Abbreviations and observing tables
- α, δ: Coordinates for a shower’s radiant position, usually at maximum. α is right ascension, δ is declination. Radiants drift across the sky each day due to the Earth’s own orbital motion around the Sun, and this must be allowed for using the details in Table 6 (page 23) for nights away from the listed shower maxima.
- r: The population index, a term computed from each shower’s meteor magnitude distribution. r = 2.0 -2.5 is brighter than average, while r above 3.0 is fainter than average.
- λ: Solar longitude, a precise measure of the Earth’s position on its orbit which is not dependent on the vagaries of the calendar. All λ are given for the equinox 2000.0.
- v∞: Atmospheric or apparent meteoric velocity, given in km/s. Velocities range from about 11 km/s (very slow) to 72 km/s (very fast). 40 km/s is roughly medium speed.
- ZHR: Zenithal Hourly Rate, a calculated maximum number of meteors an ideal observer would see in perfectly clear skies with the shower radiant overhead. This figure is given in terms of meteors per hour. Where meteor activity persisted at a high level for less than an hour, or where observing circumstances were very poor, an estimated ZHR (EZHR) is used, which is less accurate than the normal ZHR.
- TFC and PFC: Suggested telescopic and small-camera photographic field centres respectively. β is the observer’s latitude (“<” means “south of” and “>” means “north of”). Pairs of telescopic fields must be observed, alternating about every half hour, so that the positions of radiants can be defined. The exact choice of TFC or PFC depends on the observer’s location and the elevation of the radiant. Note that the TFCs are also useful centres to use for video camera fields as well.
Table 4. Lunar phases for 2006.
| New Moon | First Quarter | Full Moon | Last Quarter |
|---|---|---|---|
| January 6 | January 14 | January 22 | |
| January 29 | February 5 | February 13 | February 21 |
| February 28 | March 6 | March 14 | March 22 |
| March 29 | April 5 | April 13 | April 21 |
| April 27 | May 5 | May 13 | May 20 |
| May 27 | June 3 | June 11 | June 18 |
| June 25 | July 3 | July 11 | July 17 |
| July 25 | August 2 | August 9 | August 16 |
| August 23 | August 31 | September 7 | September 14 |
| September 22 | September 30 | October 7 | October 14 |
| October 22 | October 29 | November 5 | November 12 |
| November 20 | November 28 | December 5 | December 12 |
| December 20 | December 27 |
Table 5. Working list of visual meteor showers
Details in this Table were correct according to the best information
available in April 2005. Contact the IMO‘s Visual Commission for more
information. Maximum dates in parentheses indicate reference dates for the
radiant, not true maxima. Some showers have ZHRs that vary from year to year.
The most recent reliable figure is given here, except for possibly periodic
showers that are noted as “var.” = variable. An asterisk
(“*”) in the “?” column indicates the shower
may have other or additional peak times, noted in the text.
| Shower | Activity | Max Date | ? | ? | ? | v? | r | ZHR |
|---|---|---|---|---|---|---|---|---|
Quadrantids (QUA) |
Jan 01-Jan 05 | Jan 03 | 283° 16 | 230° | +49° | 41 | 2.1 | 120 |
?-Cancrids (DCA) |
Jan 01-Jan 24 | Jan 17 | 297° | 130° | +20° | 28 | 3.0 | 4 |
?-Centaurids (ACE) |
Jan 28-Feb 21 | Feb 08 | 319° 2 | 210° | -59° | 56 | 2.0 | 6 |
?-Leonids (DLE) |
Feb 15-Mar 10 | Feb 24 | 336° | 168° | +16° | 23 | 3.0 | 2 |
?-Normids (GNO) |
Feb 25-Mar 22 | Mar 13 | 353° | 249° | -51° | 56 | 2.4 | 8 |
Virginids (VIR) |
Jan 25-Apr 15 | (Mar 24) | (4° ) | 195° | -04° | 30 | 3.0 | 5 |
Lyrids (LYR) |
Apr 16-Apr 25 | Apr 22 | 32° 32 | 271° | +34° | 49 | 2.1 | 18 |
?-Puppids (PPU) |
Apr 15-Apr 28 | Apr 23 | 33° 5 | 110° | -45° | 18 | 2.0 | var |
?-Aquarids (ETA) |
Apr 19-May 28 | May 06 | 45° 5 | 338° | -01° | 66 | 2.4 | 60 |
Sagittarids (SAG) |
Apr 15-Jul 15 | (May 20) | (59° ) | 247° | -22° | 30 | 2.5 | 5 |
June Bootids (JBO) |
Jun 26-Jul 02 | Jun 27 | 95° 7 | 224° | +48° | 18 | 2.2 | var |
Pegasids (JPE) |
Jul 07-Jul 13 | Jul 09 | 107° 5 | 340° | +15° | 70 | 3.0 | 3 |
Jul Phoenicids (PHE) |
Jul 10-Jul 16 | Jul 13 | 111° | 32° | -48° | 47 | 3.0 | var |
Piscis Austrinids (PAU) |
Jul 15-Aug 10 | Jul 28 | 125° | 341° | -30° | 35 | 3.2 | 5 |
South. ?-Aquarids (SDA) |
Jul 12-Aug 19 | Jul 28 | 125° | 339° | -16° | 41 | 3.2 | 20 |
?-Capricornids (CAP) |
Jul 03-Aug 15 | Jul 30 | 127° | 307° | -10° | 23 | 2.5 | 4 |
South. ?-Aquarids (SIA) |
Jul 25-Aug 15 | Aug 04 | 132° | 334° | -15° | 34 | 2.9 | 2 |
North. ?-Aquarids (NDA) |
Jul 15-Aug 25 | Aug 08 | 136° | 335° | -05° | 42 | 3.4 | 4 |
Perseids (PER)* |
Jul 17-Aug 24 | Aug 12 | 140° 0 | 46° | +58° | 59 | 2.6 | 100 |
?-Cygnids (KCG) |
Aug 03-Aug 25 | Aug 18 | 145° | 286° | +59° | 25 | 3.0 | 3 |
North. ?-Aquarids (NIA) |
Aug 11-Aug 31 | Aug 20 | 147° | 327° | -06° | 31 | 3.2 | 3 |
?-Aurigids (AUR) |
Aug 25-Sep 08 | Sep 01 | 158° 6 | 84° | +42° | 66 | 2.6 | 10 |
?-Aurigids (DAU)* |
Sep 05-Oct 10 | Sep 09 | 166° 7 | 60° | +47° | 64 | 2.9 | 5 |
Piscids (SPI) |
Sep 01-Sep 30 | Sep 20 | 177° | 5° | -01° | 26 | 3.0 | 3 |
Draconids (GIA) |
Oct 06-Oct 10 | Oct 08 | 195° 4 | 262° | +54° | 20 | 2.6 | var |
?-Geminids (EGE) |
Oct 14-Oct 27 | Oct 18 | 205° | 102° | +27° | 70 | 3.0 | 2 |
Orionids (ORI) |
Oct 02-Nov 07 | Oct 21 | 208° | 95° | +16° | 66 | 2.5 | 23 |
Southern Taurids (STA) |
Oct 01-Nov 25 | Nov 05 | 223° | 52° | +13° | 27 | 2.3 | 5 |
Northern Taurids (NTA) |
Oct 01-Nov 25 | Nov 12 | 230° | 58° | +22° | 29 | 2.3 | 5 |
Leonids (LEO) |
Nov 14-Nov 21 | Nov 19 | 235° 27 | 153° | +22° | 71 | 2.5 | 100+ |
?-Monocerotids (AMO) |
Nov 15-Nov 25 | Nov 21 | 239° 32 | 117° | +01° | 65 | 2.4 | var |
?-Orionids (XOR) |
Nov 26-Dec 15 | Dec 02 | 250° | 82° | +23° | 28 | 3.0 | 3 |
Dec Phoenicids (PHO) |
Nov 28-Dec 09 | Dec 06 | 254° 25 | 18° | -53° | 18 | 2.8 | var |
Puppid/Velids (PUP) |
Dec 01-Dec 15 | (Dec 07) | (255° ) | 123° | -45° | 40 | 2.9 | 10 |
Monocerotids (MON) |
Nov 27-Dec 17 | Dec 09 | 257° | 100° | +08° | 42 | 3.0 | 3 |
?-Hydrids (HYD) |
Dec 03-Dec 15 | Dec 12 | 260° | 127° | +02° | 58 | 3.0 | 2 |
Geminids (GEM) |
Dec 07-Dec 17 | Dec 14 | 262° 2 | 112° | +33° | 35 | 2.6 | 120 |
Coma Berenicids (COM) |
Dec 12-Jan 23 | Dec 20 | 268° | 175° | +25° | 65 | 3.0 | 5 |
Ursids (URS) |
Dec 17-Dec 26 | Dec 22 | 270° 7 | 217° | +76° | 33 | 3.0 | 10 |
Table 6. Radiant drift positions during the year in ? and ?
| COM | DCA | QUA | |||||||
| Jan 0 | 186 +20 | 112 +22 | 228 +50 | ||||||
| Jan 5 | 190 +18 | 116 +22 | 231 +49 | ||||||
| Jan 10 | 194 +17 | 121 +21 | |||||||
| Jan 20 | 202 +13 | 130 +19 | ACE | VIR | |||||
| Jan 30 | 200 -57 | 157 +16 | DLE | ||||||
| Feb 10 | 214 -60 | 165 +10 | 155 +20 | GNO | |||||
| Feb 20 | 225 -63 | 172 +6 | 164 +18 | 225 -53 | |||||
| Feb 28 | 178 +3 | 171 +15 | 234 -52 | ||||||
| Mar 10 | 186 0 | 180 +12 | 245 -51 | ||||||
| Mar 20 | 192 -3 | 256 -50 | |||||||
| Mar 30 | 198 -5 | ||||||||
| Apr 10 | SAG | LYR | PPU | 203 -7 | |||||
| Apr 15 | 224 -17 | 263 +34 | 106 -44 | ETA | 205 -8 | ||||
| Apr 20 | 227 -18 | 269 +34 | 109 -45 | 323 -7 | |||||
| Apr 25 | 230 -19 | 274 +34 | 111 -45 | 328 -5 | |||||
| Apr 30 | 233 -19 | 332 -4 | |||||||
| May 5 | 236 -20 | 337 -2 | |||||||
| May 10 | 240 -21 | 341 0 | |||||||
| May 20 | 247 -22 | 350 +5 | |||||||
| May 30 | 256 -23 | ||||||||
| Jun 10 | 265 -23 | ||||||||
| Jun 15 | 270 -23 | ||||||||
| Jun 20 | 275 -23 | JBO | |||||||
| Jun 25 | 280 -23 | 223 +48 | |||||||
| Jun 30 | 284 -23 | 225 +47 | CAP | JPE | |||||
| Jul 5 | 289 -22 | 285 -16 | SDA | 338 +14 | |||||
| Jul 10 | 293 -22 | PHE | 289 -15 | 325 -19 | NDA | 341 +15 | PER | PAU | |
| Jul 15 | 298 -21 | 032 -48 | 294 -14 | 329 -19 | 316 -10 | 012 +51 | 330 -34 | ||
| Jul 20 | 299 -12 | 333 -18 | 319 -9 | SIA | 018 +52 | 334 -33 | |||
| Jul 25 | 303 -11 | 337 -17 | 323 -9 | 322 -17 | 023 +54 | 338 -31 | |||
| Jul 30 | KCG | 308 -10 | 340 -16 | 327 -8 | 328 -16 | 029 +55 | 343 -29 | ||
| Aug 5 | 283 +58 | NIA | 313 -8 | 345 -14 | 332 -6 | 334 -15 | 037 +57 | 348 -27 | |
| Aug 10 | 284 +58 | 317 -7 | 318 -6 | 349 -13 | 335 -5 | 339 -14 | 043 +58 | 352 -26 | |
| Aug 15 | 285 +59 | 322 -7 | 352 -12 | 339 -4 | 345 -13 | 050 +59 | |||
| Aug 20 | 286 +59 | 327 -6 | AUR | 356 -11 | 343 -3 | 057 +59 | |||
| Aug 25 | 288 +60 | 332 -5 | 076 +42 | 347 -2 | 065 +60 | ||||
| Aug 30 | 289 +60 | 337 -5 | 082 +42 | DAU | |||||
| Sep 5 | 088 +42 | 055 +46 | SPI | ||||||
| Sep 10 | 092 +42 | 060 +47 | 357 -5 | ||||||
| Sep 15 | 066 +48 | 001 -3 | |||||||
| Sep 20 | 071 +48 | 005 -1 | |||||||
| Sep 25 | NTA | STA | 077 +49 | 009 0 | |||||
| Sep 30 | 021 +11 | 023 +5 | ORI | 083 +49 | 013 +2 | ||||
| Oct 5 | 025 +12 | 027 +7 | 085 +14 | 089 +49 | GIA | ||||
| Oct 10 | 029 +14 | 031 +8 | 088 +15 | 095 +49 | EGE | 262 +54 | |||
| Oct 15 | 034 +16 | 035 +9 | 091 +15 | 099 +27 | |||||
| Oct 20 | 038 +17 | 039 +11 | 094 +16 | 104 +27 | |||||
| Oct 25 | 043 +18 | 043 +12 | 098 +16 | 109 +27 | |||||
| Oct 30 | 047 +20 | 047 +13 | 101 +16 | ||||||
| Nov 5 | 053 +21 | 052 +14 | 105 +17 | ||||||
| Nov 10 | 058 +22 | 056 +15 | LEO | AMO | |||||
| Nov 15 | 062 +23 | 060 +16 | 150 +23 | 112 +2 | |||||
| Nov 20 | 067 +24 | 064 +16 | XOR | 153 +21 | 116 +1 | ||||
| Nov 25 | 072 +24 | 069 +17 | 075 +23 | 120 0 | MON | PUP | PHO | ||
| Nov 30 | 080 +23 | HYD | 091 +8 | 120 -45 | 014 -52 | ||||
| Dec 5 | COM | GEM | 085 +23 | 122 +3 | 096 +8 | 122 -45 | 018 -53 | ||
| Dec 10 | 169 +27 | 108 +33 | 090 +23 | 126 +2 | 100 +8 | 125 -45 | 022 -53 | ||
| Dec 15 | 173 +26 | 113 +33 | 094 +23 | 130 +1 | URS | 104 +8 | 128 -45 | ||
| Dec 20 | 177 +24 | 118 +32 | 217 +75 |
Table 7. Working list of daytime radio meteor streams
The 50° N and 30° S “Best Observed” columns give the approximate local mean times between
which a four-element antenna at an elevation of 45° receiving a
signal from a 30 kW transmitter 1000 km away should record at least
85% of any suitably positioned radio-reflecting meteor trails for
the appropriate latitudes. Note that this is often heavily dependent on the
compass direction in which the antenna is pointing, however, and applies only to
dates near the shower’s maximum.
| Shower | Activity | Max Date | ? | ? | ? | 50° N | 30° S | Rate |
|---|---|---|---|---|---|---|---|---|
| Cap/Sagittarids | Jan 13-Feb 04 | Feb 01 | 312° 5 | 299° | -15° | 11h-14h | 09h-14h | medium |
| ?-Capricornids | Jan 29-Feb 28 | Feb 13 | 324° 7 | 315° | -24° | 10h-13h | 08h-15h | low |
| Piscids (Apr) | Apr 08-Apr 29 | Apr 20 | 30° 3 | 7° | +07° | 07h-14h | 08h-13h | low |
| ?-Piscids | Apr 24-Apr 24 | Apr 24 | 34° 2 | 11° | +12° | 07h-14h | 08h-13h | low |
| ?-Arietids | Apr 24-May 27 | May 09 | 48° 7 | 44° | +21° | 08h-15h | 10h-14h | low |
| Arietids (May) | May 04-Jun 06 | May 16 | 55° 5 | 37° | +18° | 08h-15h | 09h-13h | low |
| o-Cetids | May 05-Jun 02 | May 20 | 59° 3 | 28° | -04° | 07h-13h | 07h-13h | medium |
| Arietids | May 22-Jul 02 | Jun 07 | 76° 7 | 44° | +24° | 06h-14h | 08h-12h | high |
| ?-Perseids | May 20-Jul 05 | Jun 09 | 78° 6 | 62° | +23° | 07h-15h | 09h-13h | high |
| ?-Taurids | Jun 05-Jul 17 | Jun 28 | 96° 7 | 86° | +19° | 08h-15h | 09h-13h | medium |
| ?-Leonids | Aug 14-Sep 12 | Aug 25 | 152° 2 | 155° | +20° | 08h-16h | 10h-14h | low |
| Sextantids* | Sep 09-Oct 09 | Sep 27 | 184° 3 | 152° | 00° | 06h-12h | 06h-13h | medium |
Useful addresses
For more information on observing techniques, and when submitting results,
please contact the appropriate IMO Commission Director