Last Updated:
2010 Jan 30 23:30 UTC
Source file:
forthcoming_meteors.txt
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Meteor Activity in 2010Edited by Tony MarkhamIn 2010, moonlight conditions will be favourable for the maxima of the Perseids, Taurids and Geminids. The Quadrantids, Lyrids, Eta Aquarids, Orionids and Leonids will suffer from significant moonlight interference, whilst the Delta Aquarids-S and Ursids peak close to Full Moon and thus will be severely affected.. Quadrantids max Jan 03d18h UTChart. The Quadrantid radiant, lying at Dec +50, is circumpolar for observers north of latitude 40 N. The radiant is at its lowest altitude at around 20h local time and is highest at the end of the night. The maximum is usually rather narrow, with the predicted time for 2010 favouring observers at Asian Longitudes. However it should be noted that the 2009 peak was broader than usual with the ZHR being above 100 for nearly 12 hours. The Moon will have been Full on Dec 31 and so will still be a problem from mid evening onwards by the night of maximum.VirginidsAfter the Quadrantids, night time meteor rates are rather low for northern hemisphere observers. However, from mid February to early May there are a number of minor showers, collectively referred to as the Virginids, whose radiants lie close to the ecliptic. Examples include the Delta Leonids (max Feb 26), the Alpha Virginids (max Apr 11-12) and the Gamma Virginids (max Apr 14). Peak rates generally occur in early April. New Moon in 2010 occurs on Feb 14, Mar 15 and Apr 14.Lyrids max Apr 22d16h UTChart. Lyrid activity can be seen from Apr 18-25 each year. For observers at northern latitudes, the Lyrid radiant is above the horizon all night. As for many of the major meteor showers, observed rates pick up as the radiant altitude increases during the night, so meteor watches after midnight are the most productive. The Lyrids are the main night time meteor shower of the spring months for northern hemisphere observers. Although they don't usually produce observed rates comparable with major showers that occur later in the year, the Lyrids do stand out relative to the low background activity of the spring months. Some intense but brief Lyrid outbursts have occasionally been seen, such as in 1982.With First Quarter occurring on Apr 21, observations of the maximum of the 2010 Lyrids will be hindered by moonlight, especially for observers at more northerly latitudes from which moonset will not occur until close to dawn. Observers less far north will however enjoy a moonless interval between moonset and dawn. Eta Aquarids max May 4This shower is active from late April to mid May and produces higher peak ZHR values than do the Lyrids. However, while easy to observe from the southern hemisphere and from the tropics, for observers in northern Europe dawn is approaching before the radiant reaches a reasonable altitude. Thus observers at northern latitudes can only expect to see low observed rates.In 2010, the Eta Aquarid peak occurs shortly before Last Quarter and so there will be some moonlight interfence by the time that the radiant rises on the night of maximum. The radiant is in northern Aquarius, at RA 22h20m, Dec -01. Daytime showersFor observers at northern latitudes the Eta Aquarids are almost a daytime-only shower. However, active throughout May and June are several showers whose radiants are only above the horizon during daylight hours (although in a few cases, some activity may be detectable late in the night by observers in tropical latitudes). Consequently observation of these showers is limited to radio methods. ZHR and radiant information is generally poorly known. The most active of these showers appear to be the May Arietids (max May 16), the Omicron Cetids (max May 20), the Arietids (max Jun 7), The Zeta Perseids (max Jun 9) and the Beta Taurids (max Jun 28).June Bootids max Jun 23-24?This shower produced an unexpected outburst in 1998, with a broad peak during June 27-28. Another outburst was seen on 2004 June 23. Although several outbursts from this shower were seen in the early 20th century, these latest outbursts were unexpected as the Earth now passes some distance from the orbit of the particles which produced the earlier outbursts. The parent comet 7P/Pons-Winnecke was at perihelion on 2008 Sep 26, but there is no evidence that recent outbursts have been related to the position of the comet. It is worthwhile monitoring this shower's activity however in case further outbursts occur. Indeed, there are suggestions that the Earth may encounter a dust trail during the night of 2010 Jun 23-24. There is some uncertainty as to the current location of the shower radiant, with recent reports merely describing the activity as originating from "northern Bootes".In 2010, Full Moon occurs on June 26. It is worth noting, however, that for observers at the more northerly latitudes, the Moon, when present, will be low in the sky and so any negative influence on sky darkness will be reduced (although all-night twilight may well be a problem!) July Minor ShowersNight-time sporadic activity picks up in July. Among the minor showers sometimes listed are the Alpha Cygnids, which are active throughout the month and into early August (radiant 21h00m, +48) and the Lacertids, which are active later in the month (radiant 22h05m, +37). Neither shower seems to have any clearly defined maxima. New Moon in 2010 occurs on July 11, with Full Moon occurring on July 26.Aquarid/Capricornid complexChart. This group of showers includes the Delta Aquarids-S (max July 28-29), the Piscis Australids (max July 31), the Alpha Capricornids (max Aug 2), the Delta Aquarids-N (max Aug 5-9) and the Iota Aquarids-S (max Aug 6-7). Other than for the Delta Aquarids-S, the peak ZHRs are all below 10 per hour. The proximity of the radiants to each other, together with their motion from night to night means that visual observers must take great care to distinguish between the individual showers. The Alpha Capricornids have been noted for producing a number of slow moving flaring fireballs. Rather confusingly some sources refer to the Alpha Capricornids as the Capricornids, whilst others use the term Capricornids to describe a minor shower peaking around July 25 !With Full Moon in 2010 occurring on July 26 and Last Quarter on Aug 3, the first three of these showers are rather unfavourably timed, but the other two showers will be less seriously affected. Perseids max Aug 12d21h UTChart. Despite not producing peak rates as high as those of the Geminids, the Perseid meteor shower remains the favourite for most observers. This is because, in addition to being rich in bright and trained meteors, it also occurs during summer in the northern hemisphere as opposed to the cold nights of December for the Geminids. Perseid activity can be seen from the last week of July through to the third week of August. The highest observed rates on any given night are likely to be seen when the radiant is highest in the sky late in the night. The more detailed analyses of recent decades have also shown that there is often more than one Perseid peak, the supplementary peaks being shifted several hours away from the main peak and probably associated with dust trails left behind by specific perihelion passages of the parent comet.Moonlight conditions in 2010 will be mostly favourable. Observations of the early Perseids will be adversely affected by the Full Moon of July 26, but after Last Quarter (Aug 3), moonlight will be much less of a problem. New Moon occurs on Aug 10. August Minor ShowersSporadic activity is quite high in August and numerous minor showers have been reported as being active. Many of them are probably spurious, with some of their supposed members being misidentified Perseids and late members of the Aquarid/Capricornid complex.The more reliable showers include the Alpha Aurigids, which reach maximum late in the month (radiant RA 04h56m , Dec +43), and the Kappa Cygnids which reach maximum on Aug 20 (radiant 19h20m, +55) and often produce fireballs. Some sources also list an Iota Aquarid-N maximum on Aug 20 and a second Kappa Cygnid maximum on Aug 26. New Moon in 2010 occurs on Aug 10, with Full Moon occurring on Aug 24. Minor Showers in SeptemberSporadic activity is also high in September and, again, numerous minor showers have been reported - although not as many as for August, probably because less observers are usually active. The more reliable minor showers include the Alpha Aurigids (continuing from August), the Beta Cassiopeids (max Sep 1-6, radiant 00h05m, +63), the Epsilon Perseids (max Sep 3-7, radiant 04h10m, +37), the Delta Aurigids (max Sep 8, radiant 04h00h, Dec +47) and the Piscids (max Sep 8-9, radiant 00h36m, +07 ; max Sep 21, radiant 00h24m, +00). New Moon in 2010 occurs on Sep 8, with Full Moon occurring on Sep 23.October Camelopardalids max Oct 5-6 ?In 2005 and 2006, enhanced meteor activity from Camelopardus was recorded on video around this date. On neither occasion were there visual records of high activity, although the bright nearly Full Moon would have made observation very difficult in 2006. If this is an annual shower and it occurs at the same solar longitude each year, then it might be seen again around 01h-03h30m UT on 2010 Oct 6. This would favour observers at European longitudes, but it would be also be worthwhile observers at other longitudes monitoring for activity given the vagueness of the details reported to date. Moonlight circumstances will be favourable in 2010, with New Moon occurring on Oct 7.Giacobinids (Draconids) max Oct 8-921P/Giacobini-Zinner, the parent comet of this shower, passed through perihelion in July 2005, with some enhanced activity been reported when the Earth passed close to the comet's orbit at around 17h UT on Oct 8 2005. With the comet still being some way from perihelion, little or no activity is likely to be seen in 2010. The radiant, at RA 17h23m, Dec +57, lies near the head of Draco.Orionids Max Oct 20-23Chart. Orionid activity lasts from Oct 14-31, with a broad maximum occurring between Oct 20 and Oct 23 - however, even within this period there will be several peaks and troughs in the activity levels. The Orionids sometimes brings surprises such as the unusually high rates seen during the night of 2006 Oct 21-22. There were also indications of enhanced rates in 2008 and 2009The radiant position at maximum is RA 06h24m , Dec +15 (on the border of Gemini and Orion) but actually appears quite diffuse since it consists of a number of sub-centres, as shown by the chart, whose combined activity can give the impression of the radiant remaining almost stationary for several days. The Orionid radiant does not rise until mid evening and is highest in the sky late in the night. In 2010, First Quarter occurs on Oct 14 and Full Moon occurs on Oct 23, so the best times for observing are likely to be after moonset late in the nights of Oct 18-19 to Oct 21-22. Taurids Max Nov 7Chart. Activity lasts throughout October and November, with a broad maximum in early November. Observed rates are far from spectacular, but some observers report that the shower produces a good percentage of fireballs. Indeed a good number of bright Taurids were reported in 2005. Some Taurid activity will also be visible during the Orionid watches of October and the Leonid watches of November. The Taurid radiants are highest at around the middle of the night.The 2010 maximum is favourably timed, with New Moon occurring on Nov 6. Leonids max Nov 18dChart. Leonid activity last from Nov 14-20 each year. The Leonid radiant rises in the late evening and is highest in the sky around dawn. The Leonids produced storm level activity for observers at favoured locations in 1999, 2001 and 2002. It had been assumed that we had encountered all of the significant Leonid filaments. However, in 2008 the Earth passed close to a filament of material ejected at the 1466 return of the parent comet, resulting in rates being enhanced to around normal Perseid levels. A further close approach to this filament in 2009 resulted in similar rates during 20h-21h UT on Nov 17. Observing conditions will be fairly unfavourable in 2010 with First Quarter occurring on Nov 13 and Full Moon on Nov 21, restricting dark skies near maximum to a few hours late in the night. Geminids max Dec 14d06h UTChart. Although the Geminids were overshadowed by the enhanced Perseid activity of the early 1990s and the enhanced Leonid activity of 1998-2002, the Geminids are the shower that produce the highest reliable rates year on year and only lose out in popularity to the Perseids due to the colder December nights. Geminid activity can be seen from Dec 7-16. Results from recent years have shown the peak ZHR to be over 100 and to remain above 70 per hour for about 24 hours - and the shower's profile is evolving from year to year. The Geminids are typically rich in bright meteors, but produce few trained meteors. The radiant is highest at about 02h local time and for observers at northern temperate latitudes is above the horizon all night.Moonlight conditions are fairly favourable for the Geminids in 2010 with New Moon occurring on Dec 6 and First Quarter occurring on Dec 13, meaning that moonset at Geminid maximum will occur soon after midnight. Ursids max Dec 22-23Ursid activity lasts from approx Dec 17-25, with the radiant, at RA 14h28m, Dec +78, being highest late in the night and circumpolar for most northern hemisphere observers. High rates were recorded from this shower in 1945, 1982 ,1986, 2000, 2004 and 2006. It is suspected that other such peaks may have been missed due to lack of observations. With Full Moon occurring on Dec 21, Ursid observations in 2010 will be seriously hindered by moonlight.Quadrantids 2011 max Jan 04d00h UTChart. The Quadrantid radiant, lying at Dec +50, is circumpolar for observers north of latitude 40 N. The radiant is at its lowest altitude at around 20h local time and is highest at the end of the night. The maximum is usually rather narrow, with the predicted time for 2011 favouring observers at west Asian and east European longitudes. However it should be noted that the 2009 peak was broader than usual with the ZHR being above 100 for nearly 12 hours. The 2011 peak occurs close to New Moon, so moonlight will not hinder observations.#include "style/footer.h" |
