swift-Tuttle in 1992. The comet's orbital period is about 130 years, so it is now receding back into the outer Solar System, and theory predicts that such outburst rates should dwindle as the comet to Earth distance increases. However, we have still listed this time here, allowing for the annual shift of aboubt +0.05° in lambda the peak had shown from 1991-1999, because confirming the peak's absence at present is as important as observing it again. The most probable maximum time is that of the "traditional" peak, always previously found, close to lambda=140.0°. A new feature first reported from IMO data in 1997 was a tertiary peak at lambda=140.4°, which recurred in 1998 and 1999. ZHRs from this peak have been around 75+/-10 so far, but there are no guarantees it will reappear in 2002. August's new Moon provides a superb opportunity for observers to cover the whole period right across the maximum dates this year whatever happens. As the radiant rises throughout the night for the northern hemisphere, watching from an hour or two before local midnight until dawn twilight grows too strong is eminently practical. If the maxima appear as predicted, the ideal places to be should include Asia and central Russia; Europe and North Africa to the Near East; and North America, respectively.
Visual and photographic observers should need little encouragement to cover this stream, but telescopic and video watching near the main peak would be valuable in confirming or clarifying the possibly multiple nature of the Perseid radiant, something not detectable visually. Recent video results have shown a very simple, single radiant structure however. Radio data would naturally enable early confirmation, or detection, of perhaps otherwise unobserved maxima if the timings or weather conditions prove unsuitable for land-based sites. The only negative aspect to the shower is the impossibility of covering it from the bulk of the southern hemisphere.
delta-Aurigids
Active : September 5 - October 10; Maximum : September 8 (lambda = 166°); ZHR = 6; Radiant : alpha = 060° , delta = +47°; Radiant drift: see Table 6; V = 64 km/s; r = 3.0. TFC : alpha = 052°, delta = +60°, alpha = 043°, delta = +39° and alpha = 023°, delta = +41° (beta>10° S). Figure 9: Radiant position and drift of the alpha- and delta-Aurigids
The delta-Aurigids are an essentially northern hemisphere shower, badly in need of more observations. They are part of a series of poorly-observed radiants in Aries, Perseus, Cassiopeia and Auriga, active from late August to October. British and Italian observers independently reported a possible new radiant in Aries during late August 1997 for example. The delta-Aurigids typically produce low rates of generally faint meteors, and have yet to be well-seen in more than an occasional year. Their radiant reaches a useful elevation after 23h-0h local time, and lunar circumstances are perfect for the likely peak in 2002, with new Moon on September 7. Telescopic data to examine all the radiants in this region of sky - and possibly observe the telescopic beta-Cassiopeids simultaneously - would be especially valuable, but photographs, video records and visual plotting would be welcomed too.
October to December
Early October's new Moon provides near-perfect conditions to watch for any potential Draconid activity this year. Unfortunately, later in the month, both the epsilon-Geminid and Orionid maxima will be lost to full Moon on October 18 and 21 (around 15h UT) respectively, but the minor, extended Taurid peak in early to mid November is largely free from moonlight. Another Leonid storm may occur later in November, and will suffer severe moonlight interference if so. There is a similarly very poor chance to see any repeat of the 1995 alpha-Monocerotid maximum near 20:30 UT on 2002 November 21, because of full Moon. Running into December, for once the new to waxing crescent Moon means all the, mostly minor, shower peaks between December 2-11 can be observed in dark skies, and even the Geminids should still partly survive the waxing gibbous Moon. The minor Coma Berenicid peak on December 20 and the Ursids (visual maximum at lambda=270.7° = December 22, 18:30 UT, 1996 and 2000 radio maximum at lambda about 270.8° = December 22, 21h UT, and 2000 video maximum at lambda=270.78° = December 22, 20:30 UT) are lost to December's full Moon sadly.
Draconids
Active : October 6-10;
Maximum : October 8, 21h 30m UT, (lambda = 195.4°, but see below);
ZHR = periodic, up to storm levels;
Radiant : alpha = 262°, delta = +54°;
Radiant drift: negligible;
V = 20 km/s;
r = 2.6;
TFC : alpha = 290°, delta = +65° and
alpha = 288°, delta = +39° (beta>30° N).
Figure 10: Radiant position of the Draconids
The Draconids are primarily a periodic shower which produced spectacular, brief, meteor storms twice last century, in 1933 and 1946, and lower rates in several other years (ZHRs about 20-500+), most recently in 1998 when the ZHR reached about 700 briefly over the Far East. Almost all the detected showers were seen in years when the stream's parent comet, 21P/Giacobini-Zinner, returned to perihelion, as last in 1998 November. The next return of the comet is in mid 2005. The 1998 outburst happened at lambda=195.075°, equivalent to 2002 October 8, 13:40 UT, although the time used above, closer to lambda=195.4° may be more generally applicable, based on the Earth's closest approach to the node of the comet's orbit. However, in 1999 a wholly unexpected minor outburst was witnessed from the Far East between lambda=195.63-195.76° producing ZHRs about 10-20. This could imply a peak might be seen as late as 2002 October 9, 3:15-6:30 UT, using the 1999-equivalent timing. In 2000, very few visual checks for Draconid activity were made because of bright moonlight, but radio results showed no unusual Draconid signature. The minor 1999 event had been picked up by radio observers. The radiant is circumpolar from many northern hemisphere locations, but is higher in the pre-midnight and near-dawn hours on October 8-10. The nearly-new Moon makes this an almost ideal year to see what the shower yields - even if this is nothing detectable. The possible shower maximum times favour Asia east to western North America (13:50 UT), Europe and North Africa east to most of Asia (21:30 UT), and North America east to the Near East (the October 9 timings). Note that Draconid meteors are exceptionally slow-moving, a characteristic which helps separate genuine shower meteors from sporadics accidentally lining up with the radiant.
Taurids
Southern Taurids
Active : October 1-November 25; Maximum : November 5 (lambda = 223°); ZHR = 5; Radiant : alpha = 052°, delta = +13°; Radiant drift: see Table 6; V = 27 km/s; r = 2.3; TFC : Choose fields on the ecliptic and about 10° E or W of the radiants (beta>40° S).
Northern Taurids
Active : October 1-November 25; Maximum : November 12 (lambda = 230°); ZHR = 5; Radiant : alpha = 058°, delta = +22°; Radiant drift: see Table 6; V = 29 km/s; r = 2.3; TFC : as Southern Taurids. Figure 11: Radiant position of the Northern and Southern Taurids
These two streams form part of the complex associated with Comet 2P/Encke. Defining their radiants is best achieved by careful visual or telescopic plotting, photography or video work, since they are large and diffuse. They are currently being studied using IMO data by Mihaela Triglav. The brightness and relative slowness of many shower meteors makes them ideal targets for photography, while these factors coupled with low, steady, combined Taurid rates makes them excellent targets for newcomers to practice their plotting techniques on. The activity of both streams produces an apparently plateau-like maximum for about ten days in early November, and the shower has a reputation for producing some excellently bright fireballs at times, although seemingly not in every year. David Asher has indicated that increased Taurid fireball rates may result from a "swarm" of larger particles within the Taurid stream complex, and he suggested such "swarm" returns might happen in 1995 and 1998 most recently. In 1995, an impressive crop of bright Taurids occurred between late October to mid November, while in 1998, Taurid ZHRs reached levels comparable to the usual maximum rates in late October, together with an increased flux of brighter Taurids generally. The next potential October-November "swarm" return is not predicted until 2005, but we cannot be sure how correct this is as yet. Some coverage of this interesting late October spell should be possible in 2002, particularly after last quarter Moon on October 29, although it is the early to mid November maximum period which is especially favoured by November's new Moon.
The near-ecliptic radiants for both shower branches mean all meteoricists can observe the streams. Northern hemisphere observers are somewhat better-placed, as here suitable radiant zenith distances persist for much of the late autumnal nights. Even in the southern hemisphere, a good 3-5 hours' watching around local midnight is possible with Taurus well above the horizon, however.
Leonids
Active : November 14-21; Maximum : November 17, 20h UT (lambda = 235.27°, nodal passage), but see text and the Leonid pages ZHR = storm (about 360? in 1998, about 3700 in 1999, about 480 in 2000, may reach storm level again in 2002); Radiant : alpha = 153°, delta = +22°; Radiant drift: see Table 6; V = 71 km/s; r = 2.9; TFC : alpha = 140°, delta = +35° and alpha = 129°, delta = +6° (beta>35° N); or alpha = 156°, delta = -3° and alpha = 129°, delta = +6° (beta<35° N); PFC : before 00h local time alpha = 120°, delta = +40° (beta>40° N); before 04h local time alpha = 120°, delta = +20° (beta>0° N); and after 04h local time alpha = 160°, delta = 0° (beta>0° N); before 04h local time alpha = 120°, delta = +10° (beta<0° N) and after 04h local time alpha = 160°, delta = -10° (beta<0° N). Figure 12: Radiant position and drift of the Leonids
The Leonids' parent comet, 55P/Tempel-Tuttle, reached perihelion last in 1998 February, and a storm was well-seen from the shower in 1999 from the Near East west to the Canary Isles, with strong rates flanking this in 1998 and 2000. Recent stream evolution studies suggest the strongest storm-level Leonid activity associated with this perihelion passage of Tempel-Tuttle may occur this year however. There are no guarantees of course, but even observing an absence of unusual Leonid activity would be valuable information, though not very interesting to witness! The peak time given above is based on the Earth's closest approach to the comet's node. The 1999 storm peaked 50 minutes later than the nodal crossing then, and in 2000 this equivalent time was less than 15 minutes earlier than one of the three stronger maxima that year. The other two maxima peaked within 20-40 minutes of the times predicted by Rob McNaught and David Asher. This year, McNaught and Asher predict only a single maximum, on November 19 at 10:36 UT, when the Earth passes closest to the 1866 Leonid dust trail, and they suggest ZHRs of up to about 25,000 may be seen. Peter Brown, whose Leonid stream modelling was also partly supported by events in 2000, suggests a single, probably non-storm, maximum at 3:50 UT on November 19. These timings may be subject to revision after the 2001 Leonid return, and the IMO's journal WGN will have updates after that occurs.
The radiant rises usefully only around local midnight (or indeed afterwards south of the equator), so the waxing gibbous Moon will cause severe problems almost all night for observing either of the probable peak times noted here. The November 17 timing favours places from Asia and Russia eastwards to the Far East and Australia, while the November 19 maximum predictions are best-suited for European/North African east to eastern Brazilian longitudes (about 4h UT) and North American (about 10:30 UT) longitudes respectively. Despite the bright moonlight, because of the possible strong storm strength, observing is essential. An event of the order McNaught and Asher estimate would still be exceptionally obvious in moonlit skies. Other unexpected peaks are not excluded, so all observers should be alert right over the probable maximum dates, from November 16-20 especially. Remember that various submaxima have been seen at unpredicted times during several recent Leonid returns, and that ZHRs were maintained at 50-100+ for more than a day around the maxima in 1999 and 2000, thus even non-storm activity like this is worth seeing. All observing methods should be utilized, especially photography and video if another storm manifests, and for visual observers particularly, choose a field of view where the Moon will not be in your line of sight. This should not be too difficult, with the Moon passing from eastern Pisces around November 16 to the Taurus-Gemini border by November 20.
chi-Orionids
Active : November 26-December 15; Maximum : December 2, (lambda = 250), ZHR = 3; Radiant : alpha = 082°, delta = +23°; Radiant drift: see Table 6; V = 28 km/s; r = 3.0; TFC : alpha = 083°, delta = +09° and alpha = 080°, delta = +24° (beta>30° S). Figure 13: Radiant position and drift of the chi-Orionids
A weak visual stream, but one moderately active telescopically. Some brighter meteors have been photographed from it too. The shower has at least a double radiant, but the southern branch has been rarely detected. The chi-Orionids may be a continuation of the ecliptic complex after the Taurids cease to be active in late November. The radiant used here is a combined one, suitable for visual work, although telescopic or video observations should be better-able to determine the exact radiant structure. December's new Moon is extremely favourable for covering the shower's best this year, and the radiant is well on display in both hemisphere throughout the night.
Phoenicids
Active : November 28-December 9; Maximum : December 6, 14:20 UT (lambda = 254.25°); ZHR = variable, usually 3 or less, may reach 100; Radiant : alpha = 018°, delta = -53°; Radiant drift: see Table 6; V = 18 km/s; r = 2.8; TFC : alpha = 040°, delta = -39° and alpha = 065°, delta = -62° (beta<10° N). Figure 14: Radiant position of the Phoenicids
Only one impressive Phoenicid return has so far been reported, that of its discovery in 1956, when the ZHR was about 100. Three other potential bursts of lower activity have been reported, but never by more than one observer, under uncertain circumstances. Reliable IMO data shows recent activity to be virtually nonexistent. This may be a periodic shower however, and more observations of it are needed by all methods. Radio workers may find difficulties, as radar echoes from the 1956 event were only 30 per hour, perhaps because these low-velocity meteors produce too little radio-reflecting ionization. Observing conditions this year are almost perfect for all southern hemisphere watchers, with a two-day old Moon setting soon after dark on December 6, while the radiant culminates at dusk, remaining well on view for most of the night.
Puppid-Velids
Active : December 1-December 15; Maximum : December 7 (lambda = 255°); ZHR = about 10; Radiant : alpha = 123°, delta = -45°; Radiant drift: see Table 6; V = 40 km/s; r = 2.9; TFC : alpha = 090° to 150°, delta = -20° to -60°; choose pairs of fields separated by about 30° in a, moving eastwards as the shower progresses (beta<10° N).
This is a very complex system of poorly-studied showers, visible chiefly to those south of the equator. Up to ten sub-streams have been identified, with radiants so tightly clustered, visual observing cannot readily separate them. Photographic, video or telescopic work would thus be sensible, or very careful visual plotting. The activity is so badly-known, we can only be reasonably sure that the highest rates occur in early to mid December, falling with a waxing crescent Moon this year. Some of these showers may visible from late October to late January. Most Puppid-Velid meteors are quite faint, but occasional bright fireballs, notably around the suggested maximum here, have been reported previously. The radiant area is on-view all night, but is highest towards dawn.
Monocerotids
Active : November 27-December 17; Maximum : December 9 (lambda = 257°); ZHR = 3; Radiant : alpha = 100°, delta = +8°; Radiant drift: see Table 6; V = 42 km/s; r = 3.0; TFC : alpha = 088°, delta = +20° and alpha = 135°, delta = +48° (beta>40° N); or alpha = 120°, delta = -03° and alpha = 84°, delta = +10° (beta<40° N);
Only low visual rates are likely from this minor source, making accurate
visual plotting, telescopic or video work essential, particularly because
the meteors are normally faint. The shower's details, even including its
radiant position, are rather uncertain. Recent IMO data show only
weak signs of a maximum as indicated above. Telescopic results suggest a
later maximum, around December 16 (lambda about 264°) from a radiant
at alpha=117°, delta=+20°. This is a good year for making
observations, as the waxing crescent Moon sets by 20h-21h local time
for mid-northern latitudes (later further south), or up to 1.5-2 hours
later for most southern hemisphere sites on December 8-9, while the
radiant is on-show nearly all night, culminating about 1:30 local time.
sigma-Hydrids
Active : December 03-15; Maximum : December 12 (lambda=260°); ZHR = 2; Radiant : alpha=127°, delta=+02°; Radiant drift: see Table 6; V = 58 km/s; r = 3.0; TFC : alpha=095°, delta=00° and alpha=160°, delta=00° (all sites, after midnight only). Figure 15: Radiant position of the sigma-Hydrids
Although first detected in the 1960s by photography, sigma-Hydrids are typically swift and faint, and rates are generally very low, close to the visual detection threshold. Since their radiant, a little over 10° east of the star Procyon (alpha Canis Minoris), is near the equator, all observers can cover this shower. The radiant rises in the late evening hours, but is best viewed after local midnight, so the first quarter Moon will be little problem, setting about 40 minutes before or after local midnight for both northern and southern hemispheres on December 11-12. Recent data indicates the peak may occur up to six days earlier than suggested above, which would be still more favourable for Moon-free watching. The shower would benefit from visual plotting, telescopic or video work to pin it down more accurately.
Geminids
Active : December 7-17; Maximum : December 14, 10h UT (lambda = 262.2°); ZHR = 120; Radiant : alpha = 112°, delta = +33°; Radiant drift: see Table 6; V = 35 km/s; r = 2.6; TFC : alpha = 87°, delta = +20° and alpha = 135°, delta = +49°; before 23h local time, alpha = 87°, delta = +20° and alpha = 129°, delta = +20° after 23h local time (beta>40° N); alpha = 120°, delta = -3° and alpha = 84°, delta = +10° (beta<20° N); PFC : alpha = 150°, delta = +20° and alpha = 60°, delta = +40° (beta>20° N); and alpha = 135°, delta = -5° and alpha = 80°, delta = 0° (beta<20° N) Figure 16: Radiant position of the Geminids and Monocerotids
One of the finest annual showers presently observable. This year, the waxing gibbous Moon will set between 1:30-2:00 local time on December 13-14 (earlier for sites further south), while the Geminid radiant culminates around 2h, so the later stages of the night enjoy moonless skies for all observers. Well north of the equator, the Geminid radiant rises around sunset, and is at a usable elevation from the local evening hours onwards. In the southern hemisphere, the radiant appears only around local midnight or so. Even here, this is a splendid stream of often bright, medium-speed meteors, a rewarding sight for all watchers. The peak has shown slight signs of variability in its maximum rates and peak timing in recent years. The six most reliably observed maxima over the past thirteen years have all occurred between lambda=262.1-262.3° (ZHRs 110-130), which timing extremes equate with 2002 December 14, 7:45 to 12:30 UT. The peak time of 10h UT above is the more probable, and will especially favour sites across all of North America if correct. Some mass-sorting within the stream means the fainter telescopic meteors should be most abundant almost 1° of solar longitude (about one day) ahead of the visual maximum, with telescopic results indicating these meteors radiate from an elongated region, perhaps with three sub-centers. Further results on this topic would be useful, but all methods can be employed to observe the shower.
Large Radiant sizes and meteor plotting
If you are not observing during a major-shower maximum, it is essential to associate meteors with their radiants correctly, since the total number of meteors will be small for each source. Meteor plotting allows shower association by more objective criteria after your observation than the simple imaginary back-prolongation of paths under the sky. With meteors plotted on gnomonic maps, you can trace them back to their radiants by extending their straight line paths. If a radiant lies on another chart, you should find common stars on an adjacent chart to extend this back-prolongation correctly.
How large a radiant should be assumed for shower association? The real physical radiant size is very small, but visual plotting errors cause many true shower meteors to miss this real radiant area. Thus we have to assume a larger effective radiant to allow for these errors. Unfortunately, as we enlarge the radiant, so more and more sporadic meteors will appear to line up accidentally with this region. Hence we have to apply an optimum radiant diameter to compensate for the plotting errors loss, but which will not then be swamped by sporadic meteor pollution. Table 1 gives this optimum diameter as a function of the distance of the meteor from the radiant.
Table 1: Optimum radiant diameters to be assumed for shower association of minor-shower meteors as a function of the radiant distance D of the meteor.
D optimum
diameter
15° 14°
30° 17°
50° 20°
70° 23°
The path-direction is not the only criterion for shower association. The angular velocity of the meteor should match the expected speed of the given shower meteors according to their geocentric velocities. Angular velocity estimates should be made in degrees per second (°/s). To do this, make the meteors you see move for one second in your imagination at the speed you saw them. The path length of this imaginary meteor is the angular velocity in °/s. Note that typical speeds are in the range 3°/s to 25°/s. Typical errors for such estimates are given in Table 2.
Table 2: Error limits for the angular velocity.angular velocity °/s 5 10 15 20 30 permitted error °/s 3 5 6 7 8
In you found a meteor which hits the radiant within the above diameter, check its angular velocity. Table Table 3 gives the angular speeds for a few geocentric velocities, which can be looked up in Table 5 for each shower.
Table 3: Angular velocities as a function of the radiant distance of the meteor and the elevation of the meteor for three different geocentric velocities. All velocities are in °/s. The tables are symmetric in D and h.
V=25 km/s V=40km/s V=60km/s
D 10° 20° 40° 60° 90° 10° 20° 40° 60° 90° 10° 20° 40° 60° 90°
10° 0.4 0.9 1.6 2.2 2.5 0.7 1.4 2.6 3.5 4.0 0.9 1.8 3.7 4.6 5.3
20° 0.9 1.7 3.2 4.3 4.9 1.4 2.7 5.0 6.8 7.9 1.8 3.5 6.7 9.0 10.0
40° 1.6 3.2 5.9 8.0 9.3 2.6 5.0 9.5 13.0 15.0 3.7 6.7 13.0 17.0 20.0
60° 2.2 4.3 8.0 11.0 13.0 3.5 6.8 13.0 17.0 20.0 4.6 9.0 17.0 23.0 26.0
90° 2.5 4.9 9.3 13.0 14.0 4.0 7.9 15.0 20.0 23.0 5.3 10.0 20.0 26.0 30.0
Abbreviations
alpha, delta: Coordinates for a shower's radiant position, usually at maximum; alpha is right ascension, delta is declination. Radiants drift across the sky each day due to the Earth's own orbital motion around the Sun, and this must be allowed for using the details in Table 6 for nights away from the listed shower maxima.
r: Population index, a term computed from each shower's meteor magnitude distribution. r = 2.0-2.5 is brighter than average, while r above 3.0 is fainter than average.
lambda: Solar longitude, a precise measure of the Earth's position on its orbit which is not dependent on the vagaries of the calendar. All lambda are given for the equinox J2000.0.
V: Atmospheric or apparent meteoric velocity given in km/s. Velocities range from about 11 km/s (very slow) to 72 km/s (very fast). 40 km/s is roughly medium speed.
ZHR: Zenithal Hourly Rate, a calculated maximum number of meteors an ideal observer would see in perfectly clear skies with the shower radiant overhead. This figure is given in terms of meteors per hour. Where meteor activity persisted at a high level for less than an hour, or where observing circumstances were very poor, an estimated ZHR (EZHR) is used, which is less accurate than the normal ZHR.
TFC and PFC: suggested telescopic and photographic field centers respectively. beta is the observer's latitude ("<" means "south of" and ">" means "north of"). Pairs of telescopic fields must be observed, alternating about every half hour, so that the positions of radiants can be defined. The exact choice of TFC or PFC depends on the observer's location and the for video camera fields as well.
Tables
Table 4: Lunar phases for 2002.
New First Full Last
Moon Quarter Moon Quarter
January 6
January 13 January 21 January 28 February 4
February 12 February 20 February 27 March 6
March 14 March 22 March 28 April 4
April 12 April 20 April 27 May 4
May 12 May 19 May 26 June 3
June 10 June 18 June 24 July 2
July 10 July 17 July 24 August 1
August 8 August 15 August 22 August 31
September 7 September 13 September 21 September 29
October 6 October 13 October 21 October 29
November 4 November 11 November 20 November 27
December 4 December 11 December 19 December 27
Table 5: Working list of visual meteor showers. Details in this Table
correct according to the best information available in June 2001. Contact
the IMO's Visual Commission for more information. Maximum dates in
parentheses indicate reference dates for the radiant, not true maxima. Some
showers have ZHRs that vary from year to year. The most recent reliable
figure is given here, except for possibly periodic showers that are noted
as "var." = variable. An asterisk (*) in the lambda column indicates the shower may have other or additional peak
times, noted in the text.
Shower Activity Maximum Radiant V r ZHR IMO
Period Date lambda alpha delta Code
° ° ° km/s
Quadrantids Jan 01-Jan 05 Jan 03 283.16 230 +49 41 2.1 120 QUA
delta-Cancrids Jan 01-Jan 24 Jan 17 297 130 +20 28 3.0 4 DCA
alpha-Centaurids Jan 28-Feb 21 Feb 08 319.2 210 -59 56 2.0 6 ACE
delta-Leonids Feb 15-Mar 10 Feb 24 336 168 +16 23 3.0 2 DLE
gamma-Normids Feb 25-Mar 22 Mar 13 353 249 -51 56 2.4 8 GNO
Virginids Jan 25-Apr 15 (Mar 24)(004) 195 -04 30 3.0 5 VIR
Lyrids Apr 16-Apr 25 Apr 22 032.1 271 +34 49 2.9 15 LYR
pi-Puppids Apr 15-Apr 28 Apr 23 033.5 110 -45 18 2.0 var. PPU
eta-Aquarids Apr 19-May 28 May 06 045.5* 338 -01 66 2.7 60 ETA}
Sagittarids Apr 15-Jul 15 (May 20)(059) 247 -22 30 2.5 5 SAG
June Bootids Jun 26-Jul 02 Jun 27 095.7 224 +48 18 2.2 var. JBO
Pegasids Jul 07-Jul 13 Jul 09 107.5 340 +15 70 3.0 3 JPE
July Phoenicids Jul 10-Jul 16 Jul 13 111 032 -48 47 3.0 var. PHE
Pisces Austrinids Jul 15-Aug 10 Jul 27 125 341 -30 35 3.2 5 PAU
Southern delta-Aquarids Jul 12-Aug 19 Jul 28 125 339 -16 41 3.2 20 SDA
alpha-Capricornids Jul 03-Aug 15 Jul 29 127 307 -10 25 2.5 4 CAP
Southern iota-Aquarids Jul 25-Aug 15 Aug 04 132 334 -15 34 2.9 2 SIA
Northern delta-Aquarids Jul 15-Aug 25 Aug 08 136 335 -05 42 3.4 4 NDA
Perseids Jul 17-Aug 24 Aug 12 140.0 046 +58 59 2.6 110 PER
kappa-Cygnids Aug 03-Aug 25 Aug 17 145 286 +59 25 3.0 3 KCG
Northern iota-Aquarids Aug 11-Aug 31 Aug 20 147 327 -06 31 3.2 3 NIA
alpha-Aurigids Aug 25-Sep 05 Aug 31 158.6 084 +42 66 2.5 10 AUR
delta-Aurigids Sep 05-Oct 10 Sep 08 166 060 +47 64 3.0 6 DAU
Piscids Sep 01-Sep 30 Sep 20 177 005 -01 26 3.0 3 SPI
Draconids Oct 06-Oct 10 Oct 08 195.4 262 +54 20 2.6 var. GIA
epsilon-Geminids Oct 14-Oct 27 Oct 18 205 102 +27 70 3.0 2 EGE
Orionids Oct 02-Nov 07 Oct 21 208 095 +16 66 2.9 20 ORI
Southern Taurids Oct 01-Nov 25 Nov 05 223 052 +13 27 2.3 5 STA
Northern Taurids Oct 01-Nov 25 Nov 12 230 058 +22 29 2.3 5 NTA
Leonids Nov 14-Nov 21 Nov 17 235.27 153 +22 71 2.5 storm? LEO
alpha-Monocerotids Nov 15-Nov 25 Nov 21 239.32 117 +01 65 2.4 var. AMO
chi-Orionids Nov 26-Dec 15 Dec 01 250 082 +23 28 3.0 3 XOR
Phoenicids Nov 28-Dec 09 Dec 06 254.25 018 -53 18 2.8 var. PHO
Puppid-Velids Dec 01-Dec 15 (Dec 06)(255) 123 -45 40 2.9 10 PUP
Monocerotids Nov 27-Dec 17 Dec 08 257 100 +08 42 3.0 3 MON
sigma-Hydrids Dec 03-Dec 15 Dec 12 260 127 +02 58 3.0 2 HYD
Geminids Dec 07-Dec 17 Dec 13 262.0 112 +33 35 2.6 120 GEM
Coma Berenicids Dec 12-Jan 23 Dec 20 268 175 +25 65 3.0 5 COM
Ursids Dec 17-Dec 26 Dec 22 270.7 217 +76 33 3.0 10 URS
Table 6: Radiant positions during the year in alpha and delta.
COM DCA QUA
Jan 0 186 +20 112 +22 228 +50
Jan 5 190 +18 116 +22 231 +49
Jan 10 194 +17 121 +21
Jan 20 202 +13 130 +19 ACE VIR
Jan 30 200 -57 157 +16 DLE
Feb 10 214 -60 165 +10 155 +20 GNO
Feb 20 225 -63 172 +6 164 +18 225 -53
Feb 28 178 +3 171 +15 234 -52
Mar 10 186 0 180 +12 245 -51
Mar 20 192 -3 256 -50
Mar 30 198 -5
Apr 10 SAG LYR PPU 203 -7
Apr 15 224 -17 263 +34 106 -44 ETA 205 -8
Apr 20 227 -18 269 +34 109 -45 323 -7
Apr 25 230 -19 274 +34 111 -45 328 -5
Apr 30 233 -19 332 -4
May 5 236 -20 337 -2
May 10 240 -21 341 0
May 20 247 -22 350 +5
May 30 256 -23
Jun 10 265 -23
Jun 15 270 -23
Jun 20 275 -23 JBO
Jun 25 280 -23 223 +48
Jun 30 284 -23 225 +47 CAP JPE
Jul 5 289 -22 285 -16 SDA 338 +14
Jul 10 293 -22 PHE 289 -15 325 -19 NDA 341 +15 PER PAU
Jul 15 298 -21 032 -48 294 -14 329 -19 316 -10 012 +51 330 -34
Jul 20 299 -12 333 -18 319 -9 SIA 018 +52 334 -33
Jul 25 303 -11 337 -17 323 -9 322 -17 023 +54 338 -31
Jul 30 KCG 308 -10 340 -16 327 -8 328 -16 029 +55 343 -29
Aug 5 283 +58 NIA 313 -8 345 -14 332 -6 334 -15 037 +57 348 -27
Aug 10 284 +58 317 -7 318 -6 349 -13 335 -5 339 -14 043 +58 352 -26
Aug 15 285 +59 322 -7 352 -12 339 -4 345 -13 050 +59
Aug 20 286 +59 327 -6 AUR 356 -11 343 -3 057 +59
Aug 25 288 +60 332 -5 076 +42 347 -2 065 +60
Aug 30 289 +60 337 -5 082 +42 DAU
Sep 5 088 +42 055 +46 SPI
Sep 10 060 +47 357 -5
Sep 15 066 +48 001 -3
Sep 20 071 +48 005 -1
Sep 25 NTA STA 077 +49 009 0
Sep 30 021 +11 023 +5 ORI 083 +49 013 +2
Oct 5 025 +12 027 +7 085 +14 089 +49 GIA
Oct 10 029 +14 031 +8 088 +15 095 +49 EGE 262 +54
Oct 15 034 +16 035 +9 091 +15 099 +27
Oct 20 038 +17 039 +11 094 +16 104 +27
Oct 25 043 +18 043 +12 098 +16 109 +27
Oct 30 047 +20 047 +13 101 +16
Nov 5 053 +21 052 +14 105 +17
Nov 10 058 +22 056 +15 LEO AMO
Nov 15 062 +23 060 +16 150 +23 112 +2
Nov 20 067 +24 064 +16 XOR 153 +21 116 +1
Nov 25 072 +24 069 +17 075 +23 120 0 MON PUP PHO
Nov 30 080 +23 HYD 091 +8 120 -45 014 -52
Dec 5 COM GEM 085 +23 122 +3 096 +8 122 -45 018 -53
Dec 10 169 +27 108 +33 090 +23 126 +2 100 +8 125 -45 022 -53
Dec 15 173 +26 113 +33 094 +23 130 +1 URS 104 +8 128 -45
Dec 20 177 +24 118 +32 217 +75
Table 7: Working list of daytime radio meteor streams. The "Best Observed"
columns give the approximate local mean times between which a four-element
antenna at an elevation of 45° receiving a signal from a 30-kW transmitter
1000 km away should record at least 85% of any suitably positioned radio-
reflecting meteor trails for the appropriate latitudes. Note that this is
often heavily dependent on the compass direction in which the antenna is
pointing, however, and applies only to dates near the shower's maximum.
Shower Activity Max lambda Radiant Best Observed Rate
Date 2000.0 al. de. 50°N 35°S
° ° °
Cap/Sagittarids Jan 13-Feb 04 Feb 02 312.5 299 -15 11h-14h 09h-14h medium
chi-Capricornids Jan 29-Feb 28 Feb 14 324.7 315 -24 10h-13h 08h-15h low
Piscids (April) Apr 08-Apr 29 Apr 20 030.3 007 +7 07h-14h 08h-13h low
delta-Piscids Apr 24-Apr 24 Apr 24 034.2 011 +12 07h-14h 08h-13h low
epsilon-Arietids Apr 24-May 27 May 08 048.7 044 +21 08h-15h 10h-14h low
Arietids (May) May 04-Jun 06 May 16 055.5 037 +18 08h-15h 09h-13h low
omikron-Cetids May 05-Jun 02 May 19 059.3 028 -4 07h-13h 07h-13h medium
Arietids May 22-Jul 02 Jun 07 076.7 044 +24 06h-14h 08h-12h high
zeta-Perseids May 20-Jul 05 Jun 09 078.6 062 +23 07h-15h 09h-13h high
beta-Taurids Jun 05-Jul 17 Jun 28 096.7 086 +19 08h-15h 09h-13h medium
gamma-Leonids Aug 14-Sep 12 Aug 25 152.2 155 +20 08h-16h 10h-14h low
Sextantids Sep 09-Oct 09 Sep 27 184.3 152 0 06h-12h 06h-13h medium
Useful addresses
For more information on observing techniques, and when submitting results, please contact the appropriate IMO Commission Director:
Fireball Data Center : André Knöfel, Saarbrückerstraße 8,
(FIDAC) D-40476 Düsseldorf, Germany.
(e-mail: fidac@imo.net)
Photographic Commission: Marc de Lignie, Prins Hendrikplein 42,
NL-2264 SN Leidschendam, the Netherlands.
(e-mail: photo@imo.net)
Radio Commission: Temporarily vacant
(e-mail: radio@imo.net)
Telescopic Commission: Malcolm Currie, 660 N'Aohoku Place,
Hilo, HI 96720, U.S.A.
(e-mail: tele@imo.net)
Video Commission: Sirko Molau, Weidenweg 1,
D-52074 Aachen, Germany
(e-mail: video@imo.net)
Visual Commission: Rainer Arlt, Friedentraße 5,
D-14109 Berlin, Germany
(e-mail: visual@imo.net)
or contact IMO's Homepage in the World-Wide-Web: http://www.imo.net/
For further details on IMO membership, please write to:
Ina Rendtel, IMO Treasurer, Mehlbeerenweg 5,
D-14469 Potsdam, Germany.
(e-mail: treasurer@imo.net)
Please try to enclose return postage when writing to any IMO officials, either in the form of stamps (same country only) or as an International Reply Coupon (I.R.C. - available from main postal outlets). Thank you!