Electronic Telegram No. 5613
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


NEW METEOR SHOWER M2025-S2 IN HYDRUS
     D. Vida, University of Western Ontario, Canada; D. Segon, Croatian Meteor
Network; and P. Roggemans, Mechelen, Belgium, report an outburst of meteors
with a radiant in Hydrus.  One-hundred-thirty-two relatied meteors were
observed by the Global Meteor Network (GMN) low-light video cameras between
2025 Sept. 8 and 26 (cf. website URL https://globalmeteornetwork.org/data/).
The shower was independently observed by cameras in five countries in the
southern hemisphere (Australia, Brazil, Chile, New Zealand, South Africa).
The shower had a median geocentric radiant with coordinates R.A. = 32.19 deg,
Decl. = -66.53 deg, within a wide circle with a standard deviation of +/- 2.8
deg (equinox J2000.0).  The radiant drift in R.A. is 1.09 deg on the sky per
degree of solar longitude and 0.27 in Decl., both with reference to the sun at
longitude 177.0 degrees.  The median sun-centered ecliptic coordinates were
L - L0 = +156.04 deg, beta = -67.81 deg.  The geocentric velocity was 20.63
+/- 0.10 km/s.  The orbital elements are characteristic of a Jupiter-family
comet:  q = 0.956 +/- 0.008 AU, e = 0.705 +/- 0.045, i =  29.8 +/- 2.0 deg,
Peri. = 27.5 +/- 2.5 deg, Node = 355.0 +/- 2.0 deg (equinox J2000.0).  All
of these related meteors appeared during the solar-longitude interval 166.8-
182.6 degrees, with a peak at roughly 177 degrees.  The shower is still
ongoing as of Sept. 26.  A plot of co-added GMN radiant locations for Sept.
2025 (cf. website URL https://tinyurl.com/4t5k5c63) shows a concentration of
radiants near the bottom right of the plot.  A parent-body search with a
"Drummond D" criterion (cf. Drummon 2000, Icarus 146, 453) returned potential
minor-planet candidates with a value of D < 0.1:  D = 0.087 for 1994 RB, and
D = 0.0.94 for 2022 SJ_48.  The shower has received the working designation
M2025-S2 from the IAU Meteor Data Center.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2025 CBAT
2025 September 27                (CBET 5613)              Daniel W. E. Green