2025/12/26 by Dongyue Jiang, Lei Qian, Jiang, Dongyue +31
Physics and Astronomy · #Astro and Planetary Science #Astrophysics of Galaxies (astro-ph.GA) #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Planetary Science and Exploration #Stellar, planetary, and galactic studies
paper · doi:10.48550/arxiv.2512.21969
openalex publication_date 2025/12/26 · openalex created_date 2025/12/30 · openalex updated_date 2026/07/28
We observed comet C/2025 A6 with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) equipped with the ultra-wideband receiver from 2025 October 23 to November 8, and it was the first detection for this comet with FAST.Through trapezoidal fitting of the OH line profiles, we derived the expansion velocities of the water which showed an increase from 1.5±0.3 km s-1 at the heliocentric distance of 0.65 AU to 3.0±0.9 km s-1 at 0.54 AU. Based on these results, we estimated the OH production rates of C/2025 A6 for October 23, October 26, November 4 and November 5 which were (1.0±0.1)×1029, (1.2±0.1)×1029, (1.4±0.3)×1029, and (1.5±0.4)×1029 s-1 respectively. The results show a significant upward trend.