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met12.qxd 17/06/2011 15:43 Page 68

68 Astronomical Calendar 2012 Arc tur AltairAltair uuss 360360˚ eclipticecliptic 3453 4 5 ˚ llongitudeongitude 330330˚ 315315˚ 330000˚ 228585˚ 270270˚ 255255˚ 240240˚ 222525˚ 221010˚ 195195˚ 180180˚ + ++252r5e˚ + 2 o++2525˚ qua 1 0 o 0 at S Gre e q ++2020˚ M u a +20+20˚ s A OPHIUCHUSOPH t o su UIL i IUCH r ega AQUILAAQ US of P o r l ++1515˚ a t k ++1515˚ u S y e q RIU A AlphaAlpha CCapricornidsapricornids QU W ++1010˚ EtaEta AquaridsAquarids AQUARIUSA JulJul 2299 ++1010˚ MayMay 5 a y VIRGOVIR e ES GO d + 5˚ SC S + 5˚ u I TTARIU LIBRAL t PISCESP SAGITTARIUSAGI IB i RA t

a l AntihelionAntihelion AntihelionAntihelion e c l i p t i c 0˚ AntihelionAntihelion 0˚ c AugAug 1155 AugAug 1 AntihelionAntihelion i AntihelionAntihelion JulJul 1155 AntihelionAntihelion AntihelionAntihelion AntihelionAntihelion AntihelionAntihelion AntihelionAntihelion t AntihelionAntihelion JulJul 1 JunJun 1155 JunJun 1 SpicaSp AntihelionAntihelion p SepSep 1 MayMay 1515 MayMay 1 AprApr 1155 AprApr i1 i AntareAn c MarMar 1515 l --55˚ US tares a --55˚ c RN ecliptic latitude e ICO DeltaDelta AquaridsAquarids APR CAPRICORNUSC SCORPIUSSCO --1010˚ JulJul 2299 RPIUS --1010˚

--1515˚ --1515˚ LUPUSLU ut PUS alha -20-20˚ FomalhauFom --2020˚ o h h o h h 0 2 h h 1 h 3 3 2 0 0 h h h 5 1 1 2 4 1 2 1 9 1 8 1 7 1 6 4 h 3 h 1 h -25-25˚ 0 - - 2 2 --2525˚ CoordinatesCoordina tes ooff 22012012 Meteor Glossary r-values: r is the , computed from the METEORS by Alastair McBeath Atmospheric velocity: The meteors’ apparent speed as shower’s magnitude distribution. It gives an accurate mea- The “big three” major annual showers, the , seen from the Earth’s surface. This is primarily determined sure of the proportions of bright and faint meteors expect- and , each have some moonless skies in by the direction of each meteor’s approach, and ranges ed from the shower. r = 2.0-2.5 indicates meteors that are prospect for their maxima in 2012, of which the Geminids from 11 km/sec (very slow) for objects moving in the same generally brighter than average. If r = 3.0 or higher, more are the most favourable, with a peak at new Moon. Earlier, direction as the Earth, up to 72 km/sec (very fast) for mete- faint meteors can be expected. r for sporadic meteors is nor- the also benefit from new Moon in April, while the ors arriving head-on. Even very slow meteors move across mally around 2.9-3.1. latest Taurid “swarm” return, expected around late October the sky far faster than the swiftest artificial satellites, which Shower : The area of sky that specific shower to mid , could produce a particularly fine crop of they otherwise resemble to a visual observer. meteors seem to emanate from, if their paths are projected bright to fireball-class meteors. Bolide: A very bright fireball-class meteor. Some author- back in straight, imaginary, lines from where they appeared. ities regard only sound-producing meteors as bolides The constellation or bright star nearest to this area at the Welcome to the new-look Astronomical Calendar Meteors (whether the noises are heard some time after the meteor, shower’s maximum names the shower. column! Regardless of our own views on the subject, change due to acoustic waves, or simultaneous with its occurrence, Solar longitude: A very accurate means of measuring is a natural part of life. With meteor astronomy, since the a result of exceptionally rarely detected Very Low the Earth’s position in its annual orbit around the Sun, based International Meteor Organization (IMO) was formed in the Frequency radio waves), while others class the lower bound- on the Sun’s apparent position on the ecliptic, measured in late 1980s, we have seen many changes. Thanks to a huge ary as being magnitude —9. From the Greek bolis, “missile.” degrees. Solar longitude 0° is at the northern spring amount of fresh data collected and analyzed using a single The term “superbolide” has recently been coined for satel- equinox, 90° at the northern summer solstice, and so forth. visual observing method since then, parame- lite-detected fireballs of magnitude —17 or brighter. The apparent motion of the Sun varies slightly during the ters that had remained largely unchanged for decades were Fireball: An especially brilliant meteor, which by inter- year, but averages roughly 1° per day. 0.1° of solar longitude discovered to have inaccuracies, and our supposed level of nationally-agreed definition must be at least magnitude —3 is thus about 2.4h. understanding, even of how some of the major sources might or brighter. Sporadic meteors: Randomly distributed meteors that behave, had to be reviewed. The past dozen years have Meteors: Streaks of light in the night sky produced are visible at any time of night throughout the year. They are brought an influx of new instrumental results for many show- when tiny dust particles enter the Earth’s upper atmosphere normally more abundant between local midnight and dawn, ers, thanks to automated imaging techniques. Suddenly, we and ablate by friction due to their high velocities. and during the second half of the year for northern hemi- have discovered an entire raft of showers too weak to be Sometimes called shooting or falling stars. From the Greek sphere observers. defined visually, which automated video equipment, operat- meteoros, “things raised up in the air,” the same root as ZHR: , the maximum number of ing tirelessly night after night, has identified. Visual meteor “meteorology.” meteors an excellent observer could see from a shower if its plotting, for so long a key element in trying to identify mete- Persistent trains: Glowing ionized gas left along the radiant were directly overhead and the sky perfectly clear ors from the minor showers, while not quite redundant, has paths of mainly the faster and brighter meteors. Visible only (magnitude +6.5 stars visible). Haze, clouds and bright no strong value in studies of such low-activity sources now. after the meteors themselves have disappeared, they nor- moonlight drastically reduce the observed number of mete- However, visual meteor observing is far from redundant! mally last for a few seconds at most. Much rarer examples ors, since fainter meteors become effectively invisible. Low One essential aspect that automated video observing cannot last for minutes or more, often twisting into an “S”-shape radiants, or times away from the shower’s peak, also pro- resolve properly is how meteor showers behave over time, before completely fading, due to high-atmosphere winds. duce many fewer meteors. especially when defining their maximum activity. This is best achieved visually for those showers whose highest ZHR is at least 5 or 6. Since most meteor observers continue to prefer slightly eccentric active dates. Its likely ZHRs are typically 14 or so. Unfortunately, the last really high return was with- the visual method, and most reading the Astronomical around two or three, but may reach three to four in early out the examined database, in 1982, when American Calendar watch from the mid-northern hemisphere, the April, late April to early May, late May to early June, and late observers briefly recorded a ZHR of 90, so giving no clues as sources discussed here have been reduced significantly in June to the opening days of July. to when another such outburst might happen (hence the number this year, to concentrate on those likely to produce Wed 4 Jan, 07h UT. Quadrantids. Active Dec 28-Jan 12. shower is always one to watch). The radiant, on the Lyra- ZHRs of this amount or more, whose radiants are visible in ZHR 120 (variable 60-200). Atmospheric velocity 41 km/sec. Hercules border at maximum, is usefully on view after about the night sky from such locations. Similarly, the observing cir- r 2.1 (variable). Waxing gibbous moonset near the 22h30m local time, improving in elevation all night. April’s cumstances describe the situation chiefly for the mid-north- Quadrantid maximum provides a few pre-dawn hours to New Moon on the 21st makes this a perfect year for ern hemisphere as well. Of course, the more southerly show- watch for the shower, quite favourable, as while its radiant is observers, and the ideal peak time would favour places in ers and lesser sources once discussed here, and many others, circumpolar from many sites, it reaches a useful elevation North America, particularly the eastern half. Lyrids are swift together with the daytime showers available to radar and only after 23h, to be highest in the sky near dawn. It lies in meteors, occasionally spectacularly bright, with approximate- radio detectors, still exist, and for those interested in follow- northern Boötes, an area once filled by an 18th-19th century ly 20-25% leaving persistent trains. ing them, we advise observers to refer to the IMO’s annual constellation, Quadrans Muralis, the Mural—Wall— SAT 5 May. Eta Aquarids. Active Apr 19-May 28. Mean Meteor Shower Calendar for the current year, available online Quadrant. It had been suggested the peak could happen ZHR 60 (periodically variable, ~40-85). Atmospheric velocity at www.imo.net. sometime between roughly 01h to 10h UT on January 4 in 66 km/sec. r 2.4. This shower’s radiant, in the little “Y”- As for many years, the information below is based on that 2012, rather than at the specific time noted above, and might shaped “Water Jar” asterism of Aquarius, rises in twilight only Shower Calendar’s, which is as accurate and up-to-date as have two more active phases, within an hour of 02h and 08h an hour or two before dawn at mid-northern latitudes. possible, based on the more reliable data and analyses. Most UT (the second probably the stronger, if so). However, a Observers nearer, and south of, the equator have enjoyed of the showers are given in order of their dates of maximum. more recent re-evaluation of that model has indicated this to more success for it, with 2+ hours of twilight-free sky after Predicting such maxima is not an exact science, and most are be less likely. Previous investigations have found the radiant-rise for sites at 35° south, for example. It is one of two estimated using previous years’ results or theoretical models. Quadrantid ZHR may vary from year to year, and that its max- showers associated with 1P/Halley, last at perihelion Past observations are usually a good guide to the day or half- imum timing may not be constant. The 07h time is based on in 1986. The other is the in October, and like the day, but at shorter timescales, there may be problems. solar longitude 283.16°, close to when the main Quadrantid Orionids, Eta Aquarids are very swift, bright and frequently Similarly, although theoretical predictions are frequently peak has repeated in most years since 1992. Radio-visual (40-60%) leave persistent trains. Both showers also show a given with to-the-minute precision, uncertainties in the mod- observations since 2000 have suggested a possible double number of submaxima around their main peak, although the els mean these should be treated as guides only, not absolute maximum on occasion, the second potential peak some 9-12 Eta Aquarid maximum is generally the strongest from either. expectations. Consequently, it is best to keep watch for as hours after the visual one. Mass-sorting of meteor particles An analysis of IMO data suggested both sources were vari- much of the night as possible when a shower maximum is within the shower may further cloud the issue, so very faint able in their peak rates, reaching their higher maxima togeth- due. In addition, many showers produce meteors for days or meteors perhaps peak up to 14 hours before the visual ones. er, roughly every twelve years (if so, a periodicity probably weeks to either side of this peak date, so observations of a The 07h timing would fall best for sites in North America and governed by Jupiter’s 12-year orbit). Rates should be falling shower often can continue on other nights. You must know on the North Atlantic Ocean, with the longer interval extend- now towards the next trough around 2014-16, if this cyclici- where the active shower radiants will be for any dates you are ing this favoured zone east as far as western Asia (if the max- ty is correct. Eta Aquarid ZHRs are often above 30 between observing on, to identify meteors from those showers. To imum happens earlier) or west (later). Activity more than a May 3-10 regardless of this. Unfortunately, full Moon on May help in this, the shower radiants discussed here are illustrated day or two from the peak tends to be low, so is liable to be 6 creates about the worst viewing conditions for the peak. either among the monthly notes, or on the near-ecliptic dia- detected solely instrumentally other than during the opening Wed 27 Jun. June Boötids. Active June 22-Jul 2. ZHR vari- gram accompanying this column. Good luck, and clear skies week of January. able, 0-100+. Atmospheric velocity 18 km/sec. r 2.2. A strong for all your observing! SUN 22 Apr, 05h UT. Lyrids. Active Apr 16-25. ZHR vari- (ZHRs 50-100) June Boötid return in 1998 was completely Antihelion Source. Active Dec 10-Sep 10. ZHR up to 4. able, may be up to 90, generally averaging 18. Atmospheric unexpected, as the shower had been dormant for 70 years. It Atmospheric velocity 30 km/sec. r 3.0. Antihelion meteors velocity 49 km/sec. r 2.1. An analysis of IMO Lyrid data from probably resulted from material shed in the 19th century by emanate from a large, roughly oval, area approximately 30° in 1988-2000 found the maximum might fall between solar lon- the shower’s parent comet, 7P/Pons-Winnecke, along with a Right Ascension (two hours) by 15° in Declination, centred gitudes 32.0°-32.45° (2012 April 21, 21h to April 22, 08h similar outburst, yielding ZHRs of 20-50, on 2004 June 23. on its radiant location for any given date. This area culminates UT), with an ideal at 32.32°, as above, typically producing Three other returns are suspected, from 1916, 1921 (very daily at about 01h local time. It is considered present all year somewhat higher rates, ZHRs around 23. The further the uncertainly recorded) and 1927, all years near Pons- except when the Taurid showers are underway, hence its peak fell from this ideal, the lower the rates—ZHRs down to Winnecke’s perihelion, unlike more recently. Currently, the met12.qxd 17/06/2011 15:43 Page 69

Astronomical Calendar 2012 69

118080˚ eclipticecliptic 1651 6 5 ˚ llongitudeongitude 150150˚ 135135˚ 120120˚ 105105˚ 9900˚ 7755˚ 6600˚ 4455˚ 3300˚ 1155˚ 0˚ +25+25˚ ++2525˚ + 4 o apella + + 3 0 CapellaC 2 0 o 0 o ++2020˚ A +20+20˚ AlphaAlpha AAurigidsurigids AURIGAAURIG y US AugAug 3311 a ERSE W PERSEUSP +15+15˚ GeminidsGeminids ++1515˚ DecDec 1313 y + 1 CastorCasto k ++1010˚ 0 o LEOLE r l ++1010˚ O PolluxPollu i LeonidsLeonids x S e NovNov 1717 M es RIE ES d + 5˚ eiad ARIESA ISCESC + 5˚ u Pleiadesl PISP t 1 h ReR i 2 eggulus GEMINIEM t ulu INI a s l e c l i p t i c e c l i p t i c 0˚ NorthernNorthern TTauridsaurids 0˚ c i NovNov 1212 t AntihelionAntihelion AntihelionAntihelion AntihelionAntihelion p AntihelionAntihelion AntihelionAntihelion DecDec 1515 i AntihelionAntihelion JanJan 1 l MarMar 1 --55˚ FebFeb 1155 FebFeb 1 -5-5˚ c JanJan 1515 CANCC n SouthernSouthern TTauridsaurids r ecliptic latitude e AN AldebaranAldebara OctOct 1010 t o CEERR u a CANISC OrionidsOrionids e q -10-10˚ - 1 e ANIS OctOct 2211 --1010˚ 0 o q u US a t MINORM TAURUTAUR o r INOR US --1515˚ BetelgeuseBetelgeuse CETUSCET --1515˚ ProcyonProcyon

--2020˚ 1 1 h --2020˚ - AlphaAlpha MMonocerotidsonocerotids ORIONORION 2 o NovNov 2121 h h 0 h h h h h h 1 0 h 9 h 8 7 6 5 3 2 1 -25-25˚ 4 --2525˚ CoordinatesCoordinates ooff 22012012 Most shower radiants mentioned are shown in this ecliptic- comet’s orbit lies about 0.24 astronomical units outside the 22h-23h local time. The waning Moon, a day past last quar- based map, and/or the monthly sky maps; except the l Earth’s, so a direct influence on shower activity is unlikely. ter on the 9th, rises at about this time for mid-northernRige watch- Perseids (see August page) and Epsilon Eridanids (see text). The comet was last at perihelion in September 2008. ers, so will leave at best just a fairly brief dark-sky window to Hatched tracks show the eastward radiant drifts during Predictions of activity possibly similar to the 2004 event were check on it. The repeat time for the 2008 outburst in 2012 is their activity. made for 2010 June 23 and 24, but largely failed to materi- roughly betweenSiri u08h30m-09h30ms UT. alise. Even allowing for the bright Moon then, ZHRs were Wed 12 Sep. Epsilon Eridanids. Active Sep 9-12? ZHR 0- indicates there should be a repeating pattern in such “swarm” below 10, and some observers failed to see any potential 40? Radiant 03h48m —12°? Radiant drift, atmospheric veloc- returns every 61 years. The 1951 Taurid return was so prolif- shower meteors at all. The repeat time for the 1998 peak ity and r, all unknown. Virtually nothing is certain about this ic in these brighter meteors between October 28 and would be within six hours of 03h UT on June 27, while IMO possible occasional shower. It has been linked to Comet November 11, it was one of the key pieces of evidence which video data found very weak annual rates primarily at solar C/1854 L1 Klinkerfues, and suggestions are a dust trail from helped formulate the Taurid “swarm” theory in the first place! longitude 92°, 2012 June 23. Late June’s waxing Moon (first the comet might produce ZHRs of about 10 near 13h09m Disappointingly, full Moon falls on October 29, so there will quarter is on June 27) is favourable for further investigations UT on September 12. If the position is accurate, the radiant be problems for normal visual meteor watching during the this year, with the radiant area readily on view nearly all night can be observed from mid northern sites only after 02h (it early part of the likely “swarm” event, gradually lessening dur- in northern Boötes (its precise location is somewhat uncer- rises around local midnight). It is better-viewed from the ing early November, till new Moon graces the Northern tain). Unmistakably slow meteors. southern hemisphere. Nearly-new Moon should allow cover- Taurid peak. However, if the meteors are as bright as hoped, SUN 29 Jul. Delta Aquarids. Active Jul 12-Aug 23. ZHR age of whatever happens, and if correct, the peak time would even the Moon may not conceal too much. Remember 16. Atmospheric velocity 41 km/sec. r 3.2. If not for the wax- favour locations across the central-eastern Pacific Ocean. If though that nothing in meteor astronomy is certain! ing gibbous Moon in 2012, this shower’s relative peak anything of the shower was observed at the proposed 2011 SAT 17 Nov. . Active Nov 6-30. ZHR 15? strength should allow it still to be comfortably separated from return (still to come when I wrote this), the shower parame- Atmospheric velocity 71 km/sec. r 2.5. Though their parent the nearby large Antihelion radiant, primarily from more ters may be refined ahead of the potential 2012 event. comet 55P/Tempel-Tuttle’s latest perihelion passage was in southerly sites. The general area of sky is available for useful Mon 8 Oct. . Active Oct 6-10. ZHR variable, 0- 1998, the Leonids have continued to produce variable activi- observing virtually all night. Recent analyses suggest the max- storm. Atmospheric velocity 20 km/sec. r 2.6. Strong ty since their last near-millennial storm in 2002. This time, no imum may not be so sharp as the single date here implies, Draconid showers sometimes occur near their parent comet, strongly enhanced activity is forecast, but there could be and rates may be similar from July 28-30. Expect chiefly faint, 21P/Giacobini-Zinner’s, perihelion passages, such as in 1998, more than one maximum, based on theoretical models. medium-speed meteors, with occasional significantly brighter when a short-lived outburst with ZHRs of ~700 happened. These comprise: Nov 17, 09h30m UT (nodal-crossing time, events. Around 5-10% leave persistent trains. The most recent storm was in 1946. In 1999 an unpredicted ZHRs about 15?); Nov 17, 21h (ZHRs maybe 5-10?); and SUN 29 Jul. . Active Jul 3-Aug 15. minor outburst took place (ZHRs ~20 briefly), while the 2005 Nov 20, 06h (the 1400 AD dust-trail, ZHRs circa 10-15, but ZHR 5. Atmospheric velocity 23 km/sec. r 2.5. Typical Alpha perihelion return produced a largely unexpected short-lived probably below-average-brightness meteors). In all cases, the Capricornids are slow and bright (sometimes of fireball class), event with visual ZHRs of ~35, but radar rates equivalent to waxing Moon presents no problems for observers, setting very photogenic, despite their low rates. A minor enhance- a ZHR of ~150. The 2011 predictions were still to be fulfilled before the Leonid radiant is properly on view, after 23h-00h ment in ZHRs to ~10 was observed from Europe in 1995, when this was written, though nothing unusual is expected local time for most sites. Leonids approach the Earth nearly though the usual highest rate is nearer 5, probably happening for 2012. Repeat timings for the recent outbursts would span head-on, so are extremely swift, often bright, and 50-70% around July 29-30 this time. The radiant, accessible all night, the interval from 03h-20h UT on the 8th. Good news is last leave persistent trains. overlaps the Antihelion area, necessitating great care to sep- quarter Moon then rises only in the very late evening for mid- Wed 21 Nov, 10h UT. Alpha . Active Nov arate the two. As with the Delta Aquarids, the approaching northern sites, from most of which the radiant is circumpolar, 15-25. ZHR variable 3-400+. Atmospheric velocity 65 first of August’s two full Moons makes this a poor year for highest in the early evening. Draconids are extremely slow- km/sec. r 2.4. This usually minor shower’s most recent out- Alpha Capricornid viewing. moving. burst in 1995 gave an estimated peak ZHR, lasting about five SUN 12 Aug. Perseids. Active Jul 17-Aug 24. ZHR 100. Wed 10 Oct. Southern . Active Sep 10-Nov 20. minutes, of ~420. The whole outburst lasted 30 minutes, cen- Atmospheric velocity 59 km/sec. r 2.2. The Perseids showed ZHR 5. Atmospheric velocity 27 km/sec. r 2.3. The Taurids tred on solar longitude 235.27°. Such a well-observed event a multiple (typically double) peak with enhanced rates, from dominate the Antihelion activity throughout most of the transformed our knowledge of the shower, but uncertainties 1991-98, and again in 2004, when ZHRs were ~200+ briefly. northern autumn, and like that Source, both Southern and, about its future activity remain, and the next strong outburst In between, and since, activity has been more “normal,” with when active, Northern Taurid (see below) radiants are large may not be till 2043. The radiant is some degrees south-east a single maximum scheduled to repeat in 2012 probably oval areas, roughly 1h20m in Right Ascension by 10° in of Procyon (a Canis Minoris), so it can be observed after between 07h to 19h30m UT on August 12, most likely near- Declination, centred on the location for any given date. Both about 23h local time. First quarter Moon on November 20 er the nodal crossing around 12h-14h30m. No stronger activ- remain well above the horizon all night, and the showers are favours coverage of the peak under near-ideal conditions, as ity at other times was expected when this was written, but associated with Comet 2P/Encke. Fresh IMO evidence sug- it will set between midnight and one a.m. on the 21st. that is not a guarantee! The Perseid radiant reaches a suitable gests the Southern branch, rather than reaching its maximum Thu 13 Dec, 07h to Fri 14, 04h UT. Geminids. Active elevation by 22h-23h local time from mid-northern sites, in early November as long believed, actually has its peak in Dec 4-17. ZHR 120 (slightly variable). Atmospheric velocity improving thereafter. The waning crescent Moon rises half an October instead. A waning crescent Moon gives ample 35 km/sec. r 2.6. New Moon falls perfectly for this splendid hour or so either side of local midnight on the 12th, but opportunity to check on that this year. shower’s peak, one of the very best presently visible from despite its relative brightness and proximity to the Perseid SUN 21 Oct. Orionids. Active Oct 2-Nov 7. Mean ZHR Earth. The Geminid radiant at maximum is just north of radiant, it will likely prove more of a nuisance than a real 23 (periodically variable, ~15-30). Atmospheric velocity 66 Castor (a Geminorum), available for observing almost all deterrent for watchers. The nodal peak timing would favour km/sec. r 2.5. Associated with Comet 1P/Halley, like their night after the early evening. It culminates around 02h. locations from eastern Asia east across the North Pacific twin of May the Eta Aquarids, but the Orionids’ overnight Geminid near-peak activity is very persistent. ZHRs of around Ocean to far western North America, if correct. Perseids are accessibility means they have been better examined. Video 80-130 are often seen for almost a day, as indicated above. fast, often bright, and frequently leave persistent trains. results have found a single, simple radiant, rather than the Geminids are also typically bright, medium-speed meteors, Fri 31 Aug. Alpha . Active Aug 25-Sep 10. ZHR more complex one earlier suggested by visual plotting data. though few leave persistent trains. Fainter telescopic 6. Atmospheric velocity 66 km/sec. r 2.6. As discussed in the Several maxima apart from the main one may occur, if not Geminids are most numerous roughly a day before the visu- last two Astronomical Calendars, the near-Auriga showers especially predictably. One notable event, comparable in al ones, possibly from a triple radiant. The shower is unique active from late August to mid October have recently been strength to the chief maximum, occasionally happens around in its association with an Apollo asteroid, 3200 Phaethon. intensively investigated using IMO visual and video data. October 17-18 (most recently in 1993 and 1998), while a SAT 22 Dec. . Active Dec 17-26. ZHR occasional- Some further minor refinements are likely to this source’s couple of nights over the main peak produced sometimes ly variable, up to 50+, normally 10. Atmospheric velocity 33 parameters, though the radiant’s location does seem to be in unexpectedly strong ZHRs of ~40-70 in 2006-2009. No km/sec. r 3.0. This shower’s north-circumpolar radiant, near central-eastern Auriga, not nearly so close to Capella (a enhanced activity is expected this time, though October’s Kochab b Ursae Minoris), rises to be highest towards dawn, Aurigae) as was long thought. This means the shower is now waxing crescent Moon on the 21st means perfect observing so although the waxing gibbous Moon does not set until observable chiefly after 01h local time. Brief, occasional out- conditions for the maximum. The Moon will be setting by the roughly two a.m. on the 22nd, this return is not wholly bursts came from it in 1935, 1986 and 1994 (ZHRs ~30-40), time the radiant has first reached an observable elevation, unfavourable. Several enhancements to ZHRs of 30 or so with the first predicted outburst in 2007 (ZHRs ~130 with after about 22h-23h local time. Typical shower meteors are have occurred recently, in 2000 and from 2006 to 2008, many bright meteors). Nothing comparable is anticipated this very fast, sometimes bright, and often (50%+) leave persistent while others may have been missed, as the increased activity time, just as well, as August’s second full Moon on the 31st trains. has commonly lasted only a few hours. The usual maximum ruins the maximum night for meteor watching. Mon 12 Nov. Northern Taurids. Active Oct 20-Dec 10. is likely to fall near 08h UT on December 22, but model cal- SUN 9 Sep. September Epsilon Perseids. Active Sep 5- ZHR 5. Atmospheric velocity 29 km/sec. r 2.3. A return of culations by French meteoricist Jérémie Vaubaillon have sug- 21. ZHR 5. Atmospheric velocity 64 km/sec. r 3.0. Previously the “swarm” of larger Taurid dust particles is predicted to gested the 2012 peak may happen near 03h UT on little-known, this shower sprang into the news after an unex- happen, probably around late October to mid November, December 22 instead. ZHRs will be likely 10-15 at either pected outburst of bright meteors happened from it on 2008 this year. The last four such events, in 1995, 1998, 2005 and time. Other peaks are not impossible! The shower’s parent September 9, caught primarily by video systems in North 2008, all brought enhanced Taurid rates and sometimes plen- comet, 8P/Tuttle, last reached perihelion in January 2008, America. Confirmed as an annual minor shower by the latest ty of fireballs. There seems a good chance 2012 could pro- and its proximity has been implicated in the outbursts of IMO video results, its radiant rises to a useful elevation by vide another event rich in brighter Taurids, because theory 2006-2008. Ursids tend to be faint and of medium-speed.