Meteor Activity 2021 April to 2022 March
Edited by Tracie Heywood
This guide describes the prospects for the major meteor showers and for a number of minor meteor showers during the interval from 2021 April to 2022 March. It is compiled with visual observers in mind, but should also be useful for imagers and radio observers.
Accompanying each individual meteor shower overview is a chart which shows the location and movement of the meteor shower radiant during the activity period. In reality, of course, the shower radiant isn’t a single point but is spread over several degrees of sky. However, for most meteor showers a radiant diameter of a few degrees can be assumed.
Expected Highlights:
With the Full Moons in the later part of the year occurring in the third week of each month, several major meteor showers will have their maxima badly affected by moonlight – the Delta Aquarids-S, Orionids and Leonids are particularly badly affected. The Lyrids, Geminids and Ursids will also suffer moonlight interference for most of the night.
The situation is much better for the Perseids in August and for the Quadrantids of January 2022. Moonlight circumstances are also good for a possible Alpha Aurigid outburst on August 31st.
Background
How accurate are published meteor shower listings?
Some are more reliable than others.
Many older listings are severely contaminated by the inclusion of spurious minor showers whose existence was based on a combination of chance lining-ups of sporadic meteors and of misidentified shower meteors. Few of these minor showers have been confirmed by the more recent and more accurate video monitoring.
Although some meteor shower listings have been updated to take into account more recent data, there are others that have not. Prior to 2019, for example, that the list of meteor showers included in the BAA Handbook had not been updated for over 20 years and still included several minor showers that were not been confirmed by more recent work … but the 2019 update brought it up to date.
Another factor to bear in mind is that the software packages used by video observers make use of (largely unseen) meteor shower listings. Although these are most likely based on recent data, some of these shower lists are based on stricter criteria than are others. Some software packages also use rather too generous activity periods. In particular, there is the risk that observers may be too trusting of software-reported shower classifications and may treat them with insufficient caution, especially when dealing with single-station detections.
Dates of maxima for major showers are well established. Do bear in mind, however, that whereas some showers, such as the Quadrantids and Perseids, have single well-defined peaks, others, such as the Taurids merely produce sustained activity over many weeks. Although activity may be slightly higher on some nights than on others, it is generally unhelpful to describe such nights as “maxima” as this is likely to discourage less knowledgeable observers from monitoring activity on other nights.
In a few cases, the time of maximum is quoted to the nearest hour … but the time quoted may still differ by an hour or more depending on which listing you look at. Treat the times specified as a quite good guide, but do remember that some of these meteor showers will have sharper peaks than will others. Observers will see a large drop in rates within only a few hours after the sharp Quadrantid peak, but a somewhat smaller drop in the hours immediately following the broader peaks of the Perseids and Geminids.
And finally, also bear in mind that, due to mass sorting of particles in the their meteoroid stream, some meteor showers show differently timed peaks for bright meteors, for the more “routine” shooting stars and for radio reflections.
How different will it be for imagers?
The observing prospects will be largely similar for imagers using DSLR cameras or video cameras. Video observers will, however, be able to cope better with moonlit conditions.
Video imaging also makes it easier to get an accurate measurement of the speed of a meteor and thus to differentiate between meteors that line up by chance with a radiant and those that also possess the expected speed for the meteor shower involved. As a result, video imaging can identify low level activity from meteor showers beyond the activity date range quoted for visual observers.
Of course, coincidences can still occur (as is seen for the similarly speeded Quadrantids and December Alpha Draconids at the turn of the year) and so multi-station imaging of a meteor is required in order to be absolutely certain in the shower identification.
How different will it be for radio observers?
Radio observations can also detect reflections from particles smaller than those that produce naked-eye meteors.
Thus, the richness of a meteor shower in bright meteors or in faint meteors relative to the sporadic background gives a big clue as to the expectations for radio monitoring. This is particularly relevant during the first ten days of August when considering the relative radio rates of the Southern Delta Aquarids and the Perseids. For naked-eye observers, the Perseids are by this time out-performing the southern Delta Aquarids. The latter, being relatively more rich in smaller particles (fainter meteors), are, however, by far the stronger shower in radio monitoring.
Individual Meteor Shower overviews
Early year meteor activity
Once the Quadrantid peak of early January has subsided (see later for 2020 details), night time meteor rates become rather low for northern hemisphere observers.
From mid-February to early May there are a number of minor showers with radiants close to the ecliptic. Older sources collectively refer to these as the Virginids, sometimes also listing individual maxima including the Delta Leonids (max Feb 26), the Alpha Virginids (max Apr 11-12) and the Gamma Virginids (max Apr 14).
More recent lists treat this activity as being part of a “Spring Antihelion Source”, the “Antihelion” reference being due to the activity originating from an area of sky located about 180 degrees from the position of the Sun. The location of this “source” thus gradually moves along the ecliptic from Leo in February, through Virgo in March, Libra in April and reaches Scorpius in May
New Moon in 2019 occurs on March 6th, April 5th and May 4th.
Lyrids max Apr 22d 13h UT
Lyrid activity is apparent to visual observers from Apr 18-25 each year.
The Lyrids are the main night time meteor shower of the spring months for northern hemisphere observers. They don’t usually produce observed rates comparable with major showers that occur later in the year, but 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.
For observers at northern latitudes, the Lyrid radiant is above the horizon all night. Observed rates gradually pick up as the radiant altitude increases during the night, so meteor watches after midnight are the most productive.
The accompanying diagram shows the position of the Lyrid radiant, with the UK horizon shown for the early hours of the morning.
The best observed rates are likely to be seen late in the night of April 21-22 (Wed-Thu).
Disappointing news for the 2021 maximum is that although the Moon has only just passed First Quarter (on April 20th) its northerly declination (in Leo) means that it will stay around almost until dawn so there will be hardly any period of moonlight-free sky.
Eta Aquarids max May 5-6
This shower, resulting from the Earth’s post-perihelion encounter with the meteoroid stream of comet Halley, is active from late April to mid-May and produces higher peak ZHR values than do the Lyrids. Analyses by the IMO indicate that the ZHR generally remains over 30 from May 3-10. 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, in most years, observers at northern latitudes can only expect low observed rates.
In 2013 enhanced Eta Aquarid rates were seen due to the Earth encountering a number of meteor trails from 8-11 centuries ago. Some UK based observers who had never before seen an Eta Aquarid saw several in 2013. Normal rates were seen in 2014-2020. There was a suggestion of the presence of a 12-year periodicity in Eta Aquarid rates, possibly Jupiter-related, with the next “peak period” due during 2020-2022. More recent studies have, however, called this into question.
In 2021, the Eta Aquarids will peak with the Moon having passed Last Quarter. It should always be remembered, however, that for observers in northern latitudes, encroaching morning twilight tends to have more effect on observed Eta Aquarid rates than does any moonlight.
The Eta Aquarid radiant is in northern Aquarius. The accompanying diagram shows its position around the date of maximum.
Other Spring meteor activity
Lyrids and Eta Aquarids aside, night time meteor rates become rather low for northern hemisphere observers during the Spring months.
Throughout this period, there are a number of minor showers with radiants close to the ecliptic. Older sources collectively refer to these as the Virginids, sometimes also listing individual sub-stream maxima.
More recent lists treat this activity as being part of a “Spring Antihelion Source”, the “Antihelion” reference being due to the activity originating from an area of sky located about 180 degrees from the position of the Sun. The location of this “source” thus gradually moves along the ecliptic from Leo in February, through Virgo in March, Libra in April and reaches Scorpius in May
New Moon in 2021 occurs on April 12th, May 11th and June 10th.
Mid-year Daytime showers
For observers at northern latitudes the Eta Aquarids are almost a daytime-only shower. Several other meteor showers during May and June are even less well placed for night time observation. The radiants of these latter showers 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 level and radiant location information for these showers is often poorly known, but the most active appear to be the Omicron Cetids (max May 20), the Arietids (max June 7), the Zeta Perseids (max June 9) and the Beta Taurids (max June 28). The indications are that the Arietids and Zeta Perseids are comparable in strength with the Lyrids or Orionids, while the Omicron Cetids and Beta Taurids are comparable with the autumn’s night time Taurid showers.
June Bootids max June 23?
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 last at perihelion in January 2015 and the next perihelion isn’t due to occur until May 2021. However, there is no evidence that recent outbursts have been related to the position of the comet. It is worthwhile monitoring this shower’s activity each year in case further outbursts occur.
The June Bootid radiant lies in a similar area of sky to the Quadrantid radiant of early January, but there is some uncertainty as to the exact location of the shower radiant, with recent reports merely describing the activity as originating from northern Bootes. The accompanying chart shows the position reported for the 2004 outburst. Early 20th century reports had placed the radiant a few degrees further east (left) of this.
First Quarter in 2021 occurs on June 18th, with Full Moon on June 24th. From the more northerly latitudes (including the UK), however, the all-night twilight tends to be the main problem for observers.
Gamma Draconids max July 28
Night-time sporadic activity picks up in July.
Older meteor shower lists sometimes included minor showers such as the Alpha Cygnids (active throughout the month and into early August, radiant 21h00m, +48) and the Lacertids (active later in the month, radiant 22h05m, +37). Neither shower seemed to have any clearly defined maxima and it is possible/likely that the meteors assigned to these showers were merely chance lining-ups of sporadic meteors with their “radiants”. Indeed, neither shower is listed in the IMO’s current working list of meteor showers.
The Gamma Draconids usually only provide low level activity. During the night of 2016 July 27-28, however, an outburst was observed, with most of the activity occurring during the hour of 23:30-00:30 UT. NEMETODE observers determined the radiant position to be RA 16h43m, Dec +50.5.
The accompanying chart shows the position of the meteor shower radiant for the night of maximum. Limited data means that the extent of the activity period and the night to night motion of the radiant are poorly known.
With the Full Moon occurring on July 27th, monitoring for Gamma Draconid activity in 2021 will be greatly hindered by moonlight.
Summer Antihelion Source
Late July and much of August features activity from a number of radiants in the Capricornus-Aquarius-Pisces region, with rates peaking at around the end of July.
Showers that have often been listed include the Delta Aquarids (N and S), the Iota Aquarids (N and S), the Capricornids, the Alpha Capricornids and the Pisces Austrinids. Rather confusingly, some sources referred to the Alpha Capricornids as the Capricornids, whilst others (including the BAA Handbook) were using the term “Capricornids” to describe a minor shower peaking around July 25 ! The proximity on the sky of several of these radiants made it difficult for visual observers to accurately assign meteors to individual radiants, especially from the latitude of the UK from where the radiants are always quite low in the sky.
There was much confusion. The IMO, in an attempt to clarify the situation, has grouped together the most of these showers into what it refers to as the “Summer Antihelion Source”, the “radiant area” of which slowly moves from Capricornus in July to Pisces in September. Rates from this “source” are never high, but do help enhance the overall meteor activity levels at this time of the year.
Only three showers are still listed separately by the IMO : the southern Delta Aquarids, the Alpha Capricornids and the Piscis Austrinids. However, the southerly declination of the latter means that it is only really separable for observers at southern latitudes.
In 2021, New Moon occurs on July 10th and August 8th, with Full Moon occurring on July 24th.
Southern Delta Aquarids max July 29
Of these southern radiants, it is the southern Delta Aquarids that produce the highest meteor rates. The activity period lasts from mid-July to mid-August, with peak activity occurring around July 29th.
This meteor shower produces few bright meteors but is rich in faint meteors relative to the sporadic background. It is particularly strong in radio observations. Indeed, during the first week of August it usually appears stronger than the Perseids in maps of radio meteor activity.
The highest visual rates are likely to be seen in the early hours of the morning when Aquarius is highest in the sky. The accompanying diagram shows the location of the radiant, with the UK horizon shown for around 01h UT.
With the Full Moon occurring on July 24th, the maximum of the southern Delta Aquarids in 2021 will suffer from severe moonlight interference. During the night of July 29-30, the waning gibbous Moon, near the Pisces-Cetus border, will rise only around an hour after it gets dark.
Alpha Capricornids max Aug 1
The Alpha Capricornids are active from mid-July to mid-August. They produce lower rates than the southern Delta Aquarids but do have a reputation for producing a fair number of slow moving (a mere 24km/s) and colourful bright meteors. The peak does not seem to be particularly sharp, with quoted dates of maxima ranging from July 29th to August 3rd, depending on which source you read.
The highest rates are likely to be seen around the middle of the night when Capricornus is highest in the sky. The accompanying diagram shows the position of the Alpha Capricornid radiant, with the UK horizon shown for the middle of the night.
With the Moon having passed through Last Quarter on July 31st, moonlight interference will affect Alpha Capricornid observations after midnight. During the night of Aug 1-2, the thick-crescent waning Moon will be located near the Aries-Taurus border and will rise midway through the night.
Perseids max Aug 12d 19-22h UT
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. In addition, the Perseids are rich in bright meteors, with more than a third leaving persistent trains.
Perseid activity can be seen from the last ten days 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. In some years, when the Earth encounters dust trails from old returns of the parent comet, there can be additional short-lived Perseid peaks.
In 2016, a strong enhancement of Perseid rates occurred during the late evening of Aug 11th. This was related to a 12-year periodicity in Perseid rates and continued the sequence of enhanced Perseid rates previously seen in 1968, 1980, 1992 and 2004. No significant enhancements are predicted for 2021.
Both Aug 11-12 (Wed-Thu) and Aug 12-13 (Thu-Fri) should be good nights for observing the Perseids from the UK, with the predicted ZHR peak near the start of the latter. The pre-dawn period of the former sees the radiant high in the sky, while the evening of the latter though close to the expected peak time has the radiant lower down. Quite good rates should also be seen during Aug 10-11 (Tue-Wed) and during Aug 13-14 (Fri-Sat).
With New Moon occurring on August 8th, most of the rise towards Perseid maximum will have minimal moonlight interference. Even at Perseid maximum, the crescent Moon, in Virgo will be setting by the time that the sky gets dark enough for meteor observing.
The accompanying diagram shows the position of the Perseid radiant. Note that it moves a considerable distance across the sky between late July and maximum night. Observed Perseid rates increase as the night progresses and the radiant altitude increases.
Kappa Cygnids max Aug 18
Sporadic 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 Summer Antihelion source. Some early Alpha Aurigid activity can be seen late in the month.
The most reliable shower is the Kappa Cygnids which start around the time of the Perseid peak and reach maximum around August 18th. Although their rates are generally low, enhanced activity was reported in 2007 and 2014. Indeed, there seems to be growing evidence that the Kappa Cygnids produce these higher rates at 7-year intervals. The shower also has a reputation for producing quite a few fireballs. Some sources also list a second Kappa Cygnid maximum on August 26th.
The accompanying diagram shows the location of the radiant.
Moonlight circumstances for the Kappa Cygnids in 2021 favour the post-midnight period, with First Quarter occurring on August 15th and Full Moon on August 22nd.
Alpha Aurigids max Aug 31d 21.5h?
This minor shower is active each year and produced brief outbursts, reaching ZHRs of 30-50, being observed in 1935, 1986, 1994, 2007 and 2019. Given the briefness of these outbursts, it is quite probable that other outbursts may have been missed.
The accompanying diagram shows the position of the radiant, with the UK horizon shown for around 01h UT. Observed rates will most likely be low, but will increase as the night progresses and the radiant altitude increases.
For 2021, modelling by Sato, Lyytinen and Vaubaillon, indicates that an outburst may occur at around 21:35 UT on August 31st. The radiant will be quite low in the northern sky, but it is certainly worth monitoring for activity.
With Last Quarter occurring on August 30th, moonlight circumstances are fairly favourable for the 2021 Alpha Aurigids.
September Perseids max Sep 9
This minor shower is active each year and is sometimes also referred to as the Epsilon Perseids, despite its radiant being close to Algol and somewhat distant from the star epsilon Persei
In 2013, imagers recorded this shower producing a stronger than usual display. There were also reports of an earlier outburst in 2008.
Observed rates tend to increase as the night progresses and the radiant altitude increases. The accompanying diagram shows the location of the radiant, with the UK horizon shown for 23h UT.
Moonlight circumstances are favourable in 2021 for the September Perseids, with New Moon occurring on September 7th
Early Autumn Antihelion source
Sporadic activity is also high in September and, again, numerous minor showers have been reported, although not as many as for August, probably because there are usually fewer observers active.
Be aware that in many cases the names allocated to these minor showers varies from one source to the next! The more reliable minor showers include the Alpha Aurigids (continuing from August, see above), the September (Epsilon) Perseids (see above) and the Piscids (max Sep 8-9, Sep 21). More recent sources usually include the Piscids as part of the “Antihelion Source” (whereas later autumn ecliptic based radiants are allocated to the Taurid complex). A chi Cygnid minor shower (radiant RA 22h00m, Dec +31), peaking near Sep 14-15, has also been reported in recent years.
New Moon in 2021 occurs on September 7th, with Full Moon occurring on September 21st.
October Camelopardalids max Oct 5-6
This minor shower has produced outbursts of activity on several occasions in recent years, via short-lived peaks reaching ZHRs of around 5. A recurrence in 2021 would produce a peak around 19h-22h UT on October 5th, with the radiant in the north eastern sky.
Our knowledge of this shower remains limited, however, and additional peaks at other times cannot be ruled out
The accompanying diagram shows the position of the radiant as seen during previous outbursts.
Draconids (Giacobinids) max Oct 8d 23-24h UT?
21P/Giacobini-Zinner, the parent comet of this shower, last passed through perihelion in February 2012 and is due to pass through perihelion again on September 10th 2018.
Observations of the Earth’s closest passage to the comet’s orbit at around 2011 October 8 were seriously impacted by a bright moonlight, but a short-lived outburst to a ZHR of 250-300 was seen. High Draconid rates were not expected in 2012, but some radio and radar observations did suggest that a significant outburst occurred at around 16h-17h UT on October 8th. The extent to which the shower produced a visual display is unclear due to the poor observing conditions for the visual observers who were active at that time. It was suggested that the visual ZHR may have exceeded 100, but this was very uncertain. Nothing exceptional was reported during 2013-2017.
Another outburst occurred between 22h and 0h UT during the night of 2018 October 8-9, with the peak ZHR probably exceeding 100 (somewhat better than predicted, though producing few bright meteors). No significant enhancements are predicted for 2021.
The radiant lies near the head of Draco, as can be seen in the accompanying diagram. It is quite high in the sky for observers at northern latitudes at the start of the night and still reasonably high in the north west by midnight. Draconid meteors are relatively slow moving (a mere 21 km/s) - a feature which helps differentiate them from any sporadic meteors that might by chance line up with the radiant.
Moonlight circumstances are favourable for observations of the 2021 Draconids, with New Moon occurring on October 6th.
Orionids max Oct 21-23
Although there is low level activity from the start of the month, Orionid activity only becomes obvious to visual observers from around Oct 14, lasting until the end of the month. A broad maximum occurs between Oct 21 and Oct 23 - however, even within this period there can be several peaks and troughs in the activity levels. Further away from the normal maximum period, in both 1993 and 1998, observers in Europe noted a significant Orionid peak during the night of October 17-18.
The Orionids, which are the result of the Earth’s pre-perihelion encounter with the meteoroid stream of comet 1P/Halley, sometimes brings surprises such as the unusually high rates seen during the night of 2006 Oct 21-22. Enhanced rates were also seen in 2008 and 2009, but more recent years have produced more “normal” Orionid rates.
The radiant position at maximum is RA 06h24m, Dec +15 (on the border of Gemini and Orion). Its motion over the period of Orionid activity can be seen in the accompanying diagram.
Be aware that the Orionid radiant does not rise until around 21h UT (10pm BST) and so no Orionids will be seen before that time. Orionid rates are likely to be highest late in the night when the radiant is high in the sky.
Moonlight circumstances for the 2021 Orionid peak are unfavourable, with Full Moon occurring on October 20th. Between Oct 21 and Oct 23, the Gibbous Moon moves from Aries into Taurus is rising well before the Orionid radiant.
Taurids broad max mid Oct-early Nov
Taurid activity, which is related to the meteoroid stream of comet 2P/Encke, lasts throughout October and November. Some Taurid activity will be visible during Orionid meteor watches in October and Leonid meteor watches in November. Indeed, the Taurid radiants produce relatively slow meteors (28 km/s) in contrast with the faster Orionids (67 km/s) and Leonids (71 km/s).
The accompanying diagram shows the movement off the Taurid radiants during the shower’s activity period. Note that the Taurid radiants are highest in the sky around the middle of the night – a more convenient timing than for many other meteor showers.
Although individual dates of maxima are often quoted for the northern and southern Taurids, this is not helpful as it leads many Sky Diary authors to quote these dates as if they represent sharp maxima similar to those seen for showers such as the Quadrantids or Perseids. This, in turn, risks discouraging people from observing at other times. In reality, the Taurids do not have sharp peaks in the same sense as seen in many major showers and it makes more sense to treat the shower as showing a broad maximum from mid-October to early November. The southern radiant tends to be the more active during October, whilst the northern radiant is the more active during November. Expect to see some Taurids during Orionid meteor watches.
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 and analyses by David Asher supported the idea of a Taurid “swarm” that the Earth encounters every few years. Results from 2008 showed some enhancement in Taurid rates, but few extra fireballs. Results for the moonlit 2012 ‘swarm’ encounter were disappointing. Better rates were reported for the 2015 encounter, but there seem to have been no reports of exceptional activity in 2019.
New Moon in 2021 occurs on October 6th and November 4th, with Full Moon occurring on October 20th and November 19th. Thus, the best period for seeing Taurids in 2021 will be in late October and early November.
Leonids max Nov 17-18
Leonid activity last from Nov 14-21 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 as well as a prolonged outburst of bright meteors on November 17th 1998 (popularly referred to as the “fireball storm”, although ZHRs probably only reached around 250).
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 November 17. Observing conditions were fairly unfavourable in 2010, but reported observations did indicate a ZHR over 20 - and so well above the rates usually quoted for years between perihelion returns of the parent comet.
No significant enhancement of Leonid rates is predicted for 2021.
The position of the Leonid radiant is shown in the accompanying diagram, with the UK horizon shown for around 03h UT. Be aware that, for UK based observers, the radiant doesn’t rise until around 22:30 UT and so no Leonids will be seen during the early evening. The highest observed rates are likely to be seen late in the night when the radiant is high in the sky.
Moonlight circumstances are unfavourable for the 2021 Leonids, with Full Moon occurring on November 19th.
December Alpha Draconids max Dec 8
There has been some confusion in recent years regarding the activity period of this minor shower.
Originally, it was assigned a peak date of December 8th. There was, however, a later claim of a second peak from a similar radiant position on December 30th and to complicate things further, some software programs used in conjunction with video imaging systems have been assigning many (single-station observed) meteors in early January to this minor shower. Two factors are probably responsible, at least in part, for this apparent later activity. One is that the shower is assigned a large radiant diameter of 9 degrees. The other is that nearby is the radiant of the Quadrantid meteor shower - this is active from late December to mid-January and produces meteors with a similar speed. Multi-station analyses, when possible, tend to re-assign most of these later single-station “December Alpha Draconids” to the Quadrantids.
The accompanying chart shows the radiant location for the established peak of Dec 8-9, with the horizon shown as for the middle of the night for UK based observers.
Moonlight circumstances in 2021 are quite favourable for the December 8th peak, with New Moon having occurred on December 4th.
Sigma Hydrids max Dec 11
This minor shower is active in mid-December and although only producing low activity rates, does over its two-week activity period produce a significant overall number of meteors. Peak rates occur around December 11th.
The accompanying chart shows the radiant location below the head of Hydra, with the UK horizon shown for the middle of the night. Note that the radiant doesn’t rise above the horizon until mid-evening. The best observed rates occur after midnight, when the radiant is climbing higher in the sky.
The 2021 maximum of this shower occurs with the Moon at First Quarter. By the time that the radiant has gained a good altitude, the Moon will have set.
Geminids broad max Dec 14d 02h-07h UT
Geminid activity is apparent to visual observers from December 7-16, with the best rates likely to be seen during the night of Dec 13-14 (Mon-Tue). The Geminid ZHR is also likely to be quite high during Dec 12-13 (Sun-Mon), but will be falling by the night of Dec 14-15 (Tue-Wed) and will be much lower by the night of Dec 15-16.
The Geminids are the meteor shower that produce the highest reliable rates year on year and only lose out in popularity to the Perseids because August nights tend to be less cold. Results from recent years have shown the peak Geminid ZHR to usually be over 100 and to remain above 70 per hour for nearly 24 hours. The shower’s profile also appears to be evolving from year to year.
The time of maximum specified above is favourable for observers at European longitudes and also quite good for observers in North America.
Mass sorting within the meteoroid stream leads to Geminid radio rates peaking many hours ahead of the visual peak time specified above, with bright Geminids peaking several hours later.
The location of the Geminid radiant is shown in the accompanying diagram. For observers at northern temperate latitudes, is above the horizon all night and highest shortly before 2am.
Moonlight circumstances for the 2021 Geminids are rather unfavourable with a 77% illuminated gibbous Moon located near the Pisces-Cetus-Aries border and not setting until around 3am on the morning of Dec 14th. This will, however, still leave around 3 hours of moonlight-free skies late in the night.
The Geminids are rich in bright meteors but, being associated with a rocky asteroid 3200 Phaethon rather than an icy comet, produce few trained meteors. Being of medium speed (35 km/s), individual Geminids tend to be more clearly seen by observers than do meteors from the faster showers (such as the Perseids and Leonids).
Coma Berenicids max Dec 15 & December Leo Minorids max Dec 19
These minor showers are active throughout most of December and January. They also only produce low activity rates, but over their eight-week activity period do produce a significant overall number of meteors. Note that some sources no longer list the December Leo Minorids as a separate shower, but instead merge them with the Coma Berenicids.
The accompanying chart shows the locations of the radiants involved, with the UK horizon shown for around 02h UT. Both showers produce their best rates late in the night when their radiants are high in the sky.
With Full Moon in 2021 occurring on December 19th, the maximum of the December Leo Minorids will be very unfavourable. Coma Berenicid maximum is also unfavourable, with a 85% illuminated Moon near the Pisces/Aries/Cetus border, but there will at least be a short (2-hour) moonlight-free spell late in the night.
Ursids max Dec 22-23
Ursid activity lasts from approx Dec 17-25. The Ursid radiant is located fairly close to Beta UMi, as can be seen in the accompanying diagram. It is circumpolar for most northern hemisphere observers and is highest in the sky late in the night.
High rates were recorded from the Ursids in 1945, 1982 ,1986, 2000, 2004, 2006 and 2014. There were also reports of higher than usual Ursid radio rates in 2016 (see IMO website). It is suspected that other such peaks may have been missed due to a lack of observations. A number of predictions have been made for enhancements due to encounters with dust trails from the 8th and 9th centuries during 2020 December 22nd, but the timings for these are quite uncertain.
With Full Moon having occurred on December 19th, there will be a shortish moonlight free spell during the early evening on the night of maximum, but bright moonlight from the 87% illuminated Moon near the Cancer-Leo border, will be a major issue for most of the night.
Quadrantids 2022 03d 20h-21h UT
(see also the earlier note on the December Alpha Draconids)
The Quadrantid radiant, lying at Dec +49 in a rather bland area of sky between Draco, Bootes and Ursa Major, 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 accompanying diagram shows its location, with the UK horizon shown for around 22h UT.
The maximum is usually rather narrow. Be aware, however, that due to mass-sorting within the meteoroid stream, peak radio rates (smaller particles) will most likely occur several hours before the time quoted above and peak rates for bright meteors (larger particles) may be later.
Peak visual rates vary from year to year. The ZHR for the 2012 and 2017 peaks only seemed to reach around 80 whereas the 2009 peak was broader than usual with the ZHR being above 100 for nearly 12 hours. There were indications that the 2020 Quadrantids may have peaked earlier than the predicted time of 08h-09h UT.
The ideal visual observing circumstances involve the peak occurring during the hours of darkness, with the radiant high in the pre-dawn sky and with the Moon absent.
Two of these conditions will be met in 2022 for UK-based observers. New Moon is on Jan 2nd and so moonlight will not be an issue. In addition, the peak occurs during the hours of darkness in the UK. Unfortunately, the peak is also occurring at around the time that the radiant is lowest in the northern sky and this will reduce observed rates somewhat. Circumstances will be better for observers in eastern Asia, with the radiant high in the pre-dawn sky at the time of the peak.
Other early year meteor activity
Once the Quadrantid peak of early January has subsided, night time meteor rates become rather low for northern hemisphere observers.
From mid-February to early May, there are a number of minor showers with radiants close to the ecliptic. Older sources collectively refer to these as the Virginids, sometimes also listing individual sub-stream maxima.
More recent lists treat this activity as being part of a “Spring Antihelion Source”, the “Antihelion” reference being due to the activity originating from an area of sky located about 180 degrees from the position of the Sun. The location of this “source” thus gradually moves along the ecliptic from Leo in February, through Virgo in March, Libra in April and reaches Scorpius in May
New Moon in 2022 occurs on March 2nd, April 1st and April 30th.