Electronic Telegram No. 1913 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://www.cfa.harvard.edu/iau/cbat.html COMET P/2009 L18 (SKIFF) G. Sostero, E. Guido, P. Camilleri and E. Prosperi report the recovery of comet P/2002 S1 (cf. IAUC 7972) from the coaddition of 40 unfiltered 60-s CCD exposures obtained remotely on June 15.6 UT with the 0.35-m f/7 reflector at the Skylive-Grove Creek Observatory (near Trunkey, NSW, Australia). The recovery was confirmed from the coaddition of 10 unfiltered 300-s exposures with the same equipment on Aug. 18.6. The object was of stellar appearance on each occasion. Packed desig. Date UT R.A. (2000.0) Decl. Mag. Obs PK09L180 C2009 06 15.60811 20 49 13.30 -49 02 32.4 20.0 E16 PK09L180 C2009 06 15.60893 20 49 13.28 -49 02 32.7 20.4 E16 PK09L180 C2009 06 15.62322 20 49 12.86 -49 02 36.8 20.6 E16 PK09L180 C2009 06 15.63989 20 49 12.36 -49 02 41.8 20.2 E16 PK09L180 C2009 06 15.64617 20 49 12.12 -49 02 43.5 20.2 E16 PK09L180 C2009 08 18.57587 19 45 30.32 -48 51 00.9 19.6 E16 PK09L180 C2009 08 18.58151 19 45 30.07 -48 50 58.5 19.5 E16 PK09L180 C2009 08 18.58717 19 45 29.80 -48 50 56.0 19.6 E16 PK09L180 C2009 08 18.60932 19 45 28.60 -48 50 46.1 19.9 E16 PK09L180 C2009 08 18.63158 19 45 27.38 -48 50 36.1 19.7 E16 PK09L180 C2009 08 18.63714 19 45 27.13 -48 50 33.7 19.9 E16 PK09L180 C2009 08 18.64270 19 45 26.82 -48 50 31.4 19.8 E16 The indicated corrections to the predictions on MPC 59600 and in the 2009/2009 Comet Handbook are Delta(T) = -0.16 and -0.19 day, respectively. On MPC 46839 (and MPEC 2002-W08) the prediscovery observations on 2001 July 27, Aug. 1 and Aug. 9 were incorrectly specified as having been made at Haleakala (observatory code 608) instead of at Palomar (observatory code 644). The following additional prediscovery observations have been identified: Packed desig. Date UT R.A. (2000.0) Decl. Mag. Obs PK02S010 C2001 08 22.21978 21 49 04.82 -34 06 56.9 19.5 644 PK02S010 C2001 08 22.23141 21 49 03.90 -34 06 53.4 19.8 644 PK02S010 C2001 08 22.24183 21 49 03.15 -34 06 51.3 20.1 644 The following improved orbital elements satisfy 149 observations 2001-2009 with mean residual 0".6: P/2002 S1 = 2009 L18 (Skiff) Epoch 2002 Mar. 27.0 TT = JDT 2452360.5 T 2002 Mar. 25.20326 TT MPC q 2.3054124 (2000.0) P Q n 0.12144316 Peri. 35.42237 +0.90732245 -0.40800327 a 4.0385055 Node 347.38429 +0.18908842 +0.61158867 e 0.4291422 Incl. 27.68784 +0.37551503 +0.67785886 P 8.12 Epoch 2010 Sept. 1.0 TT = JDT 2455440.5 T 2010 Aug. 14.52148 TT MPC q 2.4200724 (2000.0) P Q n 0.11657951 Peri. 37.84797 +0.89340164 -0.43713353 a 4.1500619 Node 346.82499 +0.21199967 +0.61365938 e 0.4168587 Incl. 27.05507 +0.39609297 +0.65752296 P 8.45 Residuals in seconds of arc K017R 644 0.4- 0.3- K02AE 360 0.1+ 0.4- K02CD 360 0.7+ 0.1+ K017R 644 0.1- 0.2- K02AJ J95 0.3+ 0.2+ K02CD 360 0.7+ 0.2- K017R 644 0.4- 0.1- K02AJ J95 0.7+ 0.2- K02CH 785 (2.8- 4.4-) K0181 644 0.1- 0.3- K02B1 170 0.4- 1.0+ K02CH 785 1.4- 0.3+ K0181 644 0.8+ 0.2- K02B1 170 1.8- 0.1+ K02CR 704 0.1- 1.8+ K0181 644 0.6+ 0.1- K02B3 349 0.4+ 0.4- K02CR 704 1.5- 0.6- K0189 644 0.0 0.1+ K02B3 349 0.9- 1.0- K02CR 704 1.3- 1.4- K0189 644 0.0 0.3+ K02B3 349 0.6- 0.4- K02CR 360 0.3+ 0.1- K0189 644 0.3+ 0.2+ K02B3 349 0.8+ 0.4- K02CR 360 0.3+ 0.1- K018M 644 0.1- 0.0 K02B4 J95 0.4+ 0.0 K02CS 349 1.8+ 0.0 K018M 644 0.6- 0.3+ K02B5 785 0.4- 0.9- K02CS 349 0.3+ 0.3+ K018M 644 0.2- 0.6- K02B5 785 1.0+ 0.1- K02CS 349 1.5- 0.3- K01A8 644 0.6- 0.2+ K02B5 360 0.1- 0.0 K02CT 213 (2.2- 1.9-) K01A8 644 0.3- 1.1+ K02B5 360 0.7- 0.0 K0317 360 0.7+ 0.1+ K01A8 644 0.1+ 1.5+ K02B7 J95 0.4+ 0.4- K0317 360 0.6+ 0.2- K029H 699 0.8- 0.5- K02B7 J95 0.3- 0.2- K0318 699 (2.5- 2.1-) K029H 699 0.7- 0.3+ K02B7 J95 1.3- 0.1+ K0318 699 0.5+ 0.5- K029H 699 1.7- 0.3- K02B7 785 0.6+ 0.5- K0318 699 0.0 1.6- K029H 699 0.6- 0.5+ K02B7 785 (2.3- 1.3-) K0318 699 (1.5- 2.0-) K029I 711 0.1+ 0.2+ K02B9 118 0.3- 0.1- K031A H43 (5.3+ 5.3+) K029I 711 0.7- 0.2+ K02B9 118 0.1+ 0.1- K031A H43 (1.6+ 2.7+) K029I 711 0.8- 0.2+ K02B9 118 0.1+ 0.2+ K031A H43 (1.4- 5.5+) K029J 711 0.6- 0.6+ K02B9 349 0.8- 1.1- K031B H41 0.1+ 0.2- K029J 711 0.3- 0.6+ K02B9 349 0.5- 1.5- K031C 561 1.6+ 0.7+ K029J 711 0.5- 0.5+ K02B9 349 0.6+ 1.2- K031C 561 0.8+ 0.6+ K029K 711 0.9- 0.3+ K02BA 561 0.4+ 0.1+ K031C 561 0.7+ 0.1+ K029K 711 0.4- 0.2+ K02BA 561 0.6- 0.0 K031C 561 0.7+ 0.3+ K029K 711 0.3- 0.3+ K02BA 561 0.2- 0.0 K031O H43 (4.2- 4.0-) K029P J95 0.7+ 0.3- K02BC 360 0.2+ 0.5- K031O H43 1.2- 0.4+ K029P J95 0.6+ 0.4+ K02BC 360 0.2- 0.5- K031P 587 0.2+ 1.3- K029P J95 0.7- 0.1+ K02BD 704 0.1+ 0.1+ K031P 587 1.0+ 0.8- K029P J95 0.2- 0.3- K02BD 704 0.3- 0.3- K031R H43 (2.2- 0.8-) K029T 468 0.7- 0.2- K02BD 704 0.9- 1.1- K0321 H41 (0.6+ 2.0-) K029T 468 0.3+ 0.4- K02BD 704 0.3- 0.3- K0321 H41 (4.1+ 2.1+) K029T 468 0.8- 0.1- K02BD 704 1.7- 0.2- K0322 360 0.9+ 0.8- K029T 468 0.3+ 0.1- K02BE 785 (3.1- 0.5-) K0322 360 0.1- 0.8- K029T 468 0.5- 0.1- K02BE 785 (2.2- 1.7-) K032Q 118 1.3+ 0.5- K029T 468 0.3+ 0.1+ K02BE 785 0.3- 1.5- K032Q 118 1.7+ 1.3- K029U 118 0.2- 0.6+ K02BH 704 0.0 0.2+ K032Q 118 (1.2+ 2.3-) K029U 118 0.4- 0.7+ K02BH 704 0.1+ 0.8+ K0346 J95 0.8+ 0.4+ K029U 118 0.4- 0.1+ K02BH 704 0.7- 0.3- K0346 J95 0.7- 0.2+ K029U 118 0.1- 0.8+ K02BH 704 0.5- 0.2+ K0347 J95 0.7+ 0.5- K02A4 J95 0.2+ 0.6+ K02BH 704 1.3+ 0.8+ K096F E16 0.8+ 0.6- K02A4 J95 0.4- 0.1+ K02BQ 349 0.6- 0.2+ K096F E16 0.8+ 0.6- K02A4 J95 0.3+ 0.0 K02BQ 349 0.9+ 1.5- K096F E16 0.8+ 0.6- K02A4 J95 0.2- 0.1+ K02BQ 349 0.9- 0.3- K096F E16 0.7+ 0.8- K02A4 J95 (2.8- 0.3-) K02BS J95 (2.7+ 0.2-) K096F E16 0.1+ 0.7- K02A9 118 0.2- 0.2+ K02C5 J95 0.1- 0.5+ K098I E16 0.5- 1.0- K02A9 118 0.2+ 0.3+ K02C5 J95 0.2- 1.4+ K098I E16 0.0 1.0- K02A9 118 0.1+ 0.3+ K02C9 118 0.9+ 0.2+ K098I E16 0.3+ 0.9- K02A9 118 0.0 0.2+ K02C9 118 0.8+ 0.3- K098I E16 0.2+ 0.4- K02A9 118 0.4+ 0.1- K02C9 118 0.5+ 0.3- K098I E16 0.1- 0.1+ K02AD 204 1.1- 0.6- K02CA 118 0.1+ 0.1- K098I E16 0.3+ 0.2+ K02AD 204 0.9- 0.4- K02CA 118 0.5+ 0.2+ K098I E16 0.2+ 0.1+ K02AD 204 0.9- 0.4- K02CA 118 0.2+ 0.3- K02AE 360 0.0 0.4- K02CA 118 0.0 0.2- The following ephemeris assumes H_10 = 12.0: Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2009 08 17 19 46.91 -49 01.7 2.574 3.385 136.9 11.8 19.3 2009 08 27 19 39.17 -47 46.4 2.616 3.346 129.1 13.6 19.3 2009 09 06 19 34.35 -46 17.0 2.675 3.307 120.9 15.2 19.3 2009 09 16 19 32.58 -44 38.4 2.749 3.269 112.5 16.5 19.3 2009 09 26 19 33.72 -42 54.5 2.834 3.230 104.2 17.5 19.4 2009 10 06 19 37.51 -41 08.1 2.927 3.192 96.1 18.1 19.4 2009 10 16 19 43.60 -39 20.7 3.023 3.154 88.2 18.4 19.4 2009 10 26 19 51.65 -37 32.9 3.121 3.116 80.6 18.3 19.4 2009 11 05 20 01.33 -35 44.7 3.216 3.079 73.1 18.0 19.4 2009 11 15 20 12.36 -33 55.6 3.308 3.042 65.9 17.3 19.4 2009 11 25 20 24.49 -32 05.1 3.394 3.005 58.9 16.3 19.4 2009 12 05 20 37.48 -30 12.6 3.471 2.969 52.0 15.2 19.4 2009 12 15 20 51.15 -28 17.4 3.540 2.933 45.4 13.8 19.4 2009 12 25 21 05.35 -26 19.0 3.597 2.898 38.8 12.3 19.4 2010 01 04 21 19.94 -24 17.1 3.644 2.863 32.5 10.6 19.4 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2009 CBAT 2009 August 18 (CBET 1913) Brian G. Marsden