1990/01/01 by J. Crovisier, D. Despois, CROVISIER, J +21
Earth and Planetary Sciences · Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Astronomy #Geophysics and Gravity Measurements #Solar and Space Plasma Dynamics
paper · doi:10.7275/2628
openalex publication_date 1990/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
The J(1-0) lines of HCN at 89 GHz were searched for in Comet Wilson 1987 VII, with the FCRAO, the SEST and the IRAM radio telescopes between February and June 1987. There was no firm detection, but significant upper limits were obtained, which put severe constraints on the HCN production rate in that comet. A direct comparison with the observations of P/Halley suggests that the HCN abundance relative to water might be smaller in Comet Wilson by at least a factor of two. The J(1-0) and J(3-2) lines of HCN at 89 and 266 GHz were searched for in Comet Machholz 1988 XV when it was close to perihelion at 0.17 AU from the sun. There was no detection. At that moment, the comet was probably no longer active.