Abstract :
[en] P. Jenniskens, SETI Institute and NASA Ames Research Center, reports the detection of a newly recognized meteor shower with a radiant in Fornax on 2024 July 4, given the provisional name psi-Fornacids (cf. website URL http://cams.seti.org/FDL/ for the date of 2024 July 4). Twenty-eight meteors were triangulated by CAMS New Zealand (coordinated by J. Baggaley, University of Canterbury, and J. Scott, University of Otago), nine by CAMS Australia (H. Devillepoix, Curtin University, and D. Rollinson), one by CAMS South Africa (T. Cooper), and one by CAMS Chile (S. Heathcote, NOIRLAB/Cerro Tololo, and E. Jehin, University of Liege). The triangulated meteors had a magnitude range of -2 to + 3; the shower was active from July 3 to 6 (corresponding to solar longitude 101.9 to 105.3 deg, peaking at 102.9 deg, equinox J2000.0). Meteors radiated from geocentric coordinates R.A. = 44.3 +/- 2.4 deg, Decl. = -38.2 +/- 1.5 deg, with geocentric velocity 51.6 +/- 1.8 km/s (one-standard- deviation dispersion). The sun-centered ecliptic radiant is centered at lambda = 281.4 +/- 0.4, beta = -51.8 +/- 0.2 deg (standard error). Orbital elements are those of a long-period comet meteoroid stream that grazes the earth's orbit with the following median orbital elements (and standard errors): semi-major axis about 27.2 AU, q = 0.9923 +/- 0.0002 AU, e = 0.964 +/- 0.023, i = 92.8 +/- 0.3 deg, Peri. = 342.0 +/- 0.7 deg, and Node = 282.89 +/- 0.15 deg (equinox J2000.0). This is an annual shower with the annual number of orbits measured, starting in 2019: 6, 11, 11, 18, 11, 40. A possible parent body is the poorly observed comet C/1930 L1 (Forbes), with parabolic orbital elements q = 1.153 AU, i = 97.09 deg, Peri. = 320.97 deg, Node = 279.26 deg, and a theoretical shower radiant at R.A. = 44.1 deg, Decl. = -31.8 deg, and geocentric velocity 51.7 km/s centered on solar longitude 99.8 deg (using the method P+ of Neslusan et al. 1998, A.Ap. 331, 411).
