Comet P/2004 R1 = 2015 HC10 (McNaught) G. V. Williams, F. Mancaと P. Sicoliは、それぞれ L. Allen と D. JamesがCerro Tololo-DECam. の4-m反射望遠鏡で発見し、小惑星センターのNEOCP webpageに公表後、2015 HC10と仮符号がつけられた 小惑星状天体をP/2004 R1とリンクした。 追加観測が、T. H. Bressiによって、Spacewatch 1.8-m f/2.7反射望遠鏡で得られた。 MPC 793500の中野主一氏の予報に対し、Delta(T)は、+5.0 daysであった。 検出位置は次のとおり、 2015 UT R.A. (2000) Decl. Mag. Observer Apr. 18.98923 12 34 10.77 -16 02 41.1 22.4 Allen 18.99246 12 34 10.44 -16 02 39.7 " 18.99562 12 34 10.13 -16 02 38.5 " 18.99877 12 34 09.80 -16 02 37.1 " 19.99406 12 32 31.12 -15 55 24.7 22.2 " 19.99742 12 32 30.79 -15 55 23.2 " 20.00091 12 32 30.42 -15 55 21.8 " 20.00435 12 32 30.08 -15 55 20.3 " 20.22641 12 32 07.59 -15 53 54.1 21.8 Bressi 20.23352 12 32 06.87 -15 53 50.7 21.8 " 20.24063 12 32 06.12 -15 53 47.7 21.8 " 20.98853 12 30 52.37 -15 47 57.6 22.4 Allen 20.99170 12 30 52.04 -15 47 56.2 " 20.99492 12 30 51.72 -15 47 54.9 " 20.99810 12 30 51.41 -15 47 53.4 " 21.00127 12 30 51.10 -15 47 52.0 " 21.14904 12 30 36.26 -15 46 56.5 21.7 Bressi 21.16270 12 30 34.74 -15 46 50.4 " 21.17639 12 30 33.37 -15 46 43.8 " 21.98907 12 29 12.94 -15 40 13.9 22.3 Allen 21.99225 12 29 12.63 -15 40 12.2 " 21.99547 12 29 12.29 -15 40 10.7 " 21.99876 12 29 11.95 -15 40 09.1 " 22.00191 12 29 11.63 -15 40 07.8 " 連結軌道要素、位置推算表は次のとおり、 Orbital elements: P/2004 R1 (McNaught) Epoch 2004 Aug. 23.0 TT = JDT 2453240.5 T 2004 Aug. 30.20469 TT MPCW q 0.9884388 (2000.0) P Q n 0.17991978 Peri. 0.59667 +0.44787611 +0.89080784 a 3.1075403 Node 296.01301 -0.82066939 +0.37558012 e 0.6819225 Incl. 4.88987 -0.35483622 +0.25573615 P 5.48 From 59 observations 2004 Sept. 2-2015 Apr. 22, mean residual 0".5. P/2004 R1 (McNaught) Epoch 2010 Feb. 13.0 TT = JDT 2455240.5 T 2010 Feb. 21.13145 TT MPCW q 0.9856526 (2000.0) P Q n 0.18018738 Peri. 0.68337 +0.44854538 +0.89046411 a 3.1044629 Node 295.96953 -0.82041297 +0.37617663 e 0.6825046 Incl. 4.89320 -0.35458371 +0.25605626 P 5.47 From 59 observations 2004 Sept. 2-2015 Apr. 22, mean residual 0".5. P/2004 R1 (McNaught) Epoch 2015 Aug. 6.0 TT = JDT 2457240.5 T 2015 Aug. 7.31079 TT MPCW q 0.9770129 (2000.0) P Q n 0.18082521 Peri. 0.74283 +0.44915236 +0.89014815 a 3.0971582 Node 295.94922 -0.82016894 +0.37668917 e 0.6845454 Incl. 4.89973 -0.35437984 +0.25640112 P 5.45 From 59 observations 2004 Sept. 2-2015 Apr. 22, mean residual 0".5. P/2004 R1 (McNaught) Epoch 2021 Jan. 26.0 TT = JDT 2459240.5 T 2021 Jan. 17.14219 TT MPCW q 0.9722801 (2000.0) P Q n 0.18109147 Peri. 0.77629 +0.44937308 +0.89002328 a 3.0941216 Node 295.93004 -0.82008774 +0.37682597 e 0.6857654 Incl. 4.90890 -0.35428791 +0.25663349 P 5.44 From 59 observations 2004 Sept. 2-2015 Apr. 22, mean residual 0".5. P/2004 R1 (McNaught) Epoch 2015 June 27.0 TT = JDT 2457200.5 T 2015 Aug. 7.31053 TT MPCW q 0.9770175 (2000.0) P Q n 0.18087467 Peri. 0.74183 +0.44913887 +0.89015493 a 3.0965937 Node 295.94934 -0.82017457 +0.37667654 e 0.6844864 Incl. 4.89976 -0.35438389 +0.25639613 P 5.45 From 59 observations 2004 Sept. 2-2015 Apr. 22, mean residual 0".5. Ephemeris: P/2004 R1 (McNaught) Date TT R. A. (2000) Decl. Delta r Elong. Phase m1 2015 03 23 13 10 26.5 -17 28 47 1.0219 1.9781 157.1 11.3 23.5 ... 2015 04 07 12 52 53.5 -17 07 21 0.8507 1.8433 169.2 5.8 22.8 ... 2015 04 15 12 40 40.9 -16 28 56 0.7806 1.7705 165.9 7.9 22.4 ... 2015 04 21 12 30 50.7 -15 47 57 0.7377 1.7156 159.6 11.8 22.2 2015 04 22 12 29 11.4 -15 40 13 0.7314 1.7065 158.4 12.5 22.1 2015 04 23 12 27 32.1 -15 32 15 0.7252 1.6973 157.2 13.3 22.1 ... 2015 04 29 12 17 47.4 -14 40 22 0.6925 1.6422 149.7 18.0 21.9 ... 2015 05 07 12 05 55.6 -13 24 13 0.6589 1.5689 139.4 24.7 21.6 ... 2015 05 22 11 50 22.3 -11 05 53 0.6173 1.4327 121.2 37.2 21.0 (CBET 4094、MPEC 2015-H86)