Meteor Shower Details

Quadrantids: Named after the disused constellation Quadrans Muralis, the Wall Quadrant, now amalgamated into northern Boötes. The peak lasts only a few hours, so can be easily missed, and the radiant, though circumpolar from Britain, is very low in the evening hours, and highest towards dawn. The peak is due around 19h UT on 2010 January 3, but theoretical considerations suggest a quite strong peak may fall earlier on that date, perhaps between ~12h to 16h UT. The Moon is unhelpfully waning gibbous on January 3. Peak ZHRs are occasionally variable (recent highs were 180 in 1992 and 160 in 2008), and a second, lesser, maximum has been found sometimes since 2000, mainly in radio observations about 9-12 hours after the main peak. Recent video reports have suggested very weak activity may continue till January 10, but visual observers have often struggled to see anything of them even by January 5 in the past. Medium-speed meteors.

Lyrids: Rates are normally ~15-20, but short-lived, more active bursts are sometimes recorded, most recently in 1982 (when ZHRs were ~90). The maximum time can vary. It is expected between roughly 03h to 14h UT on 2008 April 22, too late for overnight observing from Britain, but with a nearly-new Moon. The radiant is on the Hercules-Lyra border at the peak, not so near Vega as some people expect. It rises throughout the night from about 22:30 UT onwards. Medium-speed to swift meteors. The probable parent body is Comet Thatcher of 1861 (whose orbital period about 415 years).

η Aquarids: This shower is never easy to see from the UK, as the radiant rises shortly before dawn, about 01:30 UT, but occasional members have been spotted by British watchers. Activity is marginally easier to note from these latitudes after the peak, when the radiant rises a little earlier. An excellent shower in pre-dawn dark skies from the southern hemisphere though, and their rates, which may be variable, could be at their cyclical highest in 2010 (variable ZHRs from ~40-85). Rates often remain good for several days across the maximum from such places. Very swift meteors, often with long paths because of their low radiant, and fine persistent trains. The stream was laid down by Comet 1P/Halley, along with their autumn twin the Orionids. Halley was last at perihelion in 1986 (period around 76 years). The waxing gibbous Moon sets in time to allow dark-sky coverage from the southern hemisphere only.

June Boötids: An unpredictable source, the June Boötids produced an unexpected outburst in 1998, when ZHRs of 50-100+ were observed for over 12 hours, but rates were seen on just one date. Before this, only three returns of the shower were known, in 1916, 1921 and 1927. Another ZHR ~50 outburst happened on 2004 June 23. The shower is associated with Comet 7P/Pons-Winnecke, last at perihelion on 2008 September 26. The waxing crescent Moon presents no problems when checking for any activity near its potential maximum this year, but the short, twilight nights are unhelpful for British watchers. However, even casual observers here spotted the activity in 1998. Very slow meteors.

δ Aquarids: Although the summer ANT radiant is uncomfortably nearby to their north, this shower is strong enough to stand out as distinct from the ANT meteors. It is not seen at its best from the UK though, thanks to its southerly radiant. Great care must be taken to separate δ Aquarids from ANT and CAP meteors in July-August. Medium-speed meteors. Their peak falls at first quarter Moon this year.

α Capricornids: Slow meteors, occasionally beautifully bright, but their activity is never very high. The waxing gibbous Moon sets before 23h UT for most of Britain at their peak, allowing some useful coverage.

Perseids: From 1988-1999, the Perseids produced a double maximum, but from 2000-2003 only one main peak was seen. The primary peak was associated with Comet 109P/Swift-Tuttle's most recent perihelion in 1992 (period ~135 years). A strong, early peak recurred in 2004, followed by several years of ZHR ~80-90 maxima until the quite strong (ZHR ~120) maximum in 2008, which occurred significantly later than any other recent Perseid peak. The normal maximum in 2010 is due on August 12 between 17:30-20h UT. However, enhanced rates adding between a few tens to a hundred meteors per hour to the ZHR then, may happen around 09h UT on August 12, perhaps preceded by a further minor peak (this may be too weak to be detectable) near 05h UT. All these timings are in daytime for Britain sadly, but the waning gibbous Moon will ruin both August 11-12 and 12-13 anyway. Swift meteors, often trained.

κ Cygnid: Rates are generally low, but occasional bright fireballs (possibly in periodic bursts every 6 to 7 years) have been seen from this source. Slow meteors. New Moon is on August 20, so well-placed for observers.

α Aurigids: Probably associated with Comet Kiess, last seen in 1911, whose period is around 2500 years, unusually long to produce what appears to be an annual shower. The α Aurigids are part of a series of suspected minor showers with radiants in Aur, Cas, Per, Ari and Tri during the early autumn, an area of sky best-observed only after ~23h UT from Britain. All appear to be most active from late August to mid-September, and need more investigation, especially after the moonlit, but bright-meteor, α Aurigid outburst on 2007 September 1 (ZHRs ~130). The 2007 event was predicted in advance, but other unexpected outbursts have happened too, giving estimated ZHRs of ~30-40 in 1935, 1986 and 1994. Very swift meteors. The maximum is due around 01h UT on September 1 in 2010, with a waxing gibbous Moon that will set between roughly 01:00-01:30 UT for most UK sites.

September Perseids: Another near-Auriga shower of very swift meteors, but very unfavourably-placed with a waning gibbous Moon for their maximum. An unexpected bright-meteor outburst occurred on 2008 September 9 from a radiant some way from the expected September Perseid one, in Perseus near RA 03h10m, Dec +39°. Early claims suggested this was due to the September Perseids, but these remain unproven, and some alternative source seems at least as likely, perhaps the little-known ε Perseids.

δ Aurigids: Their activity follows on directly from the September Perseids, and they are identical meteors, but their orbital parameters seem to be different to the September Perseids. Their peak is very ill-defined. It may last from Sep 24 to Oct 4, giving low ZHRs. September 29 is simply the midpoint date for this range, not the expected true maximum. Late September's waxing gibbous Moon allows coverage of part of this spell, till too near full on October 4.

Draconids: Past showers have typically happened only when their parent comet, 21P/Giacobini-Zinner (period around 6.6 years), was at perihelion in the autumn, as in 1998, when short-lived ZHRs of circa 700 occurred. Other returns have given rates up to storm levels (the last storm was in 1946). A largely unexpected outburst happened in 2005 (the comet returned most recently that July), so worth checking in most years just in case. Very slow meteors, and apparently very fragile meteoroids. Possible maximum timings in 2010 fall between October 8, 08:45 to October 9, 01:30 UT, with a problematic waning gibbous Moon.

Orionids: Linked to Comet 1P/Halley, like their May counterpart, the η Aquarids. ZHRs are usually quite good for 2-3 nights centred on their peak, and may be about 30 this year from a recent IMO analysis. Activity could be still stronger, following the higher returns (ZHRs ~40-80) in 2006, 2007 and 2008, when such rates persisted for two or more nights at these levels, though sadly, no repeat is expected for 2010 on theoretical grounds. A quite strong sub-maximum has been noted occasionally around October 17-18 as well (most recently in 1998). New Moon on October 18 is excellent news for seeing whatever happens. Very swift meteors, with good trains.

Southern & Northern Taurids: Both showers are associated with weakly-active Comet 2P/Encke, which has the shortest orbital period of any comet known (3.3 years). The two showers give low rates, but occasional fireballs spice up their prospects, and in some years (as last in 2005) these can be especially prevalent in late October to early November, during some of their "swarm" returns. The most recent "swarm" event was in 2008, which produced good rates for a few days during this spell, but no unusual fireball numbers. The next "swarm" return is not till 2012. Full Moon this autumn is on November 2, leaving darker skies only for the Northern Taurid maximum. Slow meteors.

Leonids: Possibly strong, maybe even storm-level, Leonid activity has been predicted for this year, with best rates probably happening at some stage between roughly 21h-22h UT on November 17. ZHRs are uncertain, possibly around the 120-140 mark, but maybe as high as ~1000-1500, and probably set against a background of ZHRs ~20-40+ from about 06:30 UT on November 17 till roughly 00:30 UT on the 18th. Other submaxima may occur too, near 07:30 (ZHRs ~200+?) and 09h UT (~25-30?) on the 17th, 00h (~15?) and 19h UT (~10-15, but faint meteors) on the 18th. This does not exclude other unexpected peaks! New Moon on November 16 creates perfect viewing conditions, but the probably strongest peak will be too early for the UK if it keeps to time, as the radiant rises here at about 23h UT, and can be usefully-observed only after midnight. The proximity of the shower's parent comet 55P/Tempel-Tuttle helped produce the strong to storm returns in 1998-2002. It was at perihelion last in 1998 (period 33 years). Very swift meteors, often trained.

α Monocerotids: This shower had a suspected periodicity of ten years between its high, short-lived outbursts. The most recent one was in 1995, very well-seen across Europe. Estimated ZHRs were ~420, but for only about five minutes; the whole outburst took less than half an hour! However, no outburst recurred in 2005, and studies now suggest no further strong activity is likely before 2043, though there is the possibility of a weak showing in 2019. Observers need to be alert every year, just in case of something unanticipated, however. Very swift meteors, slightly slower than the Leonids. The maximum is due at 15:25 UT on 2010 November 21, in daylight for the UK, but otherwise ideal, with only a waxing crescent Moon. The radiant can be observed throughout the second half of the night, after rising for Britain near 22h UT.

Geminids: Associated with asteroid 3200 Phaethon, rather than a comet, and their meteoroids seem to be rather denser than those in most meteor showers too. Good rates can be seen for around two nights over their peak, but drop away very quickly after the maximum. Unlike many meteor showers, they are easily-observed throughout the night. Regular British observers often consider them the best, reliable, annual shower of the year visible here at present, though the winter weather can be problematic. Medium-speed, often bright, meteors. Their peak is due on 2010 December 14, within 2h20m of 05h UT, good for UK watchers, and perfect with new Moon on December 16.

Ursids: Linked with Comet 8P/Tuttle (period around 13.5 years; last at perihelion in late January 2008). Their peak rates can be quite variable, from ~10-50+, with especially good activity last in 1986. Theoretical work has suggested some enhancements occur about six years after the comet's perihelion, others near years when the comet is at perihelion (though why this latter should happen is unclear, as the comet's orbit currently passes a little outside the Earth's orbit). These theoretical considerations are only a rough guide to reality however, as enhanced ZHRs between ~25-40 were reported from 1988, 1994, 2000, 2006, 2007 and 2010, since the stronger 1986 return. The peak should occur on December 22 this year, but it may fall around 07:15 UT (ZHRs ~15?) or between 13:30 to 16h UT (ZHRs ~10-15?), in either case with a favourable waxing crescent Moon. The circumpolar radiant means they can be observed all night from Britain.

Coma Berenicids: A poorly-known minor shower, badly in need of regular observing. Recent video investigations have suggested the Coma activity may actually originate from a radiant approximately 15° west of the position stated here. Very swift meteors. Unhappily, the probable peak is well-timed only for a full Moon.