Delta Pavonids

The discovery of the Delta Pavonids is attributed to M. Buhagiar (Perth, West Australia). During the period of 1969-1980, he succeeded in observing this shower in six different years. The duration of activity was determined as April 3-8, while the date of maximum was established as April 6. The average radiant position was α=303°, δ=-63°. The hourly rate was described as variable, but did reach a high of 10. Buhagiar suggested an association with comet Grigg-Mellish. The activity curve begins with a slow rise to maximum, which occurs at a solar longitude of 16.5°, and then rapidly declines.

The variability of the activity from this shower is best evidenced by observations made by the Western Australia Meteor Section (WAMS) in 1980 and 1986. According to J. Wood (director of the WAMS) the maximum ZHR reached 1.88±0.19 on April 5, 1980. The duration was given as April 4-8, while the average radiant position was given as α=305°, δ=-65°. During 1987, 35 members of the WAMS observed for 369 man-hours during late March and early April. The highest ZHR came on March 29/30, when rates were 7.3. The next highest rates were 5.0 on March 21/22 and 4.7 on April 7/8. The meteors possessed an average magnitude of 3.12, while 12.9% left trains.

Comet Grigg-Mellish (1907 II) was once believed to possess a period of 164 years, but recent investigations by B. G. Marsden (Smithsonian Astrophysical Observatory, Massachusetts) makes the short-period nature of this comet "highly improbable." The orbit is currently given as parabolic.