World of Ham Radio 1994 January

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International Meteor Organization 1994 Meteor Shower Calendar =========================== Compiled by Alastair McBeath based on contributions from Malcolm Currie, Ralf Koschack, Paul Roggemans, and Jeroen Van Wassenhove prepared for Usenet and Compuserve by Andre Knoefel Introduction ============ Welcome to the 1994 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 support of many people across the whole world that our continuing 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. Video methods are now starting to be taken up, and these have the advantages, and disadvantages, of both photographic and telescopic observing, but are certain to increase in importance in the future. 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, including this year the Quadrantids, Orionids and Geminids. 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. Alpha-Leonids ------------- Active: December 28--February 13 Maximum: uncertain, probably around January 10 or between January 24--31 ZHR = mainly telescopic Radiant : alpha=156deg, delta=+09deg V = 33 km/s TFC: alpha=140deg, delta=+37deg and alpha=151deg, delta=+22deg. Many uncertainties exist about this chiefly telescopic shower. It may be active from late December or early January and recent observations have suggested strong telescopic rates from a radiant near alpha = 140deg, delta = +17deg close to January 10. Whether this indicates two possible maxima for the shower is unknown. Due to the relative proximity of the delta-Cancrid radiant, it is important to use TFCs that will allow discrimination between the two sources. The new Moon favours checking for telescopic -- or even low visual -- rates around the January 10 "peak" in 1994, and the radiant is at a viable elevation from most sites after 22h local time. Virginids --------- Active: February 1--May 30 Maxima: several ZHR = 5 Radiant : alpha=195deg, delta=-04deg, Delta\alpha, Delta\delta: see Table 2 Radiant area: alpha=15deg x delta=10deg V = 30 km/s r = 3.0 TFC: alpha = 150deg-225deg, delta = +10deg--20deg beta <35deg N) or delta = -10deg--+20deg (beta >35deg N) choose pairs separated by around 30deg in alpha, moving eastward through the shower's duration. Many meteor workers have found streams with radiants clustered close to the ecliptic which are active at various, often overlapping, times throughout much of the year. Considering that many bodies in the solar system have orbital planes which lie close to that of the ecliptic this is not too surprising, but the clustering effect means it is frequently very difficult to separate individual components from complexes such as the Virginids. What we can state is that a number of low-activity radiants are active in Leo and Virgo in the opening month of the year, but that only careful visual plotting, telescopic and photographic observations will reveal more of the true activity which is occurring. Despite the high r-value and low ZHRs, occasional fireballs are reported giving extra interest to visual and photographic work. Several maxima are thought to exist, most of these when the radiant region is in Virgo, so although sites in both hemispheres can be used by watchers, the equatorial and southern parts of the globe are rather better-favored. The center of radiation culminates after midnight in the early stages of activity, and shortly before that time by April-May, so the times near New Moon from February to May should be fully utilized to secure plenty of results. Alpha-Centaurids ---------------- Active: January 28--February 21 Maximum: February 7 (lambda=318deg) ZHR = variable -- may reach 25+, usually 5-10 Radiant : alpha=210deg, delta=-59deg, Delta\alpha=+1.2deg, Delta\delta=-0.3deg diameter: 4deg V = 56 km/s r = 2.0 The Alpha-Centaurids are one of the main southern-hemisphere high points in the opening month of the year, producing many very bright, even fireball-class (meteors of or in excess of magnitude -3) objects. Their peak activity is most unpredictable. Generally, the best rates are only about 8 meteors per hour, but two to three hour bursts of ZHRs around 25 have occasionally been reported, most recently in 1980. When another unusual return will occur is impossible to determine, but this year the 27-day old Moon affords an excellent prospect for visually and photographically watching what does happen. Thanks to their brilliance, even a normal return makes Alpha-Centaurid meteors well worth looking out for, and almost one third regularly leave persistent glowing trains after them. Their radiant is nearly circumpolar from much of the sub-equatorial Earth, and is at a useful elevation from late evening onwards. Gamma-Normids ------------- Active: February 25--March 22 Maximum: March 14 (lambda=353.7deg) ZHR = 8 Radiant : alpha=249deg, delta=-51deg, Delta\alpha=+1.1deg, Delta\delta=+0.1deg diameter: 5deg V = 56 km/s r = 2.4 TFC: alpha=225deg, delta=-26deg and alpha=215deg, delta=-45deg (beta <15deg S) Gamma-Normid meteors are very 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 very sharp, though it has been suggested that the highest ZHR does vary, at times being scarcely noticeable. Post-midnight observing yields best results, when the radiant is rising to a reasonable elevation, and the Moon, new two days before the maximum, should present no real problems. All forms of observation can be carried out for them. Beta-Pavonids ------------- Active: March 11--April 16 Maximum: April 7, 4h UT (lambda=17.2deg) ZHR = var.--avg.: 13 Radiant : alpha=308deg, delta=-63deg, Delta\alpha=+1.2deg, Delta\delta=+0.1deg, area: alpha=10deg and delta=15deg V = 59 km/s r = 2.6 TFC: alpha=268deg, delta=-35deg and alpha=176deg, delta=-65deg (beta <10deg S) Only observable from the southern hemisphere, primarily in the second of the night as the radiant is very low before midnight, this stream's main peak suffers only slight problems from a waning cresent Moon this year. Several submaxima have been noted the past and the rates can vary considerably from one return to the next, which gives further interest. Visual and telescopic plotting of shower members is especially valuable to refine our understanding of the radiant structure, though as many stream meteors are bright, photographic observing is worthwhile too. Scorpids/Sagittarids -------------------- Active: April 15--Juli 25 Maxima: several ZHR = 10 Radiant (June 4) : alpha=260deg, delta=-30deg Delta\alpha, Delta\delta: see Table 3 Radiant area: alpha=15deg x delta=10deg V = 30 km/s r = 2.3 TFCs: 20deg north or south of the ecliptic separated by 15deg to 25deg, alpha=230deg-280deg (beta<40deg N) Many stream catalogues feature at least some of the showers from this complex, with radiants in Scorpius, Ophiuchus and Sagittarius, but very few of the component streams can be defined with certainty, hence the very diffuse radiant given here. Too little serious study of this group of showers has so far been carried out to try to resolve any but the chief maxima, although others may well exist, with varying ZHRs. Although radio and visual results would be useful, particularly visual plotting of stream members near the radiant area, telescopic and photographic work is really necessary to help properly discover the full radiant structure. Many of the meteors are bright, and some fireballs are recorded in most years, so photography is distinctly practical despite the generally low ZHRs. A glance at the negative declination for the radiant center shows the complex to be best seen from south of the equator, but activity is still visible from the northern hemisphere too, and all watchers should make full use of the New Moon periods of early to mid April, May, June and July in 1994 to obtain plenty of results on this body of streams, especially in early June, when a number of telescopic maxima may occur. As the overall radiant area culminates at roughly local midnight throughout these months, shower members should be occurring for almost the whole night. 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. Unfortunately, June is also the time of maximum Sporadic-E occurrence during the year, which can make forward-scatter observing of the maxima difficult, but it is still very important. Pegasids -------- Active: July 7--11 Maximum: July 10 (lambda=107.7deg) ZHR = 8 Radiant : alpha=340deg, delta=+15deg; Delta\alpha=+0.8deg, Delta\delta=+0.2deg diameter: 5deg V = 70 km/s r = 3.0 TFC: alpha=320deg, delta=+10deg and alpha=332deg, delta=+33deg (beta >40deg N) alpha=357deg, delta=+02deg (beta <40deg N) Watching this very short-lived minor shower is not easy, as a few cloudy nights mean its loss for visual observers, but the Moon will be just pas new for its peak this year, and all -- particularly those in the northern hemisphere -- should attempt to cover it. The shower is best-observed in the second half of the night, and the maximum ZHR may vary from year to year. Telescopic data would be especially welcomed to help in confirming the radiant position. 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 >010deg 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 waxing crescent Moon at the shower's predicted peak will give no real trouble. Perseids -------- Active: July 17--August 24 Maxima: Main maxima: August 12, 7h UT (lambda=139.45deg -- see below) and 15h UT (lambda=140.1deg) ZHR = 95 Radiant : alpha=046deg, 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) The Perseids have become the single most exciting and dynamic meteor shower recent times, with outbursts producing ZHRs of approx 400+ in both 1991 and 1992. The return of the showers parent comet P/Swift-Tuttle in late 1992 created further interest, and undoubtedly, the events of 1993 August will yield more material for speculation on the stream. Unfortunately, this dynamic nature has meant attempts to predict the peak time for the shower have become increasingly difficult, and the time given above is based on the 1992 outburst. This is naturally subject to further modification and revision after the 1993 return, and WGN will keep you fully informed as to developments, as well as what to record if very high activity is seen. Whether a further outburst can be expected in 1994 is an unknown, but all observers should be alert in case. Moonlight favours the pre- up to early post-maximum phases of the Perseids this year, and all observing techniques should be employed. Telescopic watching near the main peak is valuable in confirming or clarifying the possible multiple nature of the Perseid radiant, something not detectable visually, while a series of five-minute photographic observations of the zenith, if high activity happens, will help define the true activity, another item very difficult to determine from visual results alone. Video data would also be invaluable under these circumstances, and radio data will enable early confirmation, or detection, of a poorly-seen -- perhaps otherwise unobserved -- outburst. Alpha- and Delta-Aurigids ------------------------- * Alpha-Aurigids: Active: August 24--September 5 Maximum: September 1 (lambda=158.6deg) ZHR = 15 Radiant: alpha=084deg, delta=+42deg Delta\alpha=+1.1deg, Delta\delta=0.0deg diameter: 5deg V = 66 km/s r = 2.5 TFC: alpha=052deg, delta=+60deg alpha=043deg, delta=+39deg and alpha=023deg, delta=+41deg (beta >10deg S) * Delta-Aurigids: Active: September 5--October 10 Maximum: September 9 (lambda=166.7deg) ZHR = 7 Radiant : alpha=060deg, delta=+47deg Delta\alpha=+1.0, Delta\delta=+0.1 diameter: 5deg V = 64 km/s r = 3.0 TFC: as Alpha-Aurigids These are both essentially northern hemisphere events, and are badly in need of more observing effort. Despite occuring close to one another in time, and radiating from the same constellation, they are separate streams. The Alpha- Aurigids are the more active, with unusual bursts giving ZHRs of approx 30--40 meteors per hour reported in 1935 and 1986, but they have not been regularly observed, so other events may have been missed. The Delta-Aurigids produce lower rates generally, and have yet to be well-seen in more than an occasional year. 1n 1994, we have the opportunity to improve our knowledge of both showers, since new Moon falls on September 5, thus both maxima can be observed in dark skies for once. Telescopic data confirm the radiants -- and possibly observe the telescopic Beta-Cassiopeid shower simultaneously -- would be especially welcomed, but visual plotting and photography would be very useful too. The shower radiants are at a useful elevation from roughly 23h--00h onwards, so protracted watching is distinctly possible. 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: Choose fields on the ecliptic and approx 10deg E or W of the radiants or four fields to the NE, NW, SE and SW of the radiants (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 Southern Taurid peak, with New Moon on November 3. 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 18, 01h UT (lambda=235.55deg) 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 cordinate 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 1994, circumstances could not be worse for all watchers north or south of of the equator, since the Moon will be full in Taurus on November 18. However, the importance of obtaining data now in case unusual rates occur is high, so observers -- especially radio observers -- should be active. The radiant rises only after midnight from most latitudes. Chi-Orionids ------------ Active: November 26--December 15 Maximum: December 2 (lambda=250.0deg) ZHR = 3 Radiant: alpha=082deg, delta=+23deg, Delta\alpha=+1.2deg, Delta\delta=0.0deg diameter: 8deg V = 28 km/s r = 3.0 TFC: alpha=083deg, delta=+09deg and alpha=080deg, delta=+24deg This weak visual stream is moderately active telescopically, although a number of brighter meteors have been recorded by professional photographic patrols in the past too. The shower has a double radiant (at least), but the southern branch has been rarely detected. A combined radiant as assumed for visual work, but binocular observers should be better-able to define the true radiant structure. New Moon on December 2 coincides perfectly with the shower's peak this year, and the radiant, actually in eastern Taurus, is well-displayed for virtually the entire night for all global watchers. 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 07 017.2 308 -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 27 036.7 218 +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 10 107.7 340 +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 30 126.7 307 -10 8 Iota-Aquarids S Jul 15-Aug 25 Aug 04 131.7 333 -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 03 189.7 303 -10 5 Sigma-Orionids Sep 10-Oct 26 Oct 05 191.7 086 -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 18 235.6 152 +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 1994 Last Quarter J 05 F 03 M 04 A 03 M 02 J 01 J 30 J 30 A 29 S 28 O 27 N 26 D 25 New Moon J 11 F 10 M 12 A 11 M 10 J 09 J 08 A 07 S 05 O 05 N 03 D 02 First Quarter J 19 F 18 M 20 A 19 M 18 J 16 J 16 A 14 S 12 O 11 N 10 D 09 Full Moon J 27 F 26 M 27 A 25 M 25 J 23 J 22 A 21 S 19 O 19 N 18 D 18 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!