Electronic Telegram No. 5666
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
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Prepared using the Tamkin Foundation Computer Network


DELTA NORMID METEORS 2026
     D. Vida, University of Western Ontario; D. Segon, Croatian Meteor
Network; P. Roggemans, Mechelen, Belgium; J. Wood, Willetton, Australia; J.
Scott, Aarhus University; and W. J. Cooke and A. Vriezelaar, NASA Meteoroid
Environment Office, report an outburst of the delta Normid (DNO) meteor shower
(IAU shower no. 915):  250 delta-Normid meteors were observed by the Global
Meteor Network (GMN) low-light video cameras between 2026 Feb. 18 and 24 (cf.
website URL https://globalmeteornetwork.org/data/).  The shower was
independently observed by cameras in five countries (Australia, Brazil, New
Zealand, United States, and South Africa).  The GMN observed DNO meteors in
2025, but their observed activity was about 10 times lower.  A zenithal
hourly rate in a 1-hour bin around the peak was measured at 60 +/- 4 meteors
per hour, based on 872 single-station meteors observed within that one-hour
period.  The shower had a median geocentric radiant at R.A. = 238.5 deg, Decl.
= -46.0 deg (equinox J2000.0), within a very narrow circle having a standard
deviation of +/- 0.62 deg.  The radiant drift in R.A. was 1.08 deg on the sky
per degree of solar longitude and -0.16 degrees in Decl., both with reference
to the sun at longitude 334.5 deg.  The median sun-centered ecliptic
coordinates were L - L0 = 271.8 deg, beta = -25.2 deg.  The geocentric
velocity was 66.67 +/- 0.06 km/s.  The orbital elements are characteristic of
a Halley-type comet on a retrograde orbit:  q = 0.9851 +/- 0.0021 AU, e =
0.921 +/- 0.086, i = 136.8 +/- 0.9 deg, Peri. = 353.2 +/- 2.0 deg, Node =
154.1 +/- 1.2 deg (equinox J2000.0).  All meteors appeared during in the
solar-longitude interval 329.04-334.74 degrees, with a very sharp peak at
roughly 334.71 degrees that was 0.02 deg wide (duration about 30 minutes). A
plot of co-added GMN radiant locations for the night of 2025 Feb. 22-23 (cf.
website URL https://tinyurl.com/ydbzj6nr) shows a concentration of radiants
near the bottom right of the plot, which is the DNO shower.  A parent-body
search with a "Drummond D" criterion (cf. Drummond 2000, Icarus 146, 453)
returned a potential candidate in comet C/1861 Y1 (Tuttle) with D = 0.13.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2026 CBAT
2026 February 24                 (CBET 5666)              Daniel W. E. Green