* * * * * C/2021 Y1 (ATLAS) * * * * *

Year Mn Day    MM  Mag Ref Scope Pwr coma  DC tail p.a. Obs  Site
2023  3 18.42   M 14.6 AQ  40.0L 182  0.9  4/           WYA  Walcha, NSW
(Poor seeing. Diffuse with opaque centre.)
2023  3 16.40   M 14.6 AQ  40.0L 182  1.2  6            WYA  Walcha, NSW
(Diffuse, small opaque centre, pseudo-nucleus visible in good seeing.)
2023  3 15.40   M 14.6 AQ  40.0L 182  0.7  5/           WYA  Walcha, NSW
(Small well condensed centre, transparent outer coma.)
2023  2 16.43   M 15.0 AQ  40.0L 182  0.6  5/           WYA  Walcha, NSW
(Small and diffuse with stellar pseudo-nucleus sometimes visible. Close to mag 12.3 star but resolvable.)
2022 12 26.53   M 14.2 AQ  40.0L 108  0.6  6            WYA  Walcha, NSW
(Stellar pseudo-nucleus visible, semi-opaque coma.)
2022 12 20.48   M 14.2 AQ  40.0L 108  0.8  6            WYA  Walcha, NSW
(Stellar pseudo-nucleus visible, opaque centre, semi-transparent outer coma.)
2022 11 25.64   M 14.7 AQ  40.0L 261  0.4  6            WYA  Walcha, NSW
(Close to star. Stellar pseudo-nucleus visible.)
2022 11 23.50   M 13.6 AQ  40.0L 182  0.5  6            WYA  Walcha, NSW
(Opaque inner coma, faint stellar pseudo-nucleus visible in good seeing. Dims in Swan Band filter. Bright star in field.)