                       International Meteor Organization

                          1993 Meteor Shower Calendar
                          ===========================

compiled by Alastair McBeath
based on contributions from Malcolm Currie, Dieter Heinlein, Andre Knoefel,
and Ralf Koschack.

prepared for Usenet and Compuserve by Andre Knoefel

                                  Introduction
                                  ============

Welcome to the 1993 International Meteor Organization (IMO) Meteor Calendar.
Inside are presented notes on some of the more impressive, interesting, or
favorably-placed meteor showers of the year, together with tables featuring
details on all the showers currently known to the IMO which produce definite
photographic, radio, telescopic, or visual activity. Although ideally meteor
data should be collected at all times when conditions permit throughout the
year, such protracted monitoring is often not possible, thus the Calendar
provides a ready means of helping to determine when a particular effort may be
most usefully made for those with a rather restricted observing schedule.

The IMO aims 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
solely by the continued support of many people across the whole world that our
first steps towards constructing a true and 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 have long been popular, and allow nightly
meteor coverage (weather permitting), although both suffer considerably from
the presence of moonlight. Telescopic observations are far less popular, though
they provide data for meteors fainter than the visual limit, and permit
accurate plotting of meteor paths, from which the identification, position,
size, and structure of shower radiants can be derived. A telescope or
binoculars can readily be used to watch the low activity visual streams---many
of which yield far more telescopic meteors than naked-eye ones---as well as the
major showers. 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. Again, both major and
minor night-time streams can be followed as well as a number of known daytime
showers, not to mention all those which may still await discovery.

Remember that all of the above modes also allow the monitoring of the
continuous background flux of sporadic meteors. Though often treated as of
lesser regard than the showers, the sporadics give an essential calibration for
all other activities, and are furthermore a fascinating subject of study on
their own. 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!

                             Highlights of the year
                             ======================

In this section, we look at some of the showers especially suitable for
observation this year. Those not dealt with are largely omitted as their main
maxima are badly affected by moonlight, although for once, most major streams
are largely moon-free. Remember that radio can still be employed to procure
results even from moonlit showers, however. Information on special projects,
new and suspected showers can be found in the IMO's bimonthly journal WGN,
which should be regularly consulted for the latest news on all matters
meteoric.



Quadrantids
-----------

Active: January 1--5
Maximum:  January 3, 10h UT (lambda=283.13deg)
ZHR = 110
Radiant : alpha=230deg, delta=+49deg
Delta\alpha=+0.8deg, Delta\delta=-0.2deg
diameter: 5deg
V = 41 km/s
r = 2.1 (variable)
TFC: alpha=242deg, delta=+75deg and alpha=198deg, delta=+40deg (beta>40deg N)

The Quadrantid maximum will suffer somewhat from a waxing gibbous Moon in
eastern Aries and western Taurus in 1993, but northern hemisphere observers
should still have an hour or two of dark sky available near and after moonset
and before dawn, since the shower radiant is at a useful elevation only in the
second half of the night. The shower cannot be seen properly from the southern
hemisphere.

The maximum ZHR seems to fluctuate from year to year, though this may be a
result of data collected from too few weather--affected sites in the past, and
the situation is further complicated by the fact that mass-sorting of the
stream causes the fainter (radio and telescopic) meteors to peak up to around
14 hours before the brighter (visual and photographic) ones.

The actual maximum for any given class of meteors rarely exceeds a few hours
duration however, and can easily be missed. The time of maximum given above is
for visual observations and allows for a nodal regression of about 0.005deg per
year, but the paucity of detailed results mean the prediction may be incorrect
by up to about +/-5 hours. Observers should thus be alert well before and after
this time.

There is some evidence that the radiant size contracts markedly near the peak
and is more diffuse at other times, so telescopic and photographic work is
needed to examine this facet, but all forms of observing can be employed to
cover the stream as a whole.



Alpha-Crucids
-------------

Active: January 6-28
Maxima: January 19 (lambda=299.7deg)
ZHR = 5
Radiant : alpha=192deg, delta=-63deg
Delta\alpha=+1.1deg, Delta\delta=-0.2deg
Radiant area: alpha=10deg x delta=5deg
V = 50 km/s
r = 2.9
TFC: alpha=189deg, delta=-40deg and alpha=140deg, delta=-61deg (beta <25deg S)
     choose pairs separated by around 30deg in alpha, moving eastward through
     the shower's duration.

This poorly-known minor shower is particularly well-suited to telescopic work
(though only from the southern hemisphere). Its maximum falls just three days
before New Moon, so the opportunity to observe it in dark skies should not be
wasted.

Several sub-maxima other than that indicated above have been suggested in the
past, but only many more results will be able to clarify this situation. At the
peak, the shower's radiant lies over the dark ``Coal Sack'' nebula in Crux, and
is thus circumpolar from many southerly latitudes, but is at its highest near
dawn.



April Piscids
-------------

Active: April 8--29
Maximum: April 20 (lambda=30.3deg)
Radiant : alpha=7deg, delta=+07deg
Best observed: 50deg N: 07h-14h, 35deg S: 08h-13h

A poorly-studied daylight shower, observable by radio techniques only (even at
maximum, the radiant is barely 30deg from the Sun, ruling out other methods).
What observations do exist of the stream suggest that it may be periodic in
appearance. A moderate return seems to have occurred in 1960, but in other
years, little or nothing has been detected. As with most meteor showers at the
present time, more investigation is badly and urgently needed, and global data
can be secured thanks to the near-equator radiant.



Lyrids
------

Active: April 16--25
Maximum: April 22, 2h UT (lambda=32.1deg)
ZHR: variable---up to 90, usually 15--25
Radiant: alpha=271deg, delta=+34deg
Delta\alpha=+1.1deg, Delta\delta=0.0deg
diameter: 5deg
V = 49 km/s
r = 2.9
TFC: alpha=262deg, delta=+16deg and alpha=282deg, delta=+19deg (beta >10deg S)

Though best viewed from the northern hemi-\break sphere, the Lyrids are
observable from most sites either north or south of the equator, and are
suitable for all forms of observation. Maximum rates are attained for only
about an hour or two at best, and can be rather erratic at times. In most
years, activity of between 15--25 meteors per hour is seen, but on occasion
much higher rates are noted. The most recent such event was in 1982 when
American observers recorded a very short-lived peak ZHR of 90. This
unpredictability means the Lyrids are always a shower to watch, since we cannot
tell when another unusual return may happen.

As the shower's radiant rises during the night, post-midnight watches are
necessary to view the highest activity. In 1993, the Visual Commission predicts
a peak favoring European and North African locations, though the maximum time
may be somewhat different to this due to variations in the stream, so all
observers should be alert. With New Moon on April 21, this shower could
scarcely be more favorable.



Pi-Puppids
----------

Active: April 15--28
Maximum: April 23 (lambda=33.3deg)
ZHR : periodic---up to around 40
Radiant: alpha=110deg, delta=-45deg
Delta\alpha=+0.6deg, Delta\delta=-0.2deg
diameter: 5deg
V = 18 km/s
r = 2.0
TFC: alpha=135deg, delta=-55deg and alpha=105deg, delta=-25deg (beta <20deg N)

This is a young stream produced by Comet P/Grigg-Skjellerup, and shower
activity has only been detected from it since 1972. Notable short-lived shower
maxima of around 40 meteors per hour occurred in 1977 and 1982---both years in
which the parent comet was at perihelion---but up to 1982, little activity was
seen at other times.

In 1983 however, a ZHR of about 13 was recorded, perhaps suggesting that the
stream has begun to spread further along the comet's orbit, as theory predicts,
so that even though Comet Grigg-Skjellerup was at perihelion in July 1992,
there is still the possibility of observing a shower from it this year.

The Pi-Puppids are best-seen from the southern hemisphere, with useful
observations possible up to roughly local midnight. So far, visual and radio
data have been collected on the shower, but the slow, bright nature of the
meteors make them ideal photographic subjects too. No telescopic data have been
reported in detail as yet either, though April's New Moon means any shower
return can be fully covered by all these techniques with the benefit of a dark
sky.



June Daylight Radio Streams
---------------------------

* Arietids:
  Active: May 22--July 2
  Maximum: June 7 (lambda=76.7)
  ZHR = 60
  Radiant : alpha=044deg, delta=+24deg
  Delta\alpha=+0.5deg, Delta\delta=+0.4deg
  diameter: 3deg
  V = 37 km/s
  Best observed: 50deg N: 06h--14h, 35deg S: 08h--12h

* Zeta-Perseids:
  Active: May 20--July 5
  Maximum: June 9 (lambda=78.6)
  ZHR = 40
  Radiant: alpha=062deg, delta=+23deg,
  Delta\alpha=+1.1deg,  Delta\delta=+0.4deg
  V = 29 km/s
  Best observed: 50deg N: 07h--15h, 35deg S: 09h--13h

* Beta-Taurids:
  Active: June 5--July 17
  Maximum: June 28 (lambda=96.7)
  ZHR = 25
  Radiant} : alpha=086deg, delta=+19deg
  Delta\alpha=+0.6deg,  Delta\delta=+0.3deg
  diameter: 3deg--7deg
  V = 30 km/s
  Best observed: 50deg N: 08h--15h, 35deg S:  09h--13h

These are three of the most active daylight streams of the year, and as such
are observable chiefly by radio means, though other observers from about the
northern tropics southwards may be fortunate enough to spot a few stream
members soon after dusk or shortly before dawn by visual methods. All three
were discovered by radio detectors at Jodrell Bank in England in 1947, and all
have been observed by other professional radar meteor projects since that time.
However, little routine monitoring of the showers' behavior has been carried
out on a year-by-year basis, so there is still much to learn.



Alpha-Lyrids
------------

Active: July 9--20
Maximum: July 15 (lambda=113deg)
Radiant : alpha=281deg, delta=+38deg
diameter: 2deg
V = approx 50 km/s
TFC: alpha=310deg, delta=+15deg and alpha=254deg, delta=+14deg (beta >10deg S)

Observations of this telescopic shower---visual rates are usually so low as to
be indistinguishable from the sporadic background---are needed on a regular
basis, since at its discovery by Czechoslovak and Soviet observers in 1958, it
was the most active telescopic shower, with average rates about 25 meteors per
hour in larger binoculars. In 1969, activity was also good, but recently the
level has been much lower. Whether this is due to the stream moving away from
the Earth, or to a periodic nature, is unknown. Northern hemisphere observers
are best able to cover the shower, with the radiant high in the sky all night,
and the waning crescent Moon at the shower's predicted peak will give no real
trouble.

Perseids
--------

Active: July 17--August 24
Maxima: August 12, 4h UT (lambda=139.6deg) and 15h UT (lambda=140.1)
ZHR = 95
Radiant : alpha=46deg, delta=+58deg
Delta\alpha, Delta\delta: see Table 4
diameter: 5deg
V = 59 km/s
r= 2.6
TFC: alpha=019deg, delta=+38deg and alpha=348deg, delta=+74deg
     before 2h local time
     alpha=043deg, delta=+38deg and alpha=073deg, delta=+66deg
     after 2h local time (beta >20deg N)

In 1991, a short-lived outburst from the Perseids was detected visually and
photographically from sites in Eastern Asia and by radio observers in other
parts of the world. This event coincided almost perfectly with the time of the
shower's first peak, discovered by the IMO from its analysis of 1988
observations.

The times of both peaks are given above for 1993, neither falling too favorably
for land observers in the northern hemisphere this year, but all meteor workers
at suitable sites should be alert in case any other unusual activity occurs at
times away from these maxima. Telescopic observers using small binoculars
should check for possible sub-radiants not detectable visually, as these may
tie in with the shower's activity profile variations.

Another important aspect of the shower which often receives little attention is
the decline in activity after the best rates are achieved. As the Moon is at
Last Quarter on August 10 this year, there is an excellent opportunity to cover
this period in detail in moon-free conditions. Standard IMO visual watches for
low-rate circumstances, or telescopic observations (fainter Perseids are
usually more abundant in this declining phase), should be carried out from
about August 14 or so though to the shower's end for this purpose.



Kappa-Cygnids
-------------

Active: August 3--31
Maximum: August 18 (lambda=145.7deg)
ZHR = 5
Radiant: alpha=286deg, delta=+59deg
diameter: 6deg
V = 25 km/s
r = 3.0
TFC: alpha=305deg, delta=+40deg and alpha=240deg, delta=+60deg (beta > 00deg)

New Moon on August 17 almost ideally favors this minor shower this year, though
it can be considered accessible only to watchers north of the equator. Its r-
value suggests telescopic observers may benefit from its presence, though
visual and photographic workers should note that occasional slow fireballs from
this source have been reported too.

There has been some suggestion of a variation in its activity at times, perhaps
coupled with a periodicity in fireball sightings, but we are a long way from
even beginning to understand all the nuances of this stream---provide us with
more data, please!



Puppid/Velids
-------------

Active: September 28--December 30
Maxima: several
Radiant: see Table 5
diameter: 10deg
V = 41 km/s
r = 2.9
TFC: alpha=90deg -- 150deg, delta=-20deg -- -60deg
     choose pairs of fields separated by about 30deg in alpha moving
     eastwards as the shower progresses

* Lambda-Velids II:
  Active: January 18--26
  Maximum: January 21 (lambda=301.7deg)
  Radiant: alpha=133deg, delta=-46deg
  Delta\alpha=+0.7deg, Delta\delta=-0.2deg
  diameter: 5deg
  V = 35 km/s
  r = 3.0
  TFC: As Puppid/Velids

This is an extremely complex system of streams, visible primarily to those
south of the equator. Up to ten possible sub-streams have been identified,
several of these with radiants so closely clustered together that visual
observations are incapable of sensibly separating them, hence the somewhat
vague Puppid/Velid details above. Telescopic reports should be more helpful in
this regard.

Several of the more readily-identified or prominent streams also feature
individually in Table 1, but the best-placed of any in 1993 is the Lambda-
Velids II, whose peak falls virtually at New Moon in January. Activity from
these showers can be followed for almost the entire night from suitable
locations, though rates are generally low. A series of maxima seem to occur in
early to mid December, when higher ZHRs may be recorded, and some bright
fireballs may be seen around this period too.

The complex may well be associated with asteroid 2102 Tantalus, perhaps giving
observers in December the chance to see meteors produced by two asteroids---the
Puppid/Velids and the Geminids. Observers should waste no clear nights near New
Moon from late September to late January to obtain plenty of results on these
meteors.



Orionids
--------

Active: October 2--November 7
Maximum: October 21 (lambda=208.4deg)
ZHR = 25
Radiant: alpha=95deg, delta=+16deg
Delta\alpha=+1.2deg,  Delta\delta=+0.1deg
diameter: 10deg
V = 66 km/s
r = 2.9
TFC: alpha=100deg, delta=+39deg and alpha=075deg, delta=+24deg (beta >40deg N)
     alpha=080deg, delta=+01deg and alpha=117deg, delta=+01deg (beta <40deg N)

With its near-equator radiant, the Orionids provide a moderate spectacle for
much of the globe, and observations can be carried out from around midnight or
a little before from most places. The waxing crescent Moon will present few
difficulties near the main maximum (there are several sub-maxima which are
usually noted too, in a similar fashion to the linked stream the
Eta-Aquarids both of which are believed to have originated in Comet P/Halley),
and some dark-sky watching should be possible after moonset until about October
24 or 25, depending on location.

The radiant itself is complex and benefits from telescopic watching, as the
structure and sub-maxima are extremely difficult to pin down by visual or
photographic data alone. This is particularly true as the r-value may vary
quite considerably at different points within the sub-maxima. A good
geographical spread of observers is also necessary to ensure as complete
coverage as possible.

Like their May counterpart the Eta-Aquarids, Orionid meteors are swift, can be
bright and are often trained, so they well repay the effort needed to see them.



Taurids
-------

* Taurids South:
  Active: September 15--November 25
  Maximum: November 3 (lambda=220.7deg)
  ZHR = 10
  Radiant: alpha=050deg, delta=+14deg,
  Delta\alpha, Delta\delta: see Table 6
  Radiant area: alpha=10deg x delta=5deg
  V = 27 km/s
  r = 2.3
  TFC: pairs of fields 15deg east or west of the double radiant at
  delta=+17deg (beta >30deg N) or delta=+06deg (beta >40deg S)

* Taurids North:
  Active: September 13--November 25
  Maximum: November 13 (lambda=230.7deg)
  ZHR = 8
  Radiant: alpha=060deg, delta=+23deg
  Delta\alpha, Delta\delta: see Table 6
  Radiant area: alpha=10deg x delta=5deg
  V = 29 km/s
  r = 2.3
  TFC: as Southern Taurids

These two streams form a complex associated with Comet P/Encke. Both radiants
are difficult to define precisely, and usually only visual or telescopic
plotting permits easy differentiation between the two showers. Further work of
this sort will no doubt be beneficial to our understanding of the Taurids, and
the brightness of many shower members coupled with their low relative velocity
makes them ideal targets for photography.

Combined activity from these sources remains at about 3--4 meteors per hour
from roughly late October to late November, while both maxima are broad and
flat, lasting for about a week or more with nearly constant ZHRs. This steady
activity and slow apparent speed means that these are excellent showers for
newcomers to practice their visual meteor plotting techniques on, choosing
areas of sky some 20deg -- 30deg east or west of the radiants.

This year, lunar conditions are especially conducive to watching the Northern
Taurid peak, with New Moon on November 13. The near-ecliptic radiant positions
for both shower branches mean all meteoricists can observe the streams, though
the northern hemisphere is rather more favored, however, with suitable radiant
zenith distances for most of the night. Even in the southern hemisphere,
though, a good 3--5 hours around local midnight sees the constellation of
Taurus well above the horizon from many areas.



Leonids
-------

Active: November 14--21
Maximum: November 17, 20h UT (lambda=235.71deg)
ZHR: periodic---up to storm levels, recently 10--15
Radiant : alpha=152deg, delta=+22deg
Delta\alpha=+0.7deg, Delta\delta=-0.4deg
diameter: 5deg
V = 71 km/s
r = 2.5
TFC: alpha=140deg, delta=+35deg and alpha=129deg, delta=+06deg (beta >35deg N)
  or alpha=156deg, delta=-03deg and alpha=129deg, delta=+06deg (beta <35deg N)

The Leonid stream is perhaps most famous for its periodic storms occurring at
roughly 33-year intervals when its associated comet, P/Tempel-Tuttle, returns
to perihelion. This situation is due to happen again in the years 1998--2000,
and Leonid activity is expected to increase in the next few years as the comet
approaches. Clearly, we have the best opportunity ever to follow these changes
in the coming years more fully than has been previously possible, and to take
advantage of these circumstances in a special International Leonid Watch
project that has been set up with IMO help to coordinate world-wide
professional and amateur Leonid studies. All observing methods should be
pursued to ensure that no detail is missed, with data collection already begun
in 1991, intended to continue into the next century.

In 1993, circumstances are excellent for all watchers whether north or south of
the equator, since the Moon is a waxing crescent throughout the shower's
activity, and will have set by the time the radiant rises, around midnight or
so, from most latitudes.



December Monocerotids
---------------------

Active: November 27--December 17
Maximum: December 10 (lambda=258.7deg)
ZHR = 5
Radiant: alpha=100deg, delta=+14deg
Delta\alpha=+1.2deg, Delta\delta=0.0deg
diameter: 5deg
V = 42 km/s
r = 3.0
TFC: alpha=088deg, delta=+20deg and alpha=135deg, delta=+48deg (beta >40deg N)
  or alpha=120deg, delta=-03deg and alpha=084deg, delta=+10deg (beta <40deg N)

Visual rates from this shower are usually low, and although it can be observed
by radio, it is telescopic observers who are encouraged to particularly cover
the stream at present. Details concerning the shower are rather uncertain, and
even the maximum data and radiant position may have changed somewhat from the
above values.

The Telescopic Commission Director suggests the peak may now occur on December
16 (lambda approx. 264deg) from a radiant at alpha=117deg, delta=+20deg. A good
data set would undoubtedly help to resolve this. Observable for the major part
of the night from much of the globe, the Monocerotids are free from moonlight
in 1993 near the peak, as New Moon falls on December 13.



Geminids
--------

Active: December 7--17
Maximum: December 13, 22h UT (lambda=262.0deg)
ZHR = 110
Radiant: alpha=112deg, delta=+33deg
Delta\alpha=+1.0deg, Delta\delta=-0.1deg
diameter: 4deg
V = 35 km/s
r = 2.6
TFC: alpha=087deg, delta=+20deg and alpha=135deg, delta=+48.5deg
     before 23h local time
     alpha=087deg, delta=+20deg and alpha=129deg, delta=+20deg
     after 23h local time (beta >40deg N)
  or alpha=120deg, delta=-03deg and alpha=084deg, delta=+09.5deg
     (beta <40deg N)

Probably the finest annual shower presently observable, the entire activity
period is free from lunar interference this year, providing a splendid
opportunity to observe throughout the shower for once. Southern hemisphere
observers suffer to a degree, as the radiant is low or below the horizon before
midnight, but this is a splendid stream of often bright, medium-speed meteors,
and well-rewards even these watchers. In 1990, the Geminid maximum occurred at
lambda=262.25deg, and if this repeats in 1993, the shower will reach a peak on
December 14 around 3h UT, rather than that given above. In either case however,
European and African observers will be the fortunate witnesses, assuming no
more recent changes in the stream have taken place. Some mass-sorting across
the stream means that fainter telescopic meteor rates are at their highest
almost $1^\g$ of solar longitude ahead of the visual peaks mentioned earlier,
and telescopic results show these meteors radiate from an elongated region,
with up to three possible sub-centers. Further data for this topic would
naturally be most valuable, though all forms of observing method can be
employed for the Geminids.




                                 Abbreviations
                                 =============

- alpha, delta, Delta\alpha, Delta\delta: Coordinates for a shower's radiant
         position, usually at maximum; alpha is right ascension, and delta is
         declination. Delta indicates the change in either alpha or delta per
         day.
- r : Poplation 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, given for the equinox 2000.0.
- V : Atmospheric or apparent meteoric velocity given in km/s.
- ZHR: Zenithal Hourly Rate, a calculated maximum number of meteors an ideal
         observer would see in a perfectly clear skies with the  shower radiant
         overhead. This figure is given in terms of meteors per hour.
- TFC: suggested telescopic field centers. beta is the observer's latitude
         (``<'' means ``south of'' and ``>'' means ``north of''). Pairs of
         fields must be observed, alternating about every half hour, so that
         the positions of radiants can be defined.



                                     Tables
                                     ======

Table 1 -- Working list of visual meteor showers. Streams marked with an
           asterisk only produce the indicated ZHR in certain years, and
           otherwise produce much lower activity. Contact the IMO's Visual
           Commission for more information.



Shower                    Activity       Maximum        Radiant
                                         Date   lambda  alpha delta Diam

                                                 (deg)  (deg) (deg) (deg)

Quadrantids               Jan 01-Jan 05  Jan 03  283.1   230  +49     5
Pi-Puppids II (3)         Jan 06-Jan 14  Jan 10  290.7   113  -43     5
Delta-Cancrids            Jan 05-Jan 24  Jan 17  296.7   130  +20    10/5
Alpha-Crucids             Jan 06-Jan 28  Jan 19  299.7   192  -63    10/5
Lambda-Velids II (3)      Jan 18-Jan 26  Jan 21  301.7   133  -46     5
Alpha-Carinids            Jan 24-Feb 09  Jan 31  311.7    95  -54     5
Virginids                 Feb 01-May 30    several       195  -04   15/10
Theta-Centaurids          Jan 23-Mar 12  Feb 01  312.7   210  -40     6
Alpha-Centaurids *        Jan 28-Feb 21  Feb 07  318.7   210  -59     4
Omicron-Centaurids        Jan 31-Feb 19  Feb 11  322.7   177  -56     6
Delta-Leonids             Feb 05-Mar 19  Feb 15  326.7   159  +19     8
Gamma-Normids             Feb 25-Mar 22  Mar 14  353.7   249  -51     5
Beta-Pavonids             Mar 11-Apr 16  Apr 06  017.2   308  -63   10/15
Scorpid/Sagittarids (1)   Apr 15-Jul 25    several       260  -30   15/10
Lyrids *                  Apr 16-Apr 25  Apr 22  032.1   271  +34     5
Pi-Puppids *              Apr 15-Apr 28  Apr 23  033.3   110  -45     5
Alpha-Bootids             Apr 14-May 12  Apr 26  036.7   218  +19     8
Eta-Aquarids              Apr 19-May 28  May 03  043.1   336  -02     4
Alpha-Scorpids (2)        Mar 26-May 12  May 03  043.4   240  -27     5
Ophiuchids N (2)          Apr 25-May 31  May 10  049.7   249  -14     5
Beta-Corona Australids(2) Apr 23-May 30  May 15  054.7   284  -40     5
Kappa-Scorpids (2)        May 04-May 27  May 19  058.9   267  -39     5
Ophiuchids S (2)          May 13-May 26  May 20  059.8   258  -24     5
Omega-Scorpids (2)        May 23-Jun 15  Jun 04  074.2   243  -22     5
Chi-Scorpids (2)          May 24-Jun 20  Jun 05  075.2   248  -14     6
Gamma-Sagittarids (2)     May 22-Jun 13  Jun 06  076.1   272  -28     6
Theta-Ophiuchids (2)      Jun 04-Jul 15  Jun 13  082.4   267  -20     5
Lyrids (Jun)              Jun 11-Jun 21  Jun 16  085.2   278  +35     5
Bootids (Jun)             Jun 26-Jun 30  Jun 28  096.3   219  +49     8
Lambda-Sagittarids (2)    Jun 05-Jul 25  Jul 01  099.6   276  -25     6
Pegasids                  Jul 07-Jul 11  Jul 09  107.7   340  +15     5
Phoenicids (Jul)          Jun 24-Jul 18  Jul 15  112.7   021  -43     7
Piscis Austrinids         Jul 09-Aug 17  Jul 28  125.7   341  -30     5
Delta-Aquarids S          Jul 08-Aug 19  Jul 28  125.7   339  -16     5
Alpha-Capricornids        Jul 03-Aug 25  Jul 29  126.7   307  -10     8
Iota-Aquarids S           Jul 15-Aug 25  Aug 03  131.7   333  -15     5
Delta-Aquarids N          Jul 15-Aug 25  Aug 12  139.7   337  -05     5
Perseids                  Jul 17-Aug 24  Aug 12  139.9   046  +58     5
Kappa-Cygnids             Aug 03-Aug 31  Aug 18  145.7   286  +59     6
Iota-Aquarids N           Aug 11-Sep 20  Aug 20  147.7   327  -06     5
Pi-Eridanids              Aug 20-Sep 05  Aug 29  155.7   052  -15     6
Alpha-Aurigids            Aug 24-Sep 05  Sep 01  158.6   084  +42     5
Delta-Aurigids            Sep 05-Oct 10  Sep 09  166.7   060  +47     5
Piscids S                 Aug 15-Oct 14  Sep 20  177.7   008   00     8
Kappa-Aquarids            Sep 08-Sep 30  Sep 21  178.7   339  -02     5
Puppid/Velids             Sep 28-Dec 30    several        Table 5    10
Capricornids (Oct)        Sep 20-Oct 14  Oct 02  189.7   303  -10     5
Sigma-Orionids            Sep 10-Oct 26  Oct 04  191.7   086  -03     5
Draconids *               Oct 06-Oct 10  Oct 10  197.0   262  +54     5
Epsilon-Geminids          Oct 14-Oct 27  Oct 20  206.7   104  +27     5
Orionids                  Oct 02-Nov 07  Oct 21  208.4   095  +16    10
Taurids S                 Sep 15-Nov 25  Nov 03  220.7   050  +14    10/5
Taurids N                 Sep 13-Nov 25  Nov 13  230.7   060  +23    10/5
Leonids *                 Nov 14-Nov 21  Nov 17  235.7   152  +22     5
Alpha-Monocerotids        Nov 15-Nov 25  Nov 21  239.4   117  -06     5
Chi-Orionids              Nov 26-Dec 15  Dec 02  250.0   082  +23     8
Phoenicids (Dec) *        Nov 28-Dec 09  Dec 06  254.3   018  -53     5
Sigma-Puppids II (3)      Nov 27-Dec 12  Dec 06  254.7   102  -45     5
Monocerotids (Dec)        Nov 27-Dec 17  Dec 10  258.7   100  +14     5
Sigma-Hydrids             Dec 03-Dec 15  Dec 11  259.7   127  +02     5
Geminids                  Dec 07-Dec 17  Dec 14  262.0   112  +33     4
Coma Berenicids           Dec 12-Jan 23  Dec 19  267.7   175  +25     5
Ursids *                  Dec 17-Dec 26  Dec 22  270.9   217  +75     5
Tau-Puppids (3)           Dec 19-Dec 30  Dec 23  272.0   104  -50     5



Shower                     Drift         V      r     ZHR
                           Delta
                           alpha delta
                           (deg) (deg)  (km/s)

Quadrantids                +0.8  -0.2    41    2.1    110
Pi-Puppids II (3)          +0.4  -0.2    35    3.0
Delta-Cancrids             +0.9  -0.1    28    3.0     5
Alpha-Crucids              +1.1  -0.2    50    2.9     5
Lambda-Velids II (3)       +0.7  -0.2    35    3.0
Alpha-Carinids                           25    2.5
Virginids                    Table 2     30    3.0     5
Theta-Centaurids           +1.1  -0.2    60    2.6
Alpha-Centaurids *         +1.2  -0.3    56    2.0    25+
Omicron-Centaurids         +1.0  -0.3    51    2.8
Delta-Leonids              +0.9  -0.3    23    3.0     3
Gamma-Normids              +1.1  +0.1    56    2.4     8
Beta-Pavonids              +1.2  +0.1    59    2.6    13
Scorpid/Sagittarids (1)      Table 3     30    2.3    10
Lyrids *                   +1.1   0.0    49    2.9    90
Pi-Puppids *               +0.6  -0.2    18    2.0    40
Alpha-Bootids              +0.9  -0.1    20    3.0     3
Eta-Aquarids               +0.9  +0.4    66    2.7    50
Alpha-Scorpids (2)         +0.9  -0.1    35    2.5    10
Ophiuchids N (2)           +0.9  -0.1    30    2.9
Beta-Corona Australids(2)  +0.9  -0.1    45    3.1
Kappa-Scorpids (2)         +0.9   0.0    45    2.8
Ophiuchids S (2)           +0.9  -0.1    30    2.9
Omega-Scorpids (2)         +0.9  -0.1    23    3.0
Chi-Scorpids (2)           +0.9  -0.1    21    3.1
Gamma-Sagittarids (2)      +0.9   0.0    29    2.9
Theta-Ophiuchids (2)       +0.9   0.0    27    2.8
Lyrids (Jun)               +0.8   0.0    31    3.0     5
Bootids (Jun)                            14    3.0     2
Lambda-Sagittarids (2)     +0.9   0.0    23    2.6
Pegasids                   +0.8  +0.2    70    3.0     8
Phoenicids (Jul)           +1.0  +0.2    47    3.0
Piscis Austrinids          +1.0  +0.2    35    3.2     8
Delta-Aquarids S             Table 4     41    3.2    20
Alpha-Capricornids           Table 4     23    2.5     8
Iota-Aquarids S              Table 4     34    2.9     3
Delta-Aquarids N             Table 4     42    3.4     5
Perseids                     Table 4     59    2.6    95
Kappa-Cygnids                            25    3.0     5
Iota-Aquarids N              Table 4     31    3.2     3
Pi-Eridanids               +0.8  +0.2    59    2.8
Alpha-Aurigids             +1.1   0.0    66    2.5    15
Delta-Aurigids             +1.0  +0.1    64    3.0     7
Piscids S                  +0.9  +0.2    26    3.0     3
Kappa-Aquarids             +1.0  +0.2    16    3.0     3
Puppid/Velids                Table 5     41    2.9
Capricornids (Oct)         +0.8  +0.2    15    2.8     3
Sigma-Orionids             +1.2   0.0    65    3.0     3
Draconids *                              20    2.6   storm
Epsilon-Geminids           +1.0   0.0    71    3.0     5
Orionids                   +1.2  +0.1    66    2.9    25
Taurids S                    Table 6     27    2.3    10
Taurids N                    Table 6     29    2.3     8
Leonids *                  +0.7  -0.4    71    2.5   storm
Alpha-Monocerotids         +1.1  -0.1    60    2.7     5
Chi-Orionids               +1.2   0.0    28    3.0     3
Phoenicids (Dec) *         +0.8  +0.1    18    2.8    100
Sigma-Puppids II (3)       +0.3  -0.1    38    2.9
Monocerotids (Dec)         +1.2   0.0    42    3.0     5
Sigma-Hydrids              +0.7  -0.2    58    3.0     5
Geminids                   +1.0  -0.1    35    2.6    110
Coma Berenicids            +0.8  -0.2    65    3.0     5
Ursids *                                 33    3.0    50
Tau-Puppids (3)            +0.2  -0.1    33    3.0


(1) Radiation area of the Scorpid-Sagittarid complex. Observers north of 30deg N
    should only take into account this area.

(2) Major components of the Sco-Sgr complex, to be analyzed by observers south
    of 30deg N only.

(3) Major components of the Puppid/Velid complex.





Table 2 - Virginid complex radiant center motion.

Date   alpha delta  Date   alpha delta  Date   alpha delta  Date   alpha delta
       (deg) (deg)         (deg) (deg)         (deg) (deg)         (deg) (deg)

Feb 03  159   +15   Mar 05  182   +01   Apr 04  200   -06   May 04  211   -11
    13  167   +09       15  189   -02       14  204   -08       14  214   -12
    23  174   +05       25  195   -04       24  208   -09       24  217   -13




Table 3 - Scorpid/Sagittarid complex radiant center motion.

Date   alpha delta  Date   alpha delta  Date   alpha delta  Date   alpha delta
       (deg) (deg)         (deg) (deg)         (deg) (deg)         (deg) (deg)

Apr 15  224   -18   May 05  236   -25   Jun 04  260   -30   Jul 04  288   -27
    25  230   -22       15  243   -27       14  269   -30       14  297   -24
                        25  251   -29       24  279   -28       24  306   -20





Table 4 - Radiant drifts for the Alpha-Capricornids, the Delta-Aquarids South
          and North, the Iota-Aquarids South and North, and the Perseids.

Date    Alpha-Cap   Delta-Aqr S Delta-Aqr N Iota-Aqr S  Iota-Aqr N  Perseids
        alpha delta alpha delta alpha delta alpha delta alpha delta alpha delta
        (deg) (deg) (deg) (deg) (deg) (deg) (deg) (deg) (deg) (deg) (deg) (deg)

Jul 05   290   -14   321   -21
    15   296   -13   329   -19   316   -10   311   -18               012   +51
    25   303   -11   337   -17   323   -09   322   -17               023   +54
Aug 05   312   -09   345   -14   332   -06   334   -15               037   +57
    15   318   -06   352   -12   339   -04   345   -13   322   -07   050   +59
    25   324   -04               347   -02   355   -11   332   -05   065   +60
Sep 05                                       343   -03
    15                                       353   -02





Table 5 - Puppid/Velid complex radiant center motion.

Date   alpha delta  Date   alpha delta  Date   alpha delta  Date   alpha delta
       (deg) (deg)         (deg) (deg)         (deg) (deg)         (deg) (deg)

                    Oct 10  107   -44   Nov 10  116   -44   Dec 10  132   -44
                        20  110   -44       20  120   -44       20  137   -44
Sep 30  104   -44       30  113   -44       30  126   -44       30  141   -44





Table 6 - Radiant positions for the Taurids South and North.

Date      Taurids S       Taurids N
         alpha delta     alpha delta
         (deg) (deg)     (deg) (deg)

Sep 15    011   +01       008   +06
    20    015   +02       012   +07
    30    023   +05       021   +11
Oct 10    031   +08       029   +14
    20    039   +11       038   +17
    30    047   +13       047   +20
Nov 10    056   +15       058   +22
    20    064   +16       067   +24
    25    069   +17       072   +24




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 45deg 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. For more details, please contact
          the IMO's Radio Commission.

Shower           Activity       Maximum        Radiant      Best Observed   ZHR
                                Date   lambda  alpha delta
                                        (deg)  (deg) (deg)  50deg N 35deg S

Cap/Sagittarids  Jan 13-Feb 04  Feb 01  312.5   299   -15   11h-14h 09h-14h  15
Chi-Capricornids Jan 29-Feb 28  Feb 13  324.7   315   -24   10h-13h 08h-15h   5
Piscids (Apr)    Apr 08-Apr 29  Apr 20  030.3   007   +07   07h-14h 08h-13h
Delta-Piscids    Apr 24-Apr 24  Apr 24  034.2   011   +12   07h-14h 08h-13h
Epsilon-Arietids Apr 24-May 27  May 09  048.7   044   +21   08h-15h 10h-14h
Arietids (May)   May 04-Jun 06  May 16  055.5   037   +18   08h-15h 09h-13h
Omicron-Cetids   May 05-Jun 02  May 20  059.3   028   -04   07h-13h 07h-13h  15
Arietids         May 22-Jul 02  Jun 07  076.7   044   +24   06h-14h 08h-12h  60
Zeta-Perseids    May 20-Jul 05  Jun 09  078.6   062   +23   07h-15h 09h-13h  40
Beta-Taurids     Jun 05-Jul 17  Jun 28  096.7   086   +19   08h-15h 09h-13h  25
Gamma-Leonids    Aug 14-Sep 12  Aug 25  152.2   155   +20   08h-16h 10h-14h
Sextantids       Sep 09-Oct 09  Sep 27  184.3   152    00   06h-12h 06h-13h  30


Table 8 - Lunar phases for 1993

First Quarter J 01 J 30 M 01 M 31 A 29 M 28 J 26 J 26 A 24 S 22 O 22 N 21 D 20
Full Moon     J 08 F 06 M 08 A 06 M 06 J 04 J 03 A 02 S 01 S 30 O 30 N 29 D 28
Last Quarter  J 15 F 13 M 15 A 13 M 13 J 12 J 11 A 10 S 09 O 08 N 07 D 06
New Moon      J 22 F 21 M 23 A 21 M 21 J 20 J 19 A 17 S 16 O 15 N 13 D 13




                                Useful addresses
                                ================

For more information on observing techniques, and when submitting results,
please contact the appropriate IMO Commission Director:

Fireball Data Center :    A. Knoefel, Saarbrueckerstrasse 8,
(FIDAC)                   D-40476 Duesseldorf, Germany.
                          (e-mail: starex@tron.gun.de)

Photographic Commission:  D. Heinlein, Lilienstrasse 3,
                          D-86156 Augsburg, Germany.
                          (e-mail: heinlein@dhdmpi5.bitnet)

Radio Commission:         J. Van Wassenhove, 's Gravenstraat 66,
                          B-9810 Nazareth, Belgium.

Telescopic Commission:    M. Currie, 25 Collett Way, Grove, Wantage, Oxon.
                          OX12 0NT, UK.
                          (e-mail: mjc@astrophysics.starlink.rutherford.ac.uk)

Visual Commission:        R. Koschack, Hochwaldstrasse 12, A 131,
                          D-02763 Zittau, Germany.

For further details on IMO membership, please write to:
                          Ina Rendtel, IMO Treasurer, Gontardstrasse 11
                          D-14471 Potsdam, Germany.
                          (e-mail: rnl@babel.aip.de)

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!
 
 
 
