Alpha Pegasids

History

The Alpha Pegasids were discovered in 1959, while Richard E. McCrosky and Annette Posen were examining the orbits of meteors photographed during the Harvard Meteor Project of 1952-1954. Three meteors were found, all of which had been photographed on November 12, 1952 (the date had been incorrectly published as November 11). McCrosky and Posen referred to this stream as the "Mu Pegasids" and gave the average radiant as α=340°, δ=+23°. The orbit was given as follows:

ωΩiqea
199.4229.78.30.9650.7784.35

McCrosky and Posen suggested an association with the lost periodic comet Blanpain (1819 IV), based on the similarity of the longitude of perihelion. They said the "comet was subject to repeated perturbations by Jupiter, so it is not unreasonable that the nodes of the orbit of the meteor stream should be the reverse of those of the original comet orbit..." The orbit of the comet was as follows:

ωΩiqea
350.177.49.10.8920.6992.96

In 1971 Bertil-Anders Lindblad conducted a computerized stream search using 2401 photographic orbits detected during the Harvard Meteor Project. In addition to the three meteors originally detected by McCrosky and Posen, two additional meteors were added: one from November 12, 1952, and one from October 29, 1953. The five meteors revealed a duration of October 29-November 12 and an average radiant of α=344°, δ=+19°. The following orbit was revealed.

ωΩiqea
200.2227.06.80.9660.7183.512

The strongest support for this stream's existence obviously comes from the photographic data and the suggestion of a link to comet Blanpain. On the other hand, since four of the five photographic meteors were detected on November 12, 1952, Lindblad suggested "caution should perhaps be exercised" when considering this stream as an annual shower producer. These words have taken on a stronger meaning to the Author as he attempted to locate visual observations of this shower. Although the very first observation of this radiant seems to have been made by R. de Kovesligethy (Hungary) on November 9, 1885, when five meteors were plotted from RA=344 deg, DEC=+19 deg, no trace of the radiant is present among over 6000 American Meteor Society radiants, made during 1900-1984 and over 5400 German observations made during 1908-1938 (H1948).

In recent years a negative report came from N. W. McLeod, III (Florida), who observed only one possible meteor from this stream during nearly 26 hours of observation between November 4 and 17, 1978. On the other hand, a positive report came from members of the Western Australia Meteor Section, who observed a maximum ZHR of 2.20+/-0.12 from α=336°, δ=+19° during November 1-2, 1980.