* * * * * C/2018 Y1 (Iwamoto) * * * * *

Year Mn Day MM Mag Ref Scope Pwr coma DC tail p.a. Obs Site 2019 4 2.87 S 9.8 TK 20.3T 77 6 2/ GON Alto del Celleron - Benllera, León 2019 4 1.840 S 10.8 AQ 30.5T 54 1.4 0/ DIJ Burlage 2019 4 1.835 S 11.0 AQ 30.5T 54 2.8 1 BOU Burlage, Germany (Star of magnitude 12.4 at edge of coma.) 2019 3 31.838 S 10.8 AQ 25.4J 47 3 2 BOU Sint Annen (Some interference from star of magn. 12.3 in coma.) 2019 3 29.896 S 10.4 TK 15.5L 42 2.3 1/ DIJ Burlage 2019 3 25.867 S 10.3 TK 15.5L 42 1.4 2 DIJ Burlage 2019 3 24.83 S 10.5:TK 20.0L 80 & 2 2 SCH Eerbeek (Difficult. Only seen with averted vision.) 2019 3 24.826 S 10.2 AQ 15.6L 36 4 2/ BOU Sint Annen 2019 3 23.86 S 9.3 TK 20.3T 77 5 3 GON Alto del Castro, León 2019 3 22.818 S 10.3 TK 15.5L 42 2.2 3 DIJ Burlage 2019 3 11.96 S 8.7 TK 10.0B 20 8 2/ GOI Araçatuba 2019 3 11.830 S 8.9 TK 8.0B 15 7.5 2/ DIJ Burlage (Moonlight.) 2019 3 9.87 S 8.2 TK 10.0B 25 10 3/ GON Alto del Trichero, León 2019 3 9.86 S 8.5 TK 20.3T 77 8 3/ GON Alto del Trichero, León 2019 3 9.837 S 8.9 TK 8.0B 15 6 2/ BOU Sint Annen 2019 3 9.785 S 9.1 TK 8.0B 15 6 3 DIJ Burlage 2019 3 8.938 S 9.0 TK 8.0B 15 6 3/ DIJ Burlage 2019 3 7.819 S 9.0 TK 8.0B 15 6 2/ DIJ Burlage 2019 3 5.806 S 8.6 TK 8.0B 15 6.6 3 DIJ Burlage 2019 3 5.804 S 8.6 TK 8.0B 15 8 3/ BOU Sint Annen 2019 3 4.866 S 8.5 TA 8.0B 15 8.5 2/ BOU Sint Annen 2019 3 4.820 S 8.8 TK 8.0B 15 7.7 1/ DIJ Burlage 2019 3 4.42 M 9.3 TK 25.0L 39 10.5 4 WYA Walcha, NSW (Low altitude 19.0°. Coma enhances well in Swan Band filter while central condensation appears to dim in Swan Band.) 2019 3 3.41 S 8.6 TK 7.0B 11 9.5 3 WYA Walcha, NSW (Difficult. Diffuse outer coma, slight brightening to centre.) 2019 3 2.91 S 7.5 TK 4.5R 12 13 3/ GON Collado del Fresno - Aramo, Asturias 2019 3 2.90 S 7.8 TK 10.0B 25 10 3/ GON Collado del Fresno - Aramo, Asturias 2019 2 27.92 S 8.0 TK 8.0B 15 &12 2 SCH Eerbeek (Comet in field with several weak stars.) 2019 2 27.906 S 8.3 TK 8.0B 15 10 3 DIJ Burlage 2019 2 27.901 S 8.1 TK 8.0B 15 9 3 BOU Burlage, Germany 2019 2 27.010 S 7.8 TK 5.0B 10 10 2 DIJ Burlage 2019 2 26.91 S 8.3 TK 8.0B 15 &12 3 SCH Eerbeek 2019 2 26.885 S 8.0 TK 8.0B 15 9 3 BOU Sint Annen 2019 2 25.874 S 7.7 HI 5.0B 10 10 3 BOU Sint Annen 2019 2 25.87 S 8.2 TK 8.0B 15 &13 2 SCH Eerbeek (A lot of weak stars near comet.) 2019 2 25.825 S 8.8 AC 32.0L 57 4 2 LOO Genk 2019 2 25.797 S 7.7 TK 5.0B 10 11 2/ DIJ Burlage 2019 2 25.00 S 6.8 TK 4.5R 12 15 3/ GON Puerto de Aralla, León 2019 2 24.935 S 7.7 HI 8.0B 15 10 3/ BOU Sint Annen 2019 2 24.92 S 8.0 TK 8.0B 15 13 3 SCH Eerbeek 2019 2 24.44 S 7.7 AA 5.0B 10 8 SEA Cowra, NSW (Enhanced through Swan Band filter.) 2019 2 23.94 S 8.0 TK 8.0B 15 &11 2 SCH Eerbeek 2019 2 23.881 S 7.8 TK 5.0B 10 9.5 2 DIJ Burlage 2019 2 23.869 S 7.7 HI 8.0B 15 10 3 BOU Sint Annen 2019 2 23.51 S 8.3 TJ 40.0L 36 11 4 YOS Mt. Hanadate, Ibaraki 2019 2 23.51 S 7.7 TJ 7.0R 10 15 3/ YOS Mt. Hanadate, Ibaraki (Bright and well visible.) 2019 2 22.43 S 7.2:AA 5.0B 10 SEA Cowra, NSW (Enhanced through Swan Band filter. Close to bright star making estimate very approximate.) 2019 2 15.180 S 6.7 HI 5.0B 10 16 3/ BOU Burlage, Germany 2019 2 15.173 S 6.8 TK 5.0B 10 12 5 DIJ Burlage 2019 2 15.16 S 6.9 TK 5.6B 8 &13 5 SCH Eerbeek 2019 2 15.114 S 7.3 TK 5.0B 7 7 4 LOO Genk (Moonlight.) 2019 2 13.15 S 5.7 TK 4.5R 12 22 4/ GON Puerto de Aralla, León 2019 2 13.14 S 5.5 TK 0.0E 1 30 5 GON Puerto de Aralla, León 2019 2 12.03 S 5.5 TK 0.0E 1 30 5 GON Collada de la Cobertoria, Asturias 2019 2 12.02 S 5.6 TK 4.5R 12 25 4 GON Collada de la Cobertoria, Asturias 2019 2 11.982 S 6.6 TK 5.0B 10 18 5 DIJ Burlage 2019 2 11.917 S 6.9 HI 5.0B 7 10 4 LOO Genk (Moonlight.) 2019 2 11.64 M 6.6 YG 5.0B 7 30 4 WYA Walcha, NSW (Coma large and diffuse, transparent outer coma, opaque inner coma, moderately condensed centre.) 2019 2 11.09 S 6.6 TK 5.6B 8 &20 6 SCH Eerbeek 2019 2 11.084 S 7.7 HI 10.0B 14 9 4 LOO Genk 2019 2 10.29 S 6.2 TK 5.0B 7 30 4 GOI Araçatuba 2019 2 9.69 M 7.0 TK 5.0B 7 17.4 5/ WYA Walcha, NSW (Close to bright stars. Sometimes appears to have a faint stellar pseudo nucleus.) 2019 2 9.50 B 7.3 AA 10.0B 25 16 4 SEA Cowra, NSW (Moderately enhanced using Swan Band filter.) 2019 2 9.25 S 6.3 TK 5.0B 7 30 4/ GOI Araçatuba 2019 2 8.17 S 6.5 TK 5.0B 7 25 4/ GOI Araçatuba 2019 2 7.963 S 7.1 TK 5.0B 10 19 5 DIJ Burlage 2019 2 7.12 S 6.7 TK 5.0B 7 20 4 GOI Araçatuba (In 20x100B, tail 20' in p.a. 295 degrees.) 2019 2 6.04 S 5.9 TK 4.5R 12 30 3 1.3 300 GON Collada de la Cobertoria, Asturias 2019 2 4.68 M 7.2 TK 5.0B 7 25 4 WYA Walcha, NSW (Coma diffuse, opaque moderately condensed centre.) 2019 2 4.027 S 7.2 TK 5.0B 10 12 3 DIJ Burlage 2019 2 4.003 S 7.1 HI 5.0B 10 17 1/ BOU Burlage, Germany 2019 2 3.69 M 7.2 TK 5.0B 7 21 4 WYA Walcha, NSW (Diffuse, transparent outer coma, opaque inner coma. Moderately condensed. Enhances well in Swan band filter.) 2019 2 3.10 S 6.1 TK 4.5R 12 35 2/ 3.5 300 GON Matadeon de los Oteros, León (Very wide and diffuse outer coma.) 2019 1 21.25 S 9.3 TK 22.0L 60 6 4 GOI Araçatuba (Total lunar eclipse.) 2019 1 21.219 S 9.2 TK 15.5L 24 6 2/ BOU Burlage, Germany (Altitude 16.4°. Observed during total lunar eclipse.) 2019 1 21.217 S 9.6 TK 15.5L 24 5 2 DIJ Burlage 2019 1 21.22 S 7.3 TK 5.0B 10 15 3 GON Matadeon de los Oteros, León 2019 1 21.21 S 7.5 TK 10.0B 25 15 3 GON Matadeon de los Oteros, León 2019 1 21.19 S 8.1 TK 20.3T 77 12 3/ 0.3 290 GON Matadeon de los Oteros, León (Observed during total moon eclipse. From dark rural skies the comet shows a faint tail and wide coma. Altitude 25°.) 2019 1 14.68 M 10.0 TK 25.0L 39 6.4 4 WYA Walcha, NSW (Enhances well in Swan Band filter. Coma slightly elongated to the NE approximately. Opaque centre, fading to edges.) 2019 1 14.26 S 8.2 TK 10.0B 25 10 2 GON Alto del Castro - Aralla, León (From dark mountain skies the comet shows a wide and diffuse outer coma. Altitude 25°.) 2019 1 14.25 S 8.7 TK 20.3T 77 8 3 GON Alto del Castro - Aralla, León 2019 1 12.62 S 9.7 TK 25.0L 39 5 3 WYA Walcha, NSW (Enhances in Swan Band filter. Opaque centre, pale aqua-blue in colour. Faint outer coma. Low altitude 16.8°.) 2019 1 7.67 M 10.2 TK 25.0L 39 4.5 3/ WYA Walcha, NSW (Enhances in Swan Band filter. Moderately condensed.) 2019 1 7.26 S 8.9 TK 20.3T 77 8 2/ GON Alto del Castro - Aralla, León (Altitude 22°.) 2019 1 6.83 S 11.6 TJ 40.0L 75 2.4 1 YOS Mt. Hanadate, Ibaraki (I could see Iwamoto's comet for the first time, since I missed his past two comets C/2013 E2 and C/2018 V1. Diffuse, very weakly condensed.) 2019 1 2.25 S 9.2 TK 20.3T 77 5 2/ GON Alto del Castro - Aralla, León (Altitude 19°.) 2018 12 30.69 S 11.3 AQ 25.0L 83 1.4 2/ WYA Walcha, NSW (Moonlight. Coma diffuse, slight brightening to centre. Enhances in Swan band filter. Visible at 39x but just above background sky threshold under moonlit conditions, difficult to obtain measurement at that scale. Elongation from the Moon is approximately 21 degrees.) 2018 12 30.29 S 10.9:TK 22.0L 160 1.5 4 GOI Araçatuba (Moonlight.)