Southern δ-Aquariids 12 Ιουλίου - 19 Αυγούστου (27july Max)

[Bi2L]

Southern δ-Aquariids (SDA)

 

Active: July 12 — August 19

Maximum: July 27 (λsol = 125°)

ZHR = 20

Radiant: α = 339° δ = -16°

Radiant drift: see Table 6

vinf = 41 km/s; r = 3.2

TFC: α = 255° to 000° δ = 00° to +15°

choose pairs separated by about 30° in α (β < 40° N)

 

One of the biggest changes brought about in the revamp of the Working List was the removal of the former streams of the Northern δ-Aquariids, and the Northern and Southern ι-Aquariids, all of which proved separately unidentifiable in a series of recent IMO and non-IMO analyses. This greatly simplifies matters for visual observers especially, who often struggled because of the confusion of minor radiants thought present in the Aquarius-Capricornus region during July-August. Like the PAU and ANT, the SDA meteors are often faint, thus are suitable targets for telescopic observing, although enough brighter members exist to make visual and imaging observations worth the effort too, primarily from more southerly sites. Radio work can pick up the SDA as well, and indeed the shower has sometimes given a surprisingly strong radio signature. Careful visual plotting is advised, to help with accurate shower association. The SDA/PAU/ANT/CAP radiants are well above the horizon for much of the night. The moonless maximum may not be quite so sharp as the single date suggested here might imply, perhaps lasting with similar activity from July 27 — 29. Its rates have been suspected of some variability at times too, though not in the more recent investigations.