* * * * * 78P/Gehrels 2 * * * * *

Year Mn Day MM Mag Ref Scope Pwr coma DC tail p.a. Obs Site 2019 12 28.71 S 15.3 AQ 40.0L 261 0.3 3 WYA Walcha, NSW (Coma small and diffuse, difficult.) 2019 1 6.81 S 11.7 AQ 20.3T 133 3 3 GON Alto del Castro - Aralla, León 2018 11 30.38 S[13.8 AU 40.0L 257 !0.8 YOS Kita-karuizawa, Gunma 2018 11 1.53 M 13.5 AQ 40.6L 165 1.0 3/ CAM Katherine, NT 2018 10 29.50 M 13.5 AQ 40.6L 165 0.8 3 CAM Katherine, NT 2018 10 11.59 M 13.5 AQ 40.6L 165 1.0 3/ CAM Katherine, NT 2018 10 9.53 M 13.5 AQ 40.6L 165 1.0 4 CAM Katherine, NT 2018 10 7.56 M 13.5 AQ 40.6L 165 1.0 3 CAM Katherine, NT 2018 10 7.44 S 14.1 AU 40.0L 257 0.6 2 YOS Kita-karuizawa, Gunma (Unexpectedly diffuse.) 2018 10 6.55 M 13.5 AQ 40.6L 165 1.0 3 CAM Katherine, NT 2018 10 4.58 M 13.7 AQ 40.6L 165 0.8 3/ CAM Katherine, NT 2018 10 3.56 M 13.8 AQ 40.6L 165 0.6 3 CAM Katherine, NT 2018 9 17.66 S[13.8 AU 40.0L 257 !0.6 YOS Kita-karuizawa, Gunma
2012 4 8.85 S 10.8 TK 20.3T 100 2.5 3 GON Pandorado, León (End of astronomical twilight.) 2012 3 11.84 S 10.5 TK 20.3T 77 3 3 GON Alto del Castro - Aralla, León 2012 2 20.83 S 10.5 TK 20.3T 77 5 3 GON Collada de la Cobertoria, Asturias 2012 2 19.86 S 12.2 HS 20.3T 67 1.5 3 BIV 2012 2 18.86 S 12.2 TK 20.3T 67 1.5 3 BIV 2012 2 17.85 S 11.9 TK 20.3T 67 2.0 2 BIV 2012 2 15.86 S 12.2 HS 20.3T 67 1.0 5 BIV 2012 2 10.68 V 11.5 UD 6.7R 4.0 NOV Nizhniy Arkhyz (remotely) 2012 1 24.73 V 11.3 UD 6.7R 3.8 NOV Nizhniy Arkhyz (remotely) 2012 1 21.75 V 11.6 UD 7.2R 3.2 NOV Nizhniy Arkhyz (remotely) 2012 1 20.68 V 11.3 UD 7.2R 4.1 NOV Nizhniy Arkhyz (remotely) 2012 1 1.97 S 10.8 AU 22.0L 160 1.5 2/ GOI Araçatuba (Moonlight.) 2011 12 22.80 S 10.5 TK 20.3T 77 5 3/ GON Collada del Fresno - Sierra del Aramo, Asturias 2011 12 14.44 S 11.7 GA 25.4L 71 3 SEA Cowra, NSW 2011 11 28.00 S 10.6 AU 22.0L 120 3 3 GOI Araçatuba 2011 11 27.821 S 12.2 TA 30.5T 73 2 2/ DIJ Burlage 2011 11 27.815 S 11.8 TA 30.5T 73 2.5 2/ BOU Burlage, Germany 2011 11 26.76 S 9.8 TK 10.0B 25 6 3 GON Alto del Castro - Aralla, León 2011 11 24.41 S 10.9 TJ 40.0L 144 2.0 6 YOS Kita-karuizawa, Gunma (Strongly condensed and easy to see. I also observed it on Nov. 25. But I cannot determine the magnitude because I failed to select proper comparison stars.) 2011 11 23.96 S 10.8 AU 22.0L 160 3 4 GOI Araçatuba 2011 11 18.48 S 11.4 GA 10.0B 25 3 SEA Cowra, NSW 2011 11 17.82 S 9.8 TK 20.3T 77 5 3 GON Angliru - Sierra del Aramo, Asturias 2011 11 15.47 S 11.6 GA 25.4L 71 3 4 SEA Cowra, NSW (Comet faintly visible in 25x100 binocular telescope.) 2011 11 1.10 S 10.6 TK 22.0L 160 3 4 GOI Araçatuba 2011 10 29.97 S 10.3 TK 20.3T 77 6 3/ GON Alto del Castro - Aralla, León 2011 10 27.12 S 10.8 AU 22.0L 160 3 4 GOI Araçatuba 2011 10 23.830 S 11.7 TA 30.5T 95 1.7 3/ BOU Burlage, Germany 2011 10 23.828 S 11.9 TA 30.5T 95 2 4 DIJ Burlage 2011 10 21.89 S 11.4 TK 20.3T 67 2.0 6 BIV Pico-Veleta, Spain 2011 10 20.96 S 10.5 TK 20.3T 77 5 4 GON Alto del Castro - Aralla, León 2011 10 19.89 S 11.6 TK 20.3T 67 2.0 6 BIV Pico-Veleta, Spain 2011 10 19.48 S 12.0 GA 10.0B 25 SEA Cowra, NSW 2011 10 18.91 S 11.3 TK 20.3T 67 2.2 5 BIV Pico-Veleta, Spain 2011 10 16.43 S 12.1 GA 25.4L 71 2 SEA Cowra, NSW (Comet glimpsed in 25x100 binocular telescope.) 2011 10 15.81 S 10.3 TK 20.3T 77 5 3/ GON Aralla, León 2011 10 7.72 S 11.5 TA 40.0L 75 1.8 5 YOS Kita-karuizawa, Gunma (Bright and easy to see after the moonset. Moderately condensed.) 2011 10 1.833 S 12.3 TA 30.5T 117 1.5 4/ DIJ Burlage 2011 10 1.830 S 12.0 TA 30.5T 117 1.6 4/ BOU Burlage, Germany 2011 10 1.08 S 11.0 TK 20.3T 77 3.5 3/ GON Alto del Castro - Aralla, León (Star of mag. 12.9 [GSC] inside the coma.) 2011 9 29.882 S 11.9 TA 30.5T 117 1.5 4/ DIJ Burlage 2011 9 29.878 M 12.1 TA 30.5T 117 1.5 5 BOU Burlage, Germany 2011 9 28.12 S 11.0 AU 22.0L 160 2.5 3 GOI Araçatuba 2011 9 24.88 S 12.1 HS 40.7L 71 1.3 7 BIV Ambeyrac 2011 9 24.87 S 10.8 TK 20.3T 77 4 3/ GON Alto del Castro - Aralla, León 2011 9 23.86 S 12.2 HS 40.7L 71 1.0 6 BIV Ambeyrac 2011 9 22.97 S 11.9 HS 40.7L 71 1.2 7 BIV Ambeyrac 2011 9 19.90 S 10.8 TK 20.3T 77 4 4 GON Alto del Castro - Aralla, León (Comet significantly brighter than two weeks ago, showing a larger coma.) 2011 9 19.12 S 11.5 AU 22.0L 160 2 4 GOI Araçatuba 2011 9 7.06 S 12.5 TA 20.3T 133 1.2 5 GON Alto del Castro - Aralla, León 2011 9 3.04 S 12.8 TA 20.3T 100 1.0 6 GON Pandorado, León 2011 9 1.17 S 12.6 AU 22.0L 160 1 4 GOI Araçatuba 2011 8 29.91 S 13.5 UD 20.3L 133 0.5 5 IVA Saratov 2011 8 26.94 S 13.2 TA 20.3T 133 1.0 6 GON Alto del Castro - Aralla, León 2011 8 25.88 S 13.5 UD 25.4L 171 0.7 6 IVA Saratov
2005 5 3.46 S[12.7 AU 40.0L 144 !1.0 YOS Gunma, Japan (Finally, it became invisible. But the limiting magnitude is not so faint due to the low altitude. Therefore it is uncertain whether the comet became much fainter or not.) 2005 4 5.45 S 12.9 AU 40.0L 144 1.6 0/ YOS Ibaraki, Japan (Very faint, widely diffused. Hard to see it.) 2005 4 1.90 S 12.6:HS 40.7L 116 1.4 2 BIV Poigny-la-Forêt 2005 3 11.88 S 12.8 TK 20.3T 100 0.8 2 GON Camposagrado, León 2005 3 9.817 S 12.7 AU 31.0J 143 1.2 2 BOU Sint Annen 2005 3 8.48 S 12.6 AU 40.0L 144 1.3 2/ YOS Ibaraki, Japan (Still visible. Similar to the look in February, very diffuse. It was in the Hyades, and many bright stars were in the field of view.) 2005 2 10.792 S 12.3 AU 31.0J 89 1.7 2 BOU Sint Annen 2005 2 7.832 S 12.5 AU 31.0J 89 1.3 2/ DIJ Sint Annen 2005 2 7.828 S 12.1 AU 31.0J 89 2.0 2 BOU Sint Annen 2005 2 6.801 S 12.2 AU 31.0J 89 1.8 3/ DIJ Lauwersoog 2005 2 6.799 S 12.2 AU 31.0J 89 2.0 2/ BOU Lauwersoog 2005 2 5.46 S 12.2 HS 40.0L 144 1.4 3 YOS Ibaraki, Japan (Surprising transfiguration. Although it had been strongly condensed until January, now it is very diffuse.) 2005 2 4.88 S 12.1 TK 25.6L 84 1.3 5 BIV Poigny-la-Forêt 2005 1 31.91 S 11.9 TK 20.3T 77 1.5 3 GON Soto y Amío, León 2005 1 14.914 M 11.5 AU 31.0J 89 2.5 2/ DIJ Sint Annen 2005 1 14.908 S 11.5 AU 31.0J 89 2.2 3 BOU Sint Annen 2005 1 12.91 S 11.5 TK 25.6L 42 1.5 5 BIV Poigny-la-Forêt 2005 1 12.783 S 11.5 AU 31.0J 72 2.0 3/ BOU Sint Annen 2005 1 8.43 S 11.2 TJ 40.0L 144 2.0 6/ YOS Ibaraki, Japan (Still strongly condensed.) 2005 1 7.90 S 10.9 TK 20.3T 77 2.5 4 GON Aralla, León 2005 1 3.85 S 10.9 TK 20.3T 77 2.5 4 GON Aralla, León 2005 1 2.809 S 11.0 AU 31.0J 72 2.5 3/ DIJ Langelo 2005 1 2.807 S 11.3 AU 31.0J 72 2.3 3/ BOU Langelo 2005 1 2.80 S 11.2 TK 25.6L 42 1.8 6 BIV Poigny-la-Forêt 2004 12 20.09 S 11.2 TK 25.6L 42 2.0 5 BIV Poigny-la-Forêt 2004 12 19.883 S 11.0 AU 25.4J 72 2.2 3/ BOU Sint Annen (Comet well visible, despite moonlight.) 2004 12 18.02 S 11.0 TK 25.6L 42 2.0 5 BIV Poigny-la-Forêt 2004 12 16.98 S 10.7 TK 25.6L 42 2.5 5 BIV Poigny-la-Forêt 2004 12 16.953 S 11.0 AU 31.0J 72 2.0 3/ DIJ Sint Annen 2004 12 16.951 M 11.0 AU 31.0J 72 2.4 4 BOU Sint Annen 2004 12 14.95 S 10.4 TK 10.0B 25 3 5 GON Sierra del Aramo, Asturias 2004 12 12.92 S 10.8 TK 20.3T 77 3 5 GON Sierra del Aramo, Asturias 2004 12 12.92 S 10.4 TK 20.3L 40 2.0 6 BIV Haute Provence Obs. 2004 12 11.93 S 10.4 TK 20.3L 40 3.0 5 BIV Haute Provence Obs. 2004 12 11.41 S 11.2 TJ 40.0L 75 1.9 7 YOS Gunma, Japan (Getting a bit fainter, but still strongly condensed.) 2004 12 8.91 S 10.7 TK 25.6L 42 2.0 5 BIV Poigny-la-Forêt 2004 12 8.774 S 10.9 AU 31.0J 72 1.4 5 DIJ Sint Annen 2004 12 8.770 M 10.7 AU 31.0J 72 2.5 4/ BOU Sint Annen 2004 12 6.00 M 10.4 TK 20.3T 77 2.0 4 GRA Fjellhamar (Surface brightness similar to NGC 205. Difficult to see due to a quite bright sky background. NEL = 5.0 [approx.].) 2004 12 5.94 S 10.3 TK 20.3T 77 3 5 GON Camposagrado, León 2004 11 30.49 S 10: AA 10.0B 25 SEA Cowra, NSW (Comet close to star.) 2004 11 21.92 B 9.7 TK 13.0L 45 1.5 3/ RES Poznan 2004 11 21.15 M 10.2 TK 25.4L 59 2.5 5/ GRA Hågår Observatory, Eina (This comet showed a rather bright and well condensed coma.) 2004 11 21.024 S 10.2 AU 31.0J 58 3.4 4/ DIJ Sint Annen 2004 11 21.022 M 10.3 AU 31.0J 58 2.5 5 BOU Sint Annen 2004 11 17.990 S 9.6 TK 12.0B 20 3 7 LOO Le Castellard, France (Short tail of 6’.) 2004 11 16.917 S 9.3 TK 12.0B 20 2.5 6 LOO Le Castellard, France (Sharp false nucleus and short tail of 8’.) 2004 11 16.85 B 9.9 TK 13.0L 45 1.5 2/ RES Poznan 2004 11 16.53 S 10.1 TK 10.0B 25 2 6 MAT Stockport Observatory, SA (Surprisingly bright. In 38.0-cm reflector, a bright stellar nucleus is visible with a short tail in p.a. 280 deg.) 2004 11 16.07 S 9.8 TK 10.0B 25 3 5 GON Camposagrado, León 2004 11 16.06 S 10.2 TK 20.3T 77 2.5 6 GON Camposagrado, León 2004 11 15.813 S 9.1 TK 12.0B 20 3 6 LOO Le Castellard, France 2004 11 15.46 S 9.9 AA 10.0B 25 SEA The Entrance, NSW 2004 11 14.95 S 10.8 HS 25.6L 42 1.5 6 0.06 270 BIV Poigny-la-Forêt 2004 11 14.931 S 9.0 TK 12.0B 20 3 6 LOO Le Castellard, France 2004 11 14.808 M 10.6 AU 31.0J 58 2.6 5 BOU Sint Annen 2004 11 14.44 S 9.9 AA 10.0B 25 4.0 SEA Cowra, NSW 2004 11 14.06 B 10.0 TK 13.0L 45 1.4 2/ RES Poznan 2004 11 13.95 M 10.5 TK 25.4L 76 3 5 GRA Hågår Observatory, Eina 2004 11 13.795 S 8.8 TK 12.0B 20 3 6 LOO Le Castellard, France (Slightly elongated coma.) 2004 11 13.48 S 10.0 AA 10.0B 25 SEA Cowra, NSW 2004 11 13.06 S 10.4 TK 20.3T 77 2.5 6 GON Camposagrado, León 2004 11 12.44 S 10.0 AA 10.0B 25 SEA Cowra, NSW 2004 11 9.52 S 10.3 TJ 40.0L 36 2.1 6 4.2m 255 YOS Gunma, Japan 2004 11 9.50 S 10.1 AA 10.0B 25 SEA Cowra, NSW 2004 11 8.974 M 10.7 AU 25.4J 58 2.3 5 BOU Sint Annen 2004 11 4.847 M 10.9 AU 25.4J 72 1.7 5/ BOU Sint Annen 2004 10 21.934 M 11.3 AU 31.0J 72 2.0 5 BOU Sint Annen 2004 10 21.19 S 11.2 TK 25.6L 42 1.6 6 0.05 270 BIV Poigny-la-Forêt 2004 10 18.926 S 11.2 AU 31.0J 72 1.9 3/ DIJ Sint Annen 2004 10 18.924 M 11.3 AU 31.0J 72 1.9 4/ BOU Sint Annen 2004 10 18.92 S 11.5 HS 40.7L 116 1.5 6 BIV Poigny-la-Forêt 2004 10 16.02 S 11.5 TK 25.6L 42 1.5 6 0.07 260 BIV Poigny-la-Forêt 2004 10 15.56 M 11.0 TJ 40.0L 75 1.1 7 1.7m 260 YOS Gunma, Japan 2004 10 15.54 S 11.4 GA 25.4L 71 SEA Cowra, NSW 2004 10 12.99 S 11.5 TK 25.6L 42 1.4 5 0.06 270 BIV Poigny-la-Forêt 2004 10 12.117 M 11.6 AU 31.0J 72 1.6 4/ BOU Garmerwolde 2004 10 10.944 S 11.4 AU 31.0J 72 1.8 4 DIJ Sint Annen 2004 10 10.942 M 11.6 AU 31.0J 72 1.7 5 BOU Sint Annen 2004 10 9.61 S 12.0 TK 38.0L 150 2 3 MAT Stockport Observatory, SA 2004 10 8.973 S 11.4 AU 31.0J 72 1.4 4 DIJ Sint Annen 2004 10 8.972 M 11.7 AU 31.0J 72 1.5 4/ BOU Sint Annen 2004 10 7.926 S 11.5 AU 31.0J 109 1.5 4/ DIJ Sint Annen 2004 10 7.925 M 11.8 AU 31.0J 109 1.5 5 BOU Sint Annen (Some interference from nearby star of magn. 8.8 [TK].) 2004 10 6.92 S 11.6 HS 25.6L 84 1.3 6 0.04 260 BIV Poigny-la-Forêt 2004 9 24.13 S 12.0 TK 25.6L 42 1.2 6 0.06 270 BIV Poigny-la-Forêt 2004 9 21.97 M 11.9 SK 20.3L 63 2 5 GUZ Krosno 2004 9 19.04 M 11.9 SK 20.3L 63 2 5 GUZ Krosno 2004 9 18.96 S 12.0 TK 13.0L 45 0.5 4 RES Ostrorog 2004 9 17.98 M 11.9 SK 20.3L 63 2 5 GUZ Krosno 2004 9 17.93 S 12.1 TK 13.0L 45 0.5 4 RES Ostrorog 2004 9 17.70 S 11.7 AU 40.0L 144 1.1 7 1.7m 240 YOS Gunma, Japan 2004 9 17.10 S 12.2 HS 40.7L 58 1.3 7 0.06 270 BIV Ablis 2004 9 17.03 M 11.8 SK 20.3L 63 2 5 GUZ Krosno (Comet seems to be a bit brighter than a few days ago. Bigger and brighter than C/2004 Q1.) 2004 9 17.02 S 12.1 TK 20.3T 77 1.8 3 GON Alto del Castro, León 2004 9 16.124 S 12.2 AU 25.4J 88 1.2 4 BOU Garmerwolde 2004 9 15.14 S 12.3 HS 25.6L 42 1.3 7 0.05 270 BIV Poigny-la-Forêt 2004 9 14.948 S 12.2 AU 25.4J 88 1.2 4 BOU Sint Annen 2004 9 14.92 M 12.2 SK 20.3L 63 1.5 5 GUZ Krosno 2004 9 10.98 M 12.1 TK 20.3L 63 1.2 6 GUZ Krosno 2004 9 8.96 S 12.8 HS 40.7L 116 1.0 6 0.03 260 BIV Ablis 2004 9 8.93 M 12.3 TK 20.3L 63 1.2 5 GUZ Krosno (Easily visible, small, well condensed object.) 2004 8 22.035 S 12.7 AU 31.0J 109 1 3 DIJ Sint Annen 2004 8 22.033 S 12.7 AU 31.0J 109 1.0 4/ BOU Sint Annen 2004 8 21.76 S 12.4 AU 40.0L 144 1.1 5/ YOS Gunma, Japan 2004 8 21.14 S 12.5 TK 20.3T 100 1.0 3 GON Alto del Castro - Aralla, León 2004 8 20.015 S 13.2 AU 31.0J 109 0.7 3/ DIJ Sint Annen 2004 8 20.010 S 12.8 AU 31.0J 109 0.9 4/ BOU Sint Annen 2004 8 15.96 S 12.6 SK 20.3L 63 0.8 4 GUZ Krosno 2004 8 13.14 S 12.8 TK 20.3T 100 0.8 4 GON Alto del Castro - Aralla, León 2004 7 28.041 S 13.3 AC 31.0J 143 0.7 4 DIJ Sint Annen 2004 7 28.038 S 13.4 AC 31.0J 143 0.6 5 BOU Sint Annen (Small, well condensed object. Comparison stars with good V-magnitudes used from nearby AAVSO-sequence of TT Ari.)