Comet P/2009 S2 = 2017 M1 (McNaught) K. Sarneczky と R. Konyves-Toth (Konkoly天文台)の通報によると、6月19-20日UT、Konkoly天文台 Piszkesteto Stationの0.60-m Schmidt望遠鏡で得たフィルターなしのCCD露出でP/2009 S2 (IAUC 9075を参照)を検出した。6月19.0日UT、5".0の円形範囲で測定したこの彗星のR-バンド光度は19.9等 であった。 ICQ's 2017 Comet Handbook (p. H13)の中野主一氏の予報に対して、Delta(T)は、-0.06 dayであった。 検出位置は次のとおり、 2017 UT R.A. (2000) Decl. Mag. Observer June 19.01345 20 35 23.37 -12 02 36.7 19.9 Sarneczky 19.02527 20 35 23.30 -12 02 43.5 " 20.01371 20 35 17.11 -12 12 07.1 20.1 " 20.02554 20 35 16.98 -12 12 13.3 20.0 " 連結軌道要素と位置推算表は次のとおり、 Orbital elements: P/2009 S2 (McNaught) Epoch 2009 June 18.0 TT = JDT 2455000.5 T 2009 June 23.64022 TT MPCW q 2.2036380 (2000.0) P Q n 0.11609099 Peri. 230.37511 +0.91102981 +0.07378437 a 4.1616961 Node 121.61344 -0.02664947 +0.99233892 e 0.4704952 Incl. 28.44910 -0.41147842 +0.09909257 P 8.49 From 71 observations 2008 May 30-2017 June 20, mean residual 0".5. P/2009 S2 (McNaught) Epoch 2018 Jan. 2.0 TT = JDT 2458120.5 T 2017 Dec. 20.94591 TT MPCW q 2.2140069 (2000.0) P Q n 0.11570769 Peri. 230.39333 +0.91111484 +0.07431208 a 4.1708819 Node 121.57373 -0.02697066 +0.99225296 e 0.4691754 Incl. 28.41389 -0.41126917 +0.09955795 P 8.52 From 71 observations 2008 May 30-2017 June 20, mean residual 0".5. P/2009 S2 (McNaught) Epoch 2026 July 19.0 TT = JDT 2461240.5 T 2026 July 1.39954 TT MPCW q 2.2117883 (2000.0) P Q n 0.11576637 Peri. 230.52518 +0.91092206 +0.07417200 a 4.1694723 Node 121.45677 -0.02639970 +0.99217025 e 0.4695280 Incl. 28.41014 -0.41173299 +0.10048239 P 8.51 From 71 observations 2008 May 30-2017 June 20, mean residual 0".5. P/2009 S2 (McNaught) Epoch 2017 Sept. 4.0 TT = JDT 2458000.5 T 2017 Dec. 20.95329 TT MPCW q 2.2140027 (2000.0) P Q n 0.11573169 Peri. 230.39458 +0.91111616 +0.07426862 a 4.1703054 Node 121.57493 -0.02693009 +0.99225604 e 0.4691030 Incl. 28.41468 -0.41126891 +0.09955965 P 8.52 From 71 observations 2008 May 30-2017 June 20, mean residual 0".5. Ephemeris: P/2009 S2 (McNaught) Date TT R. A. (2000) Decl. Delta r Elong. Phase m1 2017 05 21 20 28 54.7 -09 09 41 2.1941 2.7428 112.3 20.0 20.6 ... 2017 06 05 20 34 27.9 -10 15 54 1.9622 2.6821 125.5 17.9 20.2 ... 2017 06 13 20 35 31.8 -11 10 54 1.8503 2.6505 133.1 16.2 20.1 ... 2017 06 19 20 35 23.4 -12 02 25 1.7732 2.6272 139.1 14.7 19.9 2017 06 20 20 35 17.1 -12 11 54 1.7609 2.6233 140.2 14.4 19.9 2017 06 21 20 35 09.5 -12 21 38 1.7489 2.6195 141.2 14.1 19.9 ... 2017 06 27 20 33 54.3 -13 25 33 1.6810 2.5967 147.5 12.1 19.8 ... 2017 07 05 20 30 58.8 -15 05 02 1.6030 2.5669 156.3 9.1 19.6 ... 2017 07 20 20 22 11.2 -18 48 44 1.5004 2.5131 173.8 2.5 19.4 (CBET 4404、MPEC 2017-M28)