IMO Meteor Shower Calendar 2004

The year sees two of the "big three" major shower peaks - the Perseids and Geminids - mostly or entirely free from moonlight interference, but the third, the Quadrantids, are badly moonlit, along with the alpha-Centaurids, eta-Aquarids, and Southern delta-Aquarids. Other more active sources like the Lyrids, Orionids and Leonids, as well as many minor showers in the second half of the year, plus several uncertain sources such as the pi-Puppids and June Lyrids, enjoy often moonless skies. What the June Bootids may do in 2004 needs checking too.

Do not forget that monitoring of meteor activity should ideally be carried on throughout the rest of the year, however! We appreciate that this is not practical for many observers, and this Calendar was devised as a means of helping observers deal with reality by highlighting times when a particular effort may most usefully be employed. Although we include timing predictions for all the more active night-time and daytime shower maxima, based on the best available data, please note that in many cases, such maxima are not known more precisely than to the nearest 1° of solar longitude (even less accurately for the daytime radio showers, which have only recently begun to receive regular attention again). In addition, variations in individual showers from year to year mean past returns are at best only a guide as to when even major shower peaks can be expected, plus as some showers are known to show particle mass-sorting within their meteoroid streams, the radio, telescopic, video, visual and photographic meteor maxima may occur at different times from one another, and not necessarily just in these showers. The majority of data available are for visual shower maxima, so this must be borne in mind when employing other observing techniques.