Recent Comet Brightness Estimates

4P/Faye
Total-magnitude and coma-diameter estimates:
2021 Nov. 13.72, 11.6, 1.9' (C. Wyatt, 0.4-m Newtonian reflector)
2021 Nov. 13.09, 11.0, 7' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.68-deg tail in p.a. 278)
2021 Nov. 11.17, 11.0, 3' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 11.07, 11.9, 2.6' (P. Dekelver, 0.3-m Newtonian reflector; 11.3' tail in p.a. 280)
2021 Nov. 11.07, 10.9, 8.2' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.31-deg tail in p.a. 278)
2021 Nov. 10.19, 10.3, 2.8' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector)
2021 Nov. 10.16, 11.0, 2' (G. Scheerle, 0.235-m Schmidt-Cassegrain)
2021 Nov. 10.12, 11.2, 5.6' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 10.11, 11.4, 3.95' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 10.11, 11.5, 2.8' (P. Dekelver, 0.3-m Newtonian reflector; 13.4' tail in p.a. 278)
2021 Nov. 10.10, 11.3, 1.7' (M. Meyer, 0.254-m Newtonian reflector)
2021 Nov. 10.00, 11.8, 1.2' (M. Filipek, 0.25-m Newtonian reflector)
2021 Nov. 09.22, 11.4, 4.14' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 09.03, 11.8, 2.8' (P. Dekelver, 0.3-m Newtonian reflector; 17.3' tail in p.a. 277)
2021 Nov. 06.97, 11.7, 1' (M. KwintaLocation: Glanów; , 0.25-m Newtonian reflector)
2021 Nov. 06.33, 12.2, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 06.03, 11.6, 4' (P. Dekelver, 0.3-m Newtonian reflector; 17.5' tail in p.a. 276)
2021 Nov. 05.36, 10.6, 2' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 05.10, 11.6, 3' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 05.09, 11.2, 3' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 04.33, 12.1, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 04.14, 11.3, 2' (C. LabordenaLocation: Culla; , 0.2-m Schmidt-Cassegrain)
2021 Nov. 04.10, 11.0, 6.2' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.72-deg tail in p.a. 276)
2021 Nov. 04.04, 11.8, 2.82' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 02.32, 12.1, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 01.12, 11.7, 3.2' (P. Dekelver, 0.3-m Newtonian reflector; 11.8' tail in p.a. 279)
2021 Oct. 31.95, 11.8, 1.2' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector)
2021 Oct. 30.97, 11.7, 1.2' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector)
2021 Oct. 30.03, 10.5, 9.7' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.36-deg tail in p.a. 275)
2021 Oct. 29.07, 11.3, 4' (P. Dekelver, 0.3-m Newtonian reflector; 14.5' tail in p.a. 278)

6P/dArrest
Total-magnitude and coma-diameter estimates:
2021 Nov. 27.98, 10.6, 3' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 07.98, 10.1, 4' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 06.83, 9.9, 15' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.6' tail in p.a. 267)
2021 Nov. 05.97, 10.2, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 05.02, 10.1, 4' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 04.96, 10.2, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 03.95, 10.3, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.96, 10.2, 4' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 02.93, 10.4, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 01.92, 10.4, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)

7P/Pons-Winnecke
Total-magnitude and coma-diameter estimates:
2021 Nov. 06.87, 14.8, 4' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 1.1' tail in p.a. 341)

8P/Tuttle
Total-magnitude and coma-diameter estimates:
2021 Nov. 13.71, 10.4, 3.5' (C. Wyatt, 0.4-m Newtonian reflector)
2021 Nov. 06.32, 11.0, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 04.32, 10.8, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.32, 10.5, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 01.12, 11.0, 2' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

15P/Finlay
Total-magnitude and coma-diameter estimates:
2021 Nov. 10.18, 13.6, 0.8' (G. Scheerle, 0.235-m Schmidt-Cassegrain)
2021 Nov. 05.16, 17.6, 0.6' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

17P/Holmes
Total-magnitude and coma-diameter estimates:
2021 Nov. 05.05, 18.1, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

19P/Borrelly
Total-magnitude and coma-diameter estimates:
2021 Nov. 27.96, 11.0, 2.5' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 21.96, 11.1, 2' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 13.03, 10.7, 13' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.9' tail in p.a. 224)
2021 Nov. 06.89, 11.0, 12' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.05-deg tail in p.a. 45)
2021 Nov. 05.99, 11.4, 2.5' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 04.97, 11.7, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 03.98, 11.6, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.98, 11.6, 2.5' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.12, 11.6, 1.5' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 01.99, 11.7, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 01.78, 11.0, 12' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.07-deg tail in p.a. 44)

28P/Neujmin
Total-magnitude and coma-diameter estimates:
2021 Nov. 08.10, 17.0, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

29P/Schwassmann-Wachmann
Total-magnitude and coma-diameter estimates:
2021 Nov. 26.93, 10.4, 6' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 24.95, 10.3, 5.8' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 24.87, 11.2, 4.32' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 23.89, 10.2, 5.6' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 22.95, 10.3, 5.3' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 21.79, 9.8, 4' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 17.83, 12.0, 2' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 16.13, 10.8, 5' (P. Guzik, 25x100 binoculars)
2021 Nov. 15.22, 9.9, 7.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 13.90, 10.4, 4.89' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 13.69, 11.0, 2.9' (C. Wyatt, 0.4-m Newtonian reflector)
2021 Nov. 13.13, 10.1, 6.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 13.05, 10.8, 6.9' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector)
2021 Nov. 12.85, 10.9, 3.57' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 11.94, 10.5, 4.89' (N. JamesLocation: 970; , 0.28-m Schmidt-Cassegrain)
2021 Nov. 11.90, 10.4, 7.2' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 11.09, 10.1, 5' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 11.05, 10.8, 5' (P. Guzik, 25x100 binoculars)
2021 Nov. 10.96, 10.4, 6.8' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 10.94, 10.7, 9.6' (S. FritscheLocation: Koeditz; , 0.1-m refractor)
2021 Nov. 10.17, 10.6, 2.2' (G. Scheerle, 0.235-m Schmidt-Cassegrain)
2021 Nov. 10.12, 10.8, 4.5' (M. Meyer, 0.254-m Newtonian reflector)
2021 Nov. 10.10, 10.1, 6.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 09.99, 11.2, 1.4' (G. Scheerle, 0.235-m Schmidt-Cassegrain)
2021 Nov. 09.92, 10.8, 3' (M. Filipek, 0.25-m Newtonian reflector)
2021 Nov. 09.92, 10.8, 4' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector)
2021 Nov. 09.89, 10.7, 7.8' (S. FritscheLocation: Koeditz; , 0.1-m refractor)
2021 Nov. 09.87, 10.5, 3.4' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 09.17, 11.3, 5.83' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.3-m Newtonian reflector)
2021 Nov. 08.91, 10.4, 6' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 08.83, 10.0, 5' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 08.08, 10.2, 5.8' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 08.04, 10.5, 3.5' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 06.97, 10.6, 5' (P. Guzik, 25x100 binoculars)
2021 Nov. 06.90, 10.8, 3' (M. KwintaLocation: Glanów; , 0.25-m Newtonian reflector)
2021 Nov. 06.90, 11.1, 3' (M. Filipek, 0.25-m Newtonian reflector)
2021 Nov. 05.98, 10.5, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 05.97, 10.5, 5' (P. GuzikLocation: Niżna Łąka, Poland; , 25x100 binoculars)
2021 Nov. 05.92, 10.2, 2.3' (M. BielyLocation: Czech Republic, Brno; , 20x80 binoculars)
2021 Nov. 05.91, 10.6, 6.8' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 05.42, 10.7, 3' (K. WierzchosLocation: Oro Valley, AZ; , 0.317-m Newtonian reflector)
2021 Nov. 05.11, 10.0, 4' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 05.10, 10.2, 5' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 05.04, 10.5, 6' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 05.01, 10.2, 5.3' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 04.97, 10.7, 2.9' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 04.94, 10.7, 3.57' (N. JamesLocation: 970; , 0.28-m Schmidt-Cassegrain)
2021 Nov. 04.50, 10.7, 3' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 04.30, 10.9, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 04.05, 10.8, 3' (C. LabordenaLocation: Culla; , 0.2-m Schmidt-Cassegrain)
2021 Nov. 04.01, 10.8, 5.9' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 1.1' tail in p.a. 270)
2021 Nov. 04.00, 10.3, 4.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 03.97, 10.4, 4.7' (D. BuczynskiLocation: Tarbatness MPC COde I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 02.97, 10.8, 2.8' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 02.92, 10.8, 3.38' (N. JamesLocation: 970; , 0.28-m Schmidt-Cassegrain)
2021 Nov. 02.29, 10.7, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.13, 10.6, 2.9' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector)
2021 Nov. 02.06, 10.5, 6' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 01.97, 10.8, 3.2' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 01.89, 10.8, 3' (A. ScholtenLocation: Eerbeek; , 0.356-m Schmidt-Cassegrain)
2021 Nov. 01.85, 11.4, 1.8' (C. HarderLocation: Jeersdorf, f; , 0.531-m Newtonian reflector)
2021 Nov. 01.80, 10.3, 3' (M. Meyer, 0.254-m Newtonian reflector)
2021 Nov. 01.04, 10.7, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 01.02, 10.4, 4' (P. GuzikLocation: Lipowiec, Poland; , 25x100 binoculars)
2021 Nov. 01.02, 10.4, 6' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Oct. 31.98, 9.9, 2.8' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Oct. 31.94, 10.8, 2' (M. Filipek, 0.33-m Newtonian reflector)
2021 Oct. 31.88, 10.4, 3.5' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector)
2021 Oct. 31.30, 10.5, 3.7' (G. van BuitenenLocation: Mayhill, New Mexico (H06); , 0.43-m Ritchey-Chretien)
2021 Oct. 31.00, 10.7, 3.2' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Oct. 30.99, 10.4, 4' (P. Guzik, 25x100 binoculars)
2021 Oct. 30.97, 10.7, 1.1' (M. ParadowskiLocation: Lublin, Poland; , 0.203-m Newtonian reflector)
2021 Oct. 30.93, 10.7, 3' (V. BespalovLocation: Moscow region, Ruza; , 0.2-m Newtonian reflector)
2021 Oct. 30.93, 10.7, 4.5' (M. ParadowskiLocation: Lublin; , 0.054-m refractor)
2021 Oct. 30.87, 10.4, 3.5' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector)
2021 Oct. 29.96, 10.4, 3.76' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Oct. 29.95, 10.8, 7.9' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.05-deg tail in p.a. 267)
2021 Oct. 29.91, 10.9, 3' (N. JamesLocation: 970; , 0.28-m Schmidt-Cassegrain)
2021 Oct. 29.91, 10.5, 2.4' (M. Kwinta, 0.19-m Newtonian reflector)
2021 Oct. 29.81, 10.7, 1.3' (C. HarderLocation: Jeersdorf, f; , 0.298-m Newtonian reflector)
2021 Oct. 29.10, 10.5, 3.7' (G. van BuitenenLocation: Dordrecht, NL (G06); , 0.203-m Ritchey-Chretien)

57P/du Toit-Neujmin-Delporte
Total-magnitude and coma-diameter estimates:
2021 Nov. 24.70, 11.7, 3.4' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.07-deg tail in p.a. 77)
2021 Nov. 09.71, 11.0, 0.5' (U. Pilz, 0.32-m Newtonian reflector)
2021 Nov. 07.97, 11.8, 1.5' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 03.99, 12.8, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.99, 12.9, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 01.98, 12.8, 1' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Oct. 31.72, 12.1, 2.1' (M. Paradowski, 0.034-m reflector)

67P/Churyumov-Gerasimenko
Total-magnitude and coma-diameter estimates:
2021 Nov. 28.29, 9.0, 5' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 21.99, 8.7, 4' (P. Dekelver, 0.3-m Newtonian reflector; 23.2' tail in p.a. 288)
2021 Nov. 16.49, 8.5, 16.5' (J. ChamboLocation: Mayhill, New Mexico; , 0.106-m refractor; 2.0-deg tail in p.a. 285)
2021 Nov. 16.18, 8.9, 3.9' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 16.12, 8.9, 5' (P. Guzik, 25x100 binoculars; 0.3-deg tail in p.a. 275)
2021 Nov. 16.12, 8.7, 6' (P. Guzik, 10x50 binoculars)
2021 Nov. 15.28, 8.9, 6' (M. Goiato, 20x100 binoculars)
2021 Nov. 15.27, 9.0, 5' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 13.67, 9.1, 3.3' (C. Wyatt, 0.4-m Newtonian reflector; 12.0' tail in p.a. 275)
2021 Nov. 13.17, 8.7, 13.3' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 13.10, 8.3, 26' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 1.29-deg tail in p.a. 283)
2021 Nov. 12.18, 8.6, 2.9' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain; 2.4' tail in p.a. 277)
2021 Nov. 11.98, 9.0, 3.9' (A. KammererLocation: Teufelsmuehle (Black Forest), Germany; , 0.203-m Schmidt-Cassegrain)
2021 Nov. 11.11, 9.2, 4' (J. Gonzalez Suarez, 25x100 binoculars)
2021 Nov. 11.10, 9.8, 4' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain; 0.25-deg tail in p.a. 280)
2021 Nov. 11.04, 9.6, 4.8' (P. Dekelver, 0.3-m Newtonian reflector; 22.8' tail in p.a. 284)
2021 Nov. 11.03, 8.9, 5' (P. Guzik, 10x50 binoculars)
2021 Nov. 11.03, 8.1, 30' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.95-deg tail in p.a. 282)
2021 Nov. 10.18, 8.7, 13.2' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 10.15, 8.6, 3.5' (G. Scheerle, 0.235-m Schmidt-Cassegrain)
2021 Nov. 10.14, 9.3, 4' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 10.08, 8.9, 4' (M. Meyer, 0.254-m Newtonian reflector)
2021 Nov. 10.08, 9.5, 6' (P. Dekelver, 0.3-m Newtonian reflector; 22.6' tail in p.a. 283)
2021 Nov. 10.07, 9.4, 6' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 09.94, 9.5, 2' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector; 10.0' tail in p.a. 280)
2021 Nov. 09.94, 9.4, 2' (M. Filipek, 0.25-m Newtonian reflector)
2021 Nov. 09.20, 9.5, 6' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 09.00, 9.6, 4' (P. Dekelver, 0.3-m Newtonian reflector; 22.7' tail in p.a. 283)
2021 Nov. 08.85, 9.5, 5' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 08.15, 9.5, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 08.02, 9.3, 3.1' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 07.45, 8.9, 10' (J. ChamboLocation: Mayhill, New Mexico; , 0.431-m Ritchey-Chretien; 37.0' tail in p.a. 281)
2021 Nov. 07.21, 9.6, 1.8' (M. DeconinckLocation: Aquarellia Observatory; , 0.25-m Cassegrain reflector; 2.2' tail in p.a. 260)
2021 Nov. 07.11, 8.8, 7.5' (M. ParadowskiLocation: Lublin; , 0.054-m refractor)
2021 Nov. 07.10, 9.0, 7.5' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 0.25-deg tail in p.a. 280)
2021 Nov. 07.10, 9.1, 6' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 0.25-deg tail in p.a. 280)
2021 Nov. 07.10, 9.2, 5.2' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 0.25-deg tail in p.a. 280)
2021 Nov. 07.09, 9.3, 5.2' (M. ParadowskiLocation: Lublin; , 0.054-m refractor)
2021 Nov. 07.01, 10.0, 2.3' (V. DíazLocation: La Romana, Alicante, España; , 0.2-m Newtonian reflector)
2021 Nov. 06.98, 9.1, 6' (P. Guzik, 10x50 binoculars)
2021 Nov. 06.95, 10.0, 2' (M. Filipek, 0.25-m Newtonian reflector; 0.05-deg tail in p.a. 280)
2021 Nov. 06.94, 9.6, 3' (M. KwintaLocation: Glanów; , 0.25-m Newtonian reflector; 6.0' tail in p.a. 275)
2021 Nov. 05.99, 9.5, 6' (P. Dekelver, 0.3-m Newtonian reflector; 22.9' tail in p.a. 285)
2021 Nov. 05.96, 9.0, 6' (P. GuzikLocation: Niżna Łąka, Poland; , 10x50 binoculars)
2021 Nov. 05.96, 9.5, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 05.93, 9.5, 3' (M. BielyLocation: Czech Republic, Brno; , 20x80 binoculars)
2021 Nov. 05.89, 9.5, 2' (T. CsorgeiLocation: Blahová; , 0.28-m Schmidt-Cassegrain)
2021 Nov. 05.35, 9.0, 4' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 05.25, 9.6, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 05.21, 9.9, 4' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain; 0.15-deg tail in p.a. 280)
2021 Nov. 05.12, 9.5, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 05.12, 9.5, 6' (P. Dekelver, 0.3-m Newtonian reflector; 22.6' tail in p.a. 282)
2021 Nov. 05.12, 8.9, 11.8' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 04.96, 9.1, 3.4' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 04.22, 9.8, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 04.16, 9.0, 5.64' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 04.11, 8.6, 20' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 1.51-deg tail in p.a. 278)
2021 Nov. 04.10, 9.5, 3' (C. LabordenaLocation: Culla; , 0.2-m Schmidt-Cassegrain)
2021 Nov. 03.21, 9.8, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 03.19, 9.6, 5.45' (N. JamesLocation: 970; , 0.28-m Schmidt-Cassegrain)
2021 Nov. 02.99, 9.0, 3.2' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain; 4.0' tail in p.a. 270)
2021 Nov. 02.30, 9.9, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.25, 9.5, 3' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 02.11, 9.2, 2.3' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector; 11.0' tail in p.a. 280)
2021 Nov. 01.99, 9.6, 3.4' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain; 3.2' tail in p.a. 269)
2021 Nov. 01.10, 9.6, 6' (P. Dekelver, 0.3-m Newtonian reflector; 22.0' tail in p.a. 277)
2021 Nov. 01.07, 9.4, 5' (P. GuzikLocation: Niżna Łąka, Poland; , 25x100 binoculars)
2021 Nov. 01.05, 9.3, 4' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 01.00, 8.8, 4' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Oct. 31.94, 9.4, 3' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector; 7.0' tail in p.a. 280)
2021 Oct. 31.92, 9.4, 3' (M. Filipek, 25x100 binoculars)
2021 Oct. 31.05, 9.2, 5' (M. ParadowskiLocation: Lublin, Poland; , 0.203-m Newtonian reflector)
2021 Oct. 31.02, 9.6, 3.7' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Oct. 30.97, 9.3, 5' (P. Guzik, 25x100 binoculars)
2021 Oct. 30.94, 9.5, 3' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector; 8.0' tail in p.a. 280)
2021 Oct. 30.08, 8.8, 17' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.25-deg tail in p.a. 278)
2021 Oct. 29.97, 9.7, 1.8' (W. Kutschera, 0.25-m Newtonian reflector; 0.75-deg tail)
2021 Oct. 29.05, 9.6, 6' (P. Dekelver, 0.3-m Newtonian reflector; 22.1' tail in p.a. 277)

81P/Wild
Total-magnitude and coma-diameter estimates:
2021 Nov. 08.05, 19.0, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

104P/Kowal
Total-magnitude and coma-diameter estimates:
2021 Oct. 31.75, 17.2, 0.2' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

106P/Schuster
Total-magnitude and coma-diameter estimates:
2021 Nov. 10.13, 17.9, 0.38' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)

108P/Ciffreo
Total-magnitude and coma-diameter estimates:
2021 Nov. 21.81, 14.6, 1' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 10.14, 14.0, 3' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 10.09, 14.7, 1.5' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 08.13, 14.7, 1.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

110P/Hartley
Total-magnitude and coma-diameter estimates:
2021 Nov. 13.19, 15.3, 1.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 11.11, 15.6, 1.2' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 1.8' tail in p.a. 286)
2021 Nov. 10.20, 15.9, 0.8' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 05.14, 16.4, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

116P/Wild
Total-magnitude and coma-diameter estimates:
2021 Nov. 05.18, 17.6, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 01.06, 17.2, 0.1' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

120P/Mueller
Total-magnitude and coma-diameter estimates:
2021 Nov. 02.08, 20.5, -- (G. PappaLocation: Namibia (remote control); , 0.5-m Cassegrain reflector)

132P/Helin-Roman-Alu
Total-magnitude and coma-diameter estimates:
2021 Nov. 24.97, 15.3, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 21.80, 13.9, 2' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 11.02, 11.9, 3' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 09.82, 13.9, 2.9' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 1.6' tail in p.a. 45)
2021 Nov. 08.85, 13.6, 0.8' (G. Scheerle, 0.235-m Schmidt-Cassegrain)
2021 Nov. 08.84, 13.6, 1.5' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 04.99, 13.9, 1.3' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 01.84, 13.9, 2.3' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.9' tail in p.a. 40)
2021 Nov. 01.81, 14.5, 0.5' (C. HarderLocation: Jeersdorf, f; , 0.531-m Newtonian reflector)
2021 Oct. 30.87, 14.2, 1.5' (M. ParadowskiLocation: Lublin; , 0.054-m reflector)
2021 Oct. 29.91, 14.1, 1.9' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.8' tail in p.a. 71)

193P/LINEAR-NEAT
Total-magnitude and coma-diameter estimates:
2021 Oct. 30.83, 16.6, 1.3' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.9' tail in p.a. 105)

244P/Scotti
Total-magnitude and coma-diameter estimates:
2021 Nov. 08.01, 18.6, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

324P/La Sagra
Total-magnitude and coma-diameter estimates:
2021 Nov. 02.77, 21.0, -- (G. PappaLocation: Namibia (remote control); , 0.5-m Cassegrain reflector)

393P/Spacewatch-Hill
Total-magnitude and coma-diameter estimates:
2021 Nov. 02.07, 20.3, 0.2' (G. PappaLocation: Namibia (remote control); , 0.5-m Cassegrain reflector)

399P/PANSTARRS
Total-magnitude and coma-diameter estimates:
2021 Nov. 02.06, 21.0, 0.1' (G. PappaLocation: Namibia (remote control); , 0.5-m Cassegrain reflector)

402P/LINEAR
Total-magnitude and coma-diameter estimates:
2021 Oct. 31.94, 17.0, 0.1' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

C/2017 K2 (PANSTARRS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 21.73, 12.6, 2' (P. Dekelver, 0.3-m Newtonian reflector; 3.4' tail in p.a. 2)
2021 Nov. 17.75, 12.6, 2' (P. Dekelver, 0.3-m Newtonian reflector; 1.7' tail in p.a. 7)
2021 Nov. 11.75, 12.7, 2.6' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.04-deg tail in p.a. 360)
2021 Nov. 11.72, 12.1, 0.8' (W. Hasubick, 0.44-m Newtonian reflector)
2021 Nov. 10.72, 12.6, 2.8' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.06-deg tail in p.a. 4)
2021 Nov. 09.72, 12.6, 3' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.08-deg tail in p.a. 1)
2021 Nov. 08.71, 12.5, 2' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 06.74, 12.8, 2.2' (T. LehmannLocation: Weimar; , 0.279-m Newtonian reflector; 0.1-deg tail in p.a. 3)
2021 Nov. 05.75, 12.7, 2.4' (P. Dekelver, 0.3-m Newtonian reflector; 6.1' tail in p.a. 13)
2021 Nov. 01.79, 11.6, 1.3' (C. HarderLocation: Jeersdorf, f; , 0.531-m Newtonian reflector)
2021 Nov. 01.75, 12.2, 1.3' (M. Meyer, 0.254-m Newtonian reflector)

C/2019 F1 (ATLAS-Africano)
Total-magnitude and coma-diameter estimates:
2021 Oct. 31.76, 15.0, 0.4' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

C/2019 L3 (ATLAS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 21.79, 9.8, 5' (H. Kiiskinen, 0.4-m Ritchey-Chretien)
2021 Nov. 16.19, 10.1, 2.6' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 15.29, 9.9, 2' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 13.72, 10.2, 4' (C. Wyatt, 0.4-m Newtonian reflector; 5.8' tail in p.a. 290)
2021 Nov. 13.15, 9.9, 7.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 11.96, 9.6, 2.8' (A. KammererLocation: Teufelsmuehle (Black Forest), Germany; , 0.203-m Schmidt-Cassegrain)
2021 Nov. 11.45, 9.4, 8' (J. ChamboLocation: Mayhill, New Mexico; , 0.431-m Ritchey-Chretien; 13.0' tail in p.a. 304)
2021 Nov. 11.13, 9.6, 4' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 11.10, 10.2, 6' (P. Dekelver, 0.3-m Newtonian reflector; 10.9' tail in p.a. 304)
2021 Nov. 11.04, 9.8, 4' (P. Guzik, 25x100 binoculars)
2021 Nov. 10.98, 9.7, 15' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.28-deg tail in p.a. 302)
2021 Nov. 10.16, 11.0, 7.9' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 10.14, 9.7, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 10.14, 10.2, 4' (P. Dekelver, 0.3-m Newtonian reflector; 11.8' tail in p.a. 306)
2021 Nov. 10.09, 9.7, 3' (M. Meyer, 0.254-m Newtonian reflector)
2021 Nov. 10.06, 10.2, 4.51' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 09.93, 10.2, 2.4' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector; 4.5' tail in p.a. 305)
2021 Nov. 09.93, 10.5, 1.3' (M. Filipek, 0.25-m Newtonian reflector)
2021 Nov. 09.25, 10.3, 4.32' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 08.15, 9.6, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 08.03, 9.8, 2.8' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 07.08, 10.1, 4.5' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 4.5' tail in p.a. 305)
2021 Nov. 07.07, 10.4, 3' (M. ParadowskiLocation: Lublin; , 0.054-m refractor)
2021 Nov. 07.03, 10.5, 2' (V. DíazLocation: La Romana, Alicante, España; , 0.2-m Newtonian reflector)
2021 Nov. 06.99, 9.9, 4' (P. Guzik, 25x100 binoculars)
2021 Nov. 06.92, 10.2, 2.5' (M. KwintaLocation: Glanów; , 0.25-m Newtonian reflector)
2021 Nov. 06.92, 10.6, 1.2' (M. Filipek, 0.25-m Newtonian reflector)
2021 Nov. 06.31, 10.0, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 05.98, 9.9, 4' (P. GuzikLocation: Niżna Łąka, Poland; , 25x100 binoculars)
2021 Nov. 05.97, 10.0, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 05.94, 9.7, 3.5' (M. BielyLocation: Czech Republic, Brno; , 20x80 binoculars)
2021 Nov. 05.35, 9.7, 3' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 05.13, 9.5, 5' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain)
2021 Nov. 05.11, 10.0, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 05.08, 10.0, 8.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 04.96, 10.3, 2.3' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 04.32, 10.2, 3' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 04.07, 10.2, 2' (C. LabordenaLocation: Culla; , 0.2-m Schmidt-Cassegrain)
2021 Nov. 02.98, 10.0, 2.5' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 02.31, 10.4, 2' (J. de Souza Aguiar, 0.27-m Newtonian reflector)
2021 Nov. 02.29, 10.0, 2' (M. Goiato, 0.22-m Newtonian reflector)
2021 Nov. 02.12, 10.2, 1.8' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector; 6.0' tail in p.a. 275)
2021 Nov. 01.98, 10.0, 2.8' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 01.15, 10.3, 6' (P. Dekelver, 0.3-m Newtonian reflector; 11.8' tail in p.a. 306)
2021 Nov. 01.04, 10.1, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 01.01, 10.1, 3' (P. GuzikLocation: Lipowiec, Poland; , 25x100 binoculars)
2021 Oct. 31.99, 9.9, 2.9' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Oct. 31.93, 10.4, 2' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector)
2021 Oct. 31.91, 10.0, 1.5' (M. Filipek, 25x100 binoculars)
2021 Oct. 31.01, 10.5, 2.2' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Oct. 30.98, 10.0, 3' (P. Guzik, 25x100 binoculars)
2021 Oct. 30.91, 10.3, 2' (M. KwintaLocation: Glanów; , 0.33-m Newtonian reflector)
2021 Oct. 29.99, 10.0, 3.5' (W. Kutschera, 0.25-m Newtonian reflector; 0.67-deg tail)
2021 Oct. 29.99, 10.0, 12' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.14-deg tail in p.a. 306)

C/2019 O3
Total-magnitude and coma-diameter estimates:
2021 Nov. 09.90, 16.8, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

C/2019 T3 (ATLAS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 17.76, 17.5, 0.2' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 06.79, 16.6, 0.7' (T. LehmannLocation: Weimar; , 0.279-m Newtonian reflector; 0.5' tail in p.a. 46)
2021 Oct. 31.93, 17.4, 0.3' (P. Dekelver, 0.3-m Newtonian reflector; 0.4' tail in p.a. 114)
2021 Oct. 29.72, 16.9, 0.5' (S. FritscheLocation: Koeditz; , 0.1-m refractor)

C/2019 U5 (PANSTARRS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 06.73, 15.9, 0.6' (T. LehmannLocation: Weimar; , 0.279-m Newtonian reflector; 0.6' tail in p.a. 55)

C/2020 F5 (MASTER)
Total-magnitude and coma-diameter estimates:
2021 Nov. 26.88, 16.0, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 09.77, 15.3, 1.1' (S. FritscheLocation: Koeditz; , 0.1-m refractor)
2021 Nov. 06.85, 15.0, 1.5' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 0.13-deg tail in p.a. 189)

C/2020 F7 (Lemmon)
Total-magnitude and coma-diameter estimates:
2021 Oct. 31.97, 17.1, 0.2' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

C/2020 K1 (PANSTARRS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 06.76, 16.4, 0.7' (T. LehmannLocation: Weimar; , 0.279-m Newtonian reflector; 0.2' tail in p.a. 44)

C/2020 R7 (ATLAS)
Total-magnitude and coma-diameter estimates:
2021 Oct. 31.76, 16.2, 0.3' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)
2021 Oct. 31.06, 16.1, 0.9' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector; 1.1' tail in p.a. 58)

C/2020 T2 (Palomar)
Total-magnitude and coma-diameter estimates:
2021 Oct. 30.78, 12.2, 3.1' (T. LehmannLocation: Hakos; , 0.2-m Newtonian reflector)

C/2020 V2 (ZTF)
Total-magnitude and coma-diameter estimates:
2021 Nov. 22.23, 15.3, -- (G. van BuitenenLocation: Dordrecht, NL (G06); , 0.203-m Ritchey-Chretien)
2021 Nov. 11.19, 15.8, 0.8' (S. FritscheLocation: Koeditz; , 0.1-m refractor)
2021 Nov. 05.22, 15.8, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

C/2021 A1 (Leonard)
Total-magnitude and coma-diameter estimates:
2021 Nov. 26.49, < 8.2, 4' (D. ZubenelLocation: De Soto, Kansas, USA; , 0.152-m Newtonian reflector)
2021 Nov. 25.11, 7.8, 6' (P. Guzik, 10x50 binoculars)
2021 Nov. 25.10, 8.0, 5' (P. Guzik, 25x100 binoculars; 0.2-deg tail in p.a. 310)
2021 Nov. 23.23, 7.9, 4.5' (A. KammererLocation: Karlsruhe, Germany; , 0.125-m Schmidt-Cassegrain)
2021 Nov. 23.15, 8.4, 4' (U. Pilz, 0.32-m Newtonian reflector; 5.0-deg tail in p.a. 310)
2021 Nov. 23.12, 9.6, 6' (P. Dekelver, 0.3-m Newtonian reflector; 20.9' tail in p.a. 316)
2021 Nov. 22.17, 9.0, 7' (G. van BuitenenLocation: Dordrecht, NL (G06); , 0.203-m Ritchey-Chretien; 18.0' tail in p.a. 313)
2021 Nov. 22.16, 8.1, 6' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 22.15, 8.1, 5' (G. van BuitenenLocation: Dordrecht, NL (G06); , 0.13-m Newtonian reflector; 8.0' tail in p.a. 313)
2021 Nov. 18.24, 7.9, 8' (J. Gonzalez SuarezLocation: Sierra del Teleno, 1950 m, Leon, Spain; , 25x100 binoculars; 0.15-deg tail in p.a. 320)
2021 Nov. 17.51, 8.2, 7' (C. Hergenrother, 10x50 binoculars)
2021 Nov. 17.50, 8.5, 13.4' (C. HergenrotherLocation: remote iTelescopes T14; , 0.106-m refractor; 20.0' tail in p.a. 320)
2021 Nov. 17.47, 9.0, 8.2' (C. HergenrotherLocation: remote iTelescopes T14; , 0.106-m refractor; 26.0' tail in p.a. 325)
2021 Nov. 16.51, 8.9, 10.5' (J. ChamboLocation: Mayhill, New Mexico; , 0.106-m refractor; 20.0' tail in p.a. 318)
2021 Nov. 16.48, 8.5, 5.2' (D. ZubenelLocation: De Soto, Kansas, USA; , 0.152-m Newtonian reflector)
2021 Nov. 16.20, 8.4, 2.5' (M. DeconinckLocation: Aquarellia Observatory; , 0.25-m Cassegrain reflector; 5.0' tail in p.a. 280)
2021 Nov. 16.18, 9.6, 4' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 16.14, 8.7, 6' (P. Guzik, 25x100 binoculars; 0.3-deg tail in p.a. 320)
2021 Nov. 16.14, 8.4, 8' (P. Guzik, 10x50 binoculars)
2021 Nov. 15.52, 8.2, 5' (C. Hergenrother, 10x50 binoculars)
2021 Nov. 15.51, 8.4, 5' (C. Hergenrother, 30x125 binoculars; 6.0' tail in p.a. 310)
2021 Nov. 15.50, 9.3, 5.8' (C. HergenrotherLocation: remote iTelescopes T14; , 0.106-m refractor; 15.0' tail in p.a. 325)
2021 Nov. 15.49, 9.1, 11' (J. ChamboLocation: Mayhill, New Mexico; , 0.431-m Ritchey-Chretien; 34.0' tail in p.a. 309)
2021 Nov. 15.48, 9.0, 12.8' (C. HergenrotherLocation: remote iTelescopes T14; , 0.106-m refractor; 12.0' tail in p.a. 320)
2021 Nov. 15.24, 9.2, 8.1' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 15.21, 8.8, 3' (C. LabordenaLocation: Benlloch; , 11x80 binoculars)
2021 Nov. 14.25, > 8.5, -- (N. NovikovLocation: Russia, d. Enaberdino; , 0.15-m Newtonian reflector)
2021 Nov. 13.50, 8.5, 6' (C. Hergenrother, 10x50 binoculars)
2021 Nov. 13.50, 8.9, 5' (C. Hergenrother, 30x125 binoculars; 5.0' tail in p.a. 320)
2021 Nov. 13.23, 9.2, 10.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 11.51, 9.4, 5' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 11.45, 8.8, 11' (J. ChamboLocation: Mayhill, New Mexico; , 0.431-m Ritchey-Chretien; 19.0' tail in p.a. 322)
2021 Nov. 11.22, 8.7, 8' (J. Gonzalez Suarez, 25x100 binoculars; 0.4-deg tail in p.a. 320)
2021 Nov. 11.21, 9.2, 6' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain; 0.3-deg tail in p.a. 320)
2021 Nov. 11.16, 10.6, 4.8' (P. Dekelver, 0.3-m Newtonian reflector; 18.3' tail in p.a. 322)
2021 Nov. 11.15, 9.1, 18' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.38-deg tail in p.a. 322)
2021 Nov. 11.06, 9.2, 6' (P. Guzik, 10x50 binoculars)
2021 Nov. 10.23, 9.8, 10.16' (N. PaulLocation: Canaries MPC - G40; , 0.28-m Schmidt-Cassegrain; 16.0' tail in p.a. 320)
2021 Nov. 10.22, 9.5, 10.7' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 10.19, 10.2, 5.83' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 10.19, 10.7, 4.8' (P. Dekelver, 0.3-m Newtonian reflector; 16.4' tail in p.a. 319)
2021 Nov. 10.17, 9.4, 4' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector; 6.5' tail in p.a. 310)
2021 Nov. 10.15, 9.4, 4' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 10.11, 9.5, 4' (M. Meyer, 0.254-m Newtonian reflector; 0.1-deg tail in p.a. 310)
2021 Nov. 09.24, 10.2, 5.83' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 09.09, 11.0, 4' (P. Dekelver, 0.3-m Newtonian reflector; 8.3' tail in p.a. 322)
2021 Nov. 08.18, 10.3, 2.8' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 08.16, 9.6, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 07.49, 9.9, 3' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 07.15, 9.9, 6' (M. ParadowskiLocation: Lublin; , 0.054-m refractor)
2021 Nov. 07.14, 10.2, 3.2' (M. Kwinta, 0.19-m Newtonian reflector)
2021 Nov. 07.14, 9.8, 6' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 0.1-deg tail in p.a. 323)
2021 Nov. 07.14, 9.9, 5.2' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 0.1-deg tail in p.a. 323)
2021 Nov. 07.14, 10.0, 4.5' (M. ParadowskiLocation: Lublin; , 0.054-m refractor; 0.1-deg tail in p.a. 323)
2021 Nov. 07.13, 10.1, 4.5' (M. ParadowskiLocation: Lublin; , 0.054-m refractor)
2021 Nov. 07.08, 9.7, 6' (P. Guzik, 10x50 binoculars)
2021 Nov. 06.20, 11.1, 6' (P. Dekelver, 0.3-m Newtonian reflector; 10.6' tail in p.a. 325)
2021 Nov. 06.18, 9.5, 5' (T. KarhulaLocation: Virsbo, Sweden; , 18x50 binoculars)
2021 Nov. 06.02, 10.2, 4' (P. Guzik, 25x100 binoculars)
2021 Nov. 05.50, 10.4, 1' (K. WierzchosLocation: Oro Valley, AZ; , 0.317-m Newtonian reflector; 2.0-deg tail)
2021 Nov. 05.47, 11.0, 0.9' (D. ZubenelLocation: De Soto, Kansas, USA; , 0.318-m Newtonian reflector)
2021 Nov. 05.23, 9.7, 5' (J. Gonzalez Suarez, 0.203-m Schmidt-Cassegrain; 0.3-deg tail in p.a. 330)
2021 Nov. 05.20, 10.3, 7.5' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 05.18, 11.0, 4' (P. Dekelver, 0.3-m Newtonian reflector; 7.3' tail in p.a. 319)
2021 Nov. 05.17, 10.0, 2.6' (M. CollinsLocation: Everton; , 0.254-m Schmidt-Cassegrain)
2021 Nov. 05.12, 9.9, 3' (A. ScholtenLocation: Eerbeek; , 0.2-m Newtonian reflector)
2021 Nov. 04.49, 10.0, 4' (C. Hergenrother, 30x125 binoculars)
2021 Nov. 04.49, 9.9, 9' (J. ChamboLocation: Mayhill, New Mexico; , 0.431-m Ritchey-Chretien; 16.0' tail in p.a. 327)
2021 Nov. 04.20, 10.6, 3' (C. LabordenaLocation: Culla; , 0.2-m Schmidt-Cassegrain)
2021 Nov. 04.14, 11.1, 4.89' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 04.10, 10.7, 3' (D. BuczynskiLocation: Tarbatness MPC COde I81; , 0.35-m Schmidt-Cassegrain)
2021 Nov. 03.99, 10.0, 6' (A. Novichonok, 0.067-m refractor; 9.0' tail in p.a. 327)
2021 Nov. 03.20, 11.3, 3.38' (N. JamesLocation: 970; , 0.28-m Schmidt-Cassegrain)
2021 Nov. 02.15, 10.3, 3' (C. HarderLocation: Jeersdorf, h; , 0.298-m Newtonian reflector; 6.0' tail in p.a. 340)
2021 Nov. 01.19, 11.5, 4.8' (P. Dekelver, 0.3-m Newtonian reflector; 7.4' tail in p.a. 331)
2021 Nov. 01.08, 10.2, 5' (P. GuzikLocation: Niżna Łąka, Poland; , 25x100 binoculars)
2021 Oct. 31.15, 10.8, 6' (D. BuczynskiLocation: Tarbatness MPC COde I81; , 0.35-m Schmidt-Cassegrain)
2021 Oct. 30.18, 10.3, 7.3' (S. FritscheLocation: Koeditz; , 0.1-m refractor; 0.15-deg tail in p.a. 334)
2021 Oct. 30.10, 10.5, 3.5' (A. Novichonok, 0.067-m refractor; 4.0' tail in p.a. 325)
2021 Oct. 30.05, 11.3, 3.2' (D. BuczynskiLocation: Tarbatness MPC Code I81; , 0.35-m Schmidt-Cassegrain)
2021 Oct. 29.17, 11.5, 2.8' (G. van BuitenenLocation: Dordrecht, NL (G06); , 0.203-m Ritchey-Chretien; 3.5' tail in p.a. 325)
2021 Oct. 29.13, 11.5, 4' (P. Dekelver, 0.3-m Newtonian reflector; 6.1' tail in p.a. 324)
2021 Oct. 29.09, 11.0, 3' (P. Guzik, 0.326-m Newtonian reflector)

C/2021 O3 (PANSTARRS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 17.76, 18.0, 0.2' (P. Dekelver, 0.3-m Newtonian reflector)
2021 Nov. 06.82, 17.7, 0.5' (T. LehmannLocation: Weimar; , 0.279-m Newtonian reflector)
2021 Nov. 01.68, 17.6, -- (A. NovichonokLocation: ISON-Kitab observatory; , 0.36-m Ritchey-Chretien)

C/2021 P4 (ATLAS)
Total-magnitude and coma-diameter estimates:
2021 Nov. 26.91, 17.7, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

C/2021 U5 (Catalina)
Total-magnitude and coma-diameter estimates:
2021 Nov. 13.21, 18.9, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

P/2021 L2 (Leonard)
Total-magnitude and coma-diameter estimates:
2021 Nov. 01.91, 18.5, 0.1' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

P/2021 N2 (Fuls)
Total-magnitude and coma-diameter estimates:
2021 Nov. 08.03, 16.3, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)

P/2021 U1 (Wierzchos)
Total-magnitude and coma-diameter estimates:
2021 Nov. 05.03, 18.8, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)
2021 Nov. 01.88, 19.0, 0.1' (G. PappaLocation: Namibia (remote control); , 0.2-m Cassegrain reflector)

P/2021 V2 (Fuls)
Total-magnitude and coma-diameter estimates:
2021 Nov. 13.10, 19.3, 0.4' (P. CarsonLocation: Fegenal de la Sierra; , 0.315-m Cassegrain reflector)