Comet P/2019 Y2 (FULS) D. C. Fulsは、2019年12月21日UT、Mt Lemmon サーベイ (G96)によって彗星らしい天体 (PCCP C1N4PQ2)として通報した。15"の集光したコマとp.a.280°に35" の尾がある。 彗星機能の追加報告は次の通り： OC Date Reporter Coma Tail PA Exposures G40 Dec. 23 B. Ltkenhner 8" 20" 300 H06 Dec. 22 H. Sato 8"x12" 16x60s 595 Dec. 24 L. Bittesini 5" 15" 300 60x60s T12 Dec. 24 D. J. Tholen 6" 293 K88 Dec. 27 K. Sarneczky 10" 40" 280-300 9x120s Q11 Dec. 27 H. Sato 10" 12" 303 10x60s C10 Dec. 31 J.-F. Soulier 15" 28" 18 A71 Jan. 3 M. Jaeger 15" 40" 280-285 G40 Jan. 4 G. Gasparovic 5" 30" 300 25x50s I52 Jan. 4 D. C. Fuls 290 703 Jan. 4 T. A. Pruyne 13" 300 H06 Jan. 4 H. Sato 18" 50" 285 8x60s A71 Jan. 6 M. Jaeger 15" 45" 280 X02 Jan. 7 E. Bryssinck 15" 19" 286-306 12x120s 585 Jan. 7 A. Baransky 12" 1' 288 30x60s 発見位置は次のとおり、 2019 UT R.A. (2000) Decl. Mag. Observer Dec. 21.53226 12 26 24.26 + 2 41 27.9 18.8 Fuls 21.53653 12 26 24.67 + 2 41 25.7 18.8 " 21.54079 12 26 25.07 + 2 41 23.1 18.7 " 21.54506 12 26 25.45 + 2 41 21.9 18.7 " MPCの楕円軌道要素と位置推算表は次のとおり、 Orbital elements: P/2019 Y2 (Fuls) Epoch 2020 Feb. 1.0 TT = JDT 2458880.5 T 2020 Jan. 30.83335 TT Rudenko q 2.1300252 (2000.0) P Q n 0.14927596 Peri. 91.81945 -0.98866077 -0.12420352 a 3.5194607 Node 81.05241 +0.07935890 -0.90929532 e 0.3947865 Incl. 4.90131 +0.12748350 -0.39718446 P 6.60 From 155 observations 2019 Dec. 21-2020 Jan. 7, mean residual 0".7. P/2019 Y2 (Fuls) Epoch 2020 Mar. 12.0 TT = JDT 2458920.5 T 2020 Jan. 30.83842 TT 91.8 81.1 q 2.1300287 (2000.0) P Q n 0.14928147 Peri. 91.82155 -0.98866501 -0.12416981 a 3.5193743 Node 81.05227 +0.07932788 -0.90929794 e 0.3947706 Incl. 4.90131 +0.12746997 -0.39718901 P 6.60 From 155 observations 2019 Dec. 21-2020 Jan. 7, mean residual 0".7. P/2019 Y2 (Fuls) Epoch 2020 May 31.0 TT = JDT 2459000.5 T 2020 Jan. 30.85361 TT Rudenko q 2.1300703 (2000.0) P Q n 0.14929162 Peri. 91.82794 -0.98867901 -0.12405833 a 3.5192146 Node 81.05233 +0.07922538 -0.90930692 e 0.3947314 Incl. 4.90131 +0.12742512 -0.39720329 P 6.60 From 155 observations 2019 Dec. 21-2020 Jan. 7, mean residual 0".7. Ephemeris: Date TT R. A. (2000) Decl. Delta r Elong. Phase m1 2019 12 08 12 04 19.3 +04 34 53 2.1793 2.1668 76.2 26.2 18.2 ... 2019 12 23 12 28 41.7 +02 30 06 1.9988 2.1493 85.0 27.1 18.0 ... 2019 12 31 12 40 45.2 +01 31 38 1.9039 2.1422 90.0 27.3 17.9 ... 2020 01 06 12 49 15.9 +00 52 16 1.8339 2.1379 93.8 27.3 17.8 2020 01 07 12 50 38.1 +00 46 06 1.8223 2.1373 94.5 27.3 17.8 2020 01 08 12 51 59.4 +00 40 04 1.8108 2.1367 95.2 27.3 17.8 ... 2020 01 14 12 59 47.7 +00 06 25 1.7426 2.1337 99.2 27.1 17.7 ... 2020 01 22 13 09 13.9 -00 31 03 1.6542 2.1310 104.9 26.5 17.6 ... 2020 02 06 13 23 17.7 -01 16 07 1.5000 2.1305 116.4 24.5 17.4 (MPEC 2020-A91、CBET 4709)