By Tracie Heywood
- Visual Meteor Showers List (table)
- Shower Notes
- Antihelion Source (ANT) Radiant Centre Locations (table)
Finding out which meteor showers are active each month can be a challenge. Some published lists haven’t been updated for over 20 years and don’t take into account more recent and more accurate video observations. Some more recent lists go too far and extend the activity dates of meteor showers to those detectable using video methods but well beyond those during which the meteor shower will be evident visually.
The list is largely based on the 2014 revision of the International Meteor Organization’s (IMO’s) Working List of Visual Meteor Showers, which itself is based on “A Comprehensive List of Meteor Showers Obtained from 10 Years of Observations with the IMO Video Meteor Network” by Sirko Molau and Jurgen Rendtel. Amendments continue to be made using reliable data to ensure the information remains as fully up-to-date as possible, since as we have discovered in the last two decades, meteor showers are not fixed things, but are constantly changing, some faster than others. The details presented here take into account the latest updates presented in the 2017 IMO Meteor Shower Calendar .
SPA observers are encouraged to cover these showers because they are known to be genuinely active at the present time, and they produce visually-detectable rates.
Diurnal and Seasonal Variations
In addition to the variations in meteor rates due to major meteor showers listed later, there are also general daily and seasonal trends in meteor rates. In the same way as the front of your coat gets wetter than the back as you walk through the rain, so the side of the Earth facing the direction the Earth is heading its orbit encounters more meteors than the backward looking side. In practice this means that the background sporadic meteor rates are lowest at around 6pm each day and then steadily rise through the night towards their peak at around 6am. The seasonal variation occurs because the direction in which the Earth is moving lies on the ecliptic 90 degrees behind the location of the Sun. Around the spring equinox, this is in Sagittarius and so never gets very high in the sky from the UK and so sporadic meteor rates are low. By the autumn equinox, this has moved to the Taurus/Gemini area, is therefore much higher in the sky, and hence we see higher sporadic meteor rates.
Visual Meteor Showers List
The activity dates given for the major showers in the table below are those between which the shower is likely to be apparent to a naked eye observer. Outlying members of the meteor stream can be detected beyond these dates via imaging techniques.
|Shower name||IMO shower|
|Radiant position at maximum RA Dec||Radiant Daily motion RA Dec||Speed (km/s)|
|Quadrantids||QUA||Jan 1-6||Jan 3d 14h||80-120||15h20m||49°||2.4m||-0.2°||41 km/s|
|Lyrids||LYR||Apr 18-25||Apr 22d 11h||18||18h04m||34°||4.4m||0.0°||49 km/s|
|η Aquarids||ETA||Apr 19-May 28||May 5-6||70||22h32m||-01°||3.5m||0.4°||66 km/s|
|June Boötids||JBO||Jun 22-Jul 2||Jun 27?||0-100+||14h56m||48°||1.6m||-0.2°||18 km/s|
|δ Aquarids||SDA||Jul 15-Aug 20||Jul 29||20||22h36m||-16°||3.0m||0.2°||40 km/s|
|α Capricornids||CAP||Jul 15-Aug 15||Aug 1-2||5||20h28m||-10°||3.2m||0.3°||23 km/s|
|Perseids||PER||Jul 17-Aug 24||Aug 12d 19h||60-100||03h16m||58°||5.6m||0.2°||59 km/s|
|κ Cygnids||KCG||Aug 3-25||Aug 18?||3||19h04m||59°||1.0m||0.1°||25 km/s|
|α Aurigids||AUR||Aug 25-Sep 10||Aug 31||6||06h04m||39°||4.3m||-0.1°||66 km/s|
|September ε Perseids||SPE||Sep 5-21||Sep 9||5||03h12m||48°||4.3m||0.1°||64 km/s|
|Oct Camelopardalids||OCT||Oct 5-6||Oct 5d 18-22h?||var.||11h00m||78°||-||-||47 km/s|
|Draconids||DRA||Oct 7-10||Oct 8-9||var.||17h28m||54°||-||-||20 km/s|
|ε Geminids||EGE||Oct 14-27||Oct 18||3||06h50m||27°||4.0m||0.0°||70 km/s|
|Orionids||ORI||Oct 14-31||Oct 21-23||25||06h20m||16°||2.6m||0.1°||66 km/s|
|Southern Taurids||STA||mid Sep - late Nov||see notes||5||see chart||2.9m||0.2°||21 km/s|
|Northern Taurids||NTA||mid Oct - early Dec||see notes||5||see chart||3.6m||0.2°||29 km/s|
|Leonids||LEO||Nov 10-24||Nov 17-18||15||10h08m||22°||2.4m||-0.3°||71 km/s|
|Dec Alpha Draconids||DAD||Dec 4-13||Dec 7-8||1||13h00m||60°||-||-||41 km/s|
|Monocerotids||MON||Dec 5-20||Dec 8||2||06h40m||8°||2.5m||-0.2°||41 km/s|
|Sigma Hydrids||HYD||Dec 3-15||Dec 11||3||08h30m||2°||3.2m||-0.2°||58 km/s|
|Geminids||GEM||Dec 7-16||Dec 14d 06h||110||07h28m||33°||4.0m||-0.1°||35 km/s|
|December Leo Minorids||DLM||Dec 5-Feb 4||Dec 20||5||10h44m||30°||3.5m||-0.4°||64 km/s|
|Coma Berenicids||COM||Dec 12-23||Dec 16||3||11h40m||18°||2.4m||-0.3°||65 km/s|
|Ursids||URS||Dec 17-25||Dec 22-23||10||14h28m||76°||0.0m||-0.4°||33 km/s|
Follow the links below for additional information about the main meteor showers and radiant location charts:
Other Meteor Showers of Note
Tau Herculids This minor meteor shower is associated with the remnants of comet 73P/Schwassmann-Wachmann 3. In most years it produces little or no activity. However, occasionally the Earth will encounter one of the denser filaments of particles within the meteor stream and this can lead to somewhat higher activity. The next likely occasion will be on 2022 May 31 when the Earth is predicted to pass through the centre of a filament left by the comet in 1995. The location of the Tau Herculid radiant does seem to vary from outburst to outburst, but is generally near RA 14h05m, Dec +30 – within the constellation of Bootes, and somewhat distant from Hercules.
Sigma Hydrids This minor shower is active in early to mid-December and only produces low activity rates but, over its two-week activity period, produces a significant overall number of meteors. Peak rates occur around Dec 11th. The radiant is located below the head of Hydra. Note that the radiant doesn’t rise above the horizon until mid-evening and so no Sigma Hydrids will be seen before this time. The best observed rates occur after midnight, when the radiant is climbing higher in the sky. There will be some moonlight interference for the 2017 Sigma Hydrids, with the Last Quarter Moon being located near the Leo-Virgo border during the night of Dec 10-11.
December Leo Minorids and Coma Berenicids: The minor Coma Berenicid shower underwent a degree of confusion in recent times, after IMO video results found apparently identically very swift, mostly faint, meteors radiating from an area about 15° west of where previous visual observations had suggested it should be, as well as from the anticipated radiant. It now seems there may be two minor showers active here, of which the December Leo Minorids is marginally the stronger, and apparently the longer-lasting. Initially thought that both peaked around December 20, the Coma shower is now believed to reach its weak maximum a few days sooner (and from a somewhat different position than earlier indicated). It may be that visual observers will struggle to identify the sources as separate, given previous apparent difficulties in this respect. With these showers only being readily observable late in the night, moonlight will not be a problem in 2017, as New Moon occurs on Dec 18. The December Leo Minorid radiant is usefully observable after 22:30 UT, while the Coma Berenicid radiant area is so placed only after 01h.
Antihelion Source (ANT) Radiant Centre Locations
The use of the “Antihelion Source” relates to the problem of distinguishing between a large number of minor shower radiants that are active around the anti-solar position on the ecliptic throughout the year. With the radiants involved often being close together, it has been virtually impossible for visual observers to reliably assign a given meteor to the correct minor shower. Hence, rather than maintain an unreliable list of minor showers along the ecliptic, the solution has been to assign all such meteors to this “antihelion source”. The only exceptions to this have been those showers that are strong enough tio clearly stand out above the background levels, these being the Delta Aquarids and Alpha Capricornids in the summer and the Taurids in the autumn.
Source is active all year except during STA & NTA; Better ZHRs (3-4) likely in March-April, early & late May & June, and early July; Radiant area is about 30° in RA by 15° in Dec.
|September 15||STA only|
|October 1||STA only|
|October 15||NTA & STA|
|November 1||NTA & STA|
|November 15||NTA & STA|
|December 1||NTA only|