Electronic Telegram No. 5688
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
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Prepared using the Tamkin Foundation Computer Network


2020 BX_14 AND THE ALPHA CAPRICORNIDS METEOR SHOWER COMPLEX
     A. Christou, Armagh Observatory and Planetarium, reports that minor 
planet 2020 BX_14 has an orbit that is very similar to the orbits of comets 
169P/NEAT, P/2003 T12 (SOHO), and P/2024 OC_2 (PANSTARRS), which were
previously linked to the alpha Capricornids meteor shower complex (IAU showers
1, CAP; 115, DCS; and 623, XCS; cf. Brown et al. 2010, Icarus 207, 66; 
Jenniskens et al. 2016, Icarus 266, 331; Sosa and Fernandez 2015, IAU G.A. 29,
2255583 via https://ui.adsabs.harvard.edu/abs/2015IAUGA..2255583S/abstract;
Greaves 2025, eMetN Meteor Journal 10, 27; accessible via website URL 
https://www.emeteornews.net/wp-content/uploads/2024/12/eMetN2025_1.pdf).
Geocentric radiant solutions (equinox J2000.0) using the 2-opposition orbit on 
MPO 894110 with method "A" of Neslusan et al. (1998, A.Ap. 331, 411) as in
Jenniskens et al. (op.cit.) yield solar longitude 123.6 deg, R.A. = 304.7 deg, 
Decl. = -10.3 deg, and geocentric velocity 23.9 km/s at the descending node 
(for CAP and XCS) and solar longitude 305.2 deg, R.A. = 309.0 deg, Decl. =
-28.3 deg, geocentric velocity 24.0 km/s at the ascending node (DCS) for this 
minor planet, in very good agreement with the observed shower orbits (IAU 
Meteor Data Center list of all meteor showers, accessed on 2026 Apr. 8).  A 
slightly smaller solar longitude and slightly higher geocentric velocity than 
is seen with the CAP shower make 2020 BX_14 a particularly good match to the
XCS shower (Southworth-Hawkins orbital similarity criterion value D = 0.045,
vs. 0.087-0.106 for the comets; cf. Southworth and Hawkins 1963, Smithsonian 
Contributions to Astrophysics 7, 261-285).  It is therefore likely that 2020 
BX_14 is a weakly active or extinct comet nucleus that may have originated
from the disintegration of the original parent comet of the complex around 
5k yr ago (Jenniskens and Vaubaillon 2010, A.J. 139, 1822).  No known cometary 
activity has been reported for 2020 BX_14.  Its absolute magnitude H = 20.1 
(MPO 894110) implies a diameter of around 0.6 km for an assumed visible 
geometric albedo of 0.04; it was initially reported by ATLAS/Haleakala on 
2020 Jan. 29 (MPEC 2020-C17), with pre-discovery observations subsequently 
found from its 2016 apparition (MPEC 2024-V198).  The object was not observed 
in 2024 when predicted to reach perihelion on the far side of the sun as 
viewed from the earth.  Re-examination of previous observations of 2020 BX_14 
is encouraged to search for evidence of outgassing from this candidate comet 
nucleus.  Alternatively, the object's next perihelion passage in the second 
half of 2028 offers favorable conditions (e.g., magnitude V = 20.5 and solar
elongation 90 deg on 2028 Aug. 10 when r = 1.07 AU, Delta = 0.35 AU) for 
observational determination of the taxonomic type and for coma/tail searches.


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

                         (C) Copyright 2026 CBAT
2026 May 6                       (CBET 5688)              Daniel W. E. Green