A 2022 τ -Herculid meteor cluster from an airborne experiment: automated detection, characterization, and consequences for meteoroids

• Published in: Astronomy and astrophysics (Berlin) Vol. 670; p. A86
• Main Authors: Vaubaillon, J., Loir, C., Ciocan, C., Kandeepan, M., Millet, M., Cassagne, A., Lacassagne, L., Da Fonseca, P., Zander, F., Buttsworth, D., Loehle, S., Toth, J., Gray, S., Moingeon, A., Rambaux, N.
• Format: Journal Article
• Language: English
• Published: EDP Sciences 01.02.2023
• Subjects: Astrophysics; Computer Science; Computer Vision and Pattern Recognition; Earth and Planetary Astrophysics; Embedded Systems; Physics; meteoroids; Comets: general; method: data analysis
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361/202244993

Context . The existence of meteor clusters has long since been a subject of speculation and so far only seven events have been reported, among which two involve less than five meteors, and three were seen during the Leonid storms. Aims . The 1995 outburst of Comet 73P/Schwassmann-Wachmann was predicted to result in a meteor shower in May 2022. We detected the shower, proved this to be the result of this outburst, and detected another meteor cluster during the same observation mission. Methods . The τ -Herculids meteor shower outburst on 31 May 2022 was continuously monitored for 4 h during an airborne campaign. The video data were analyzed using a recently developed computer-vision processing chain for meteor real-time detection. Results . We report and characterize the detection of a meteor cluster involving 38 fragments, detected at 06:48 UT for a total duration of 11.3 s. The derived cumulative size frequency distribution index is relatively shallow: s = 3.1. Our open-source computer-vision processing chain (named FMDT) detects 100% of the meteors that a human eye is able to detect in the video. Classical automated motion detection assuming a static camera was not suitable for the stabilized camera setup because of residual motion. Conclusions . From all reported meteor clusters, we crudely estimate their occurrence to be less than one per million observed meteors. Low heliocentric distance enhances the probability of such meteoroid self-disruption in the interplanetary space.