Electronic Telegram No. 5749 Central Bureau for Astronomical Telegrams Mailing address: Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network COMET P/2013 T2 (SCHWARTZ) R. Weryk, Department of Physics and Astronomy, University of Western Ontario, accidentally recovered comet P/2013 T2 (cf. CBET 3676) in images obtained on July 25 with the Pan-STARRS2 1.8-m Ritchey-Chretien reflector at Haleakala, Hawaii. Four stacked 45-s w-band survey images taken in 1".0 seeing show a condensed head of size 1".7 (full-width-at-half-maximum) with a tail about 8" long toward p.a. 240 degrees. Weryk was able to identify pre-recovery images obtained on June 27 with the Pan-STARRS1 1.8-m reflector at Haleakala, when four 45-s w-band survey images taken in 1".5-2".0 seeing showed a diffuse head of size about 2".1 (FWHM) and a tail about 6" long toward p.a. 240 deg. Weryk also identified the comet with only "a very marginal appearance" on Pan-STARRS2 images obtained on Sept. 16. His available astrometry is tabulated below. 2026 UT R.A. (2000) Decl. Mag. June 27.58673 1 44 33.93 + 9 54 22.9 21.1 27.59130 1 44 34.50 + 9 54 27.7 20.5 27.59588 1 44 35.10 + 9 54 32.3 21.0 27.60045 1 44 35.67 + 9 54 37.1 21.5 July 25.60633 2 41 02.54 +17 15 12.3 21.7 25.61013 2 41 02.96 +17 15 15.5 21.2 25.61396 2 41 03.38 +17 15 18.9 21.3 25.61778 2 41 03.80 +17 15 22.0 21.2 Sept.16.53591 3 53 42.43 +27 50 37.7 21.3 16.54620 3 53 42.79 +27 50 43.9 21.6 The residuals for the recovery observations in 2026 are +11'.0 in R.A. and +7'.1 in Decl. from the prediction in NK 3212 (and in the ICQ's Comet Handbook 2026), with a corresponding correction of Delta(T) = -0.54 day. The following linked orbital elements by S. Nakano (Central Bureau) are from 124 observations spanning 2013 Sept. 14-2026 Sept. 16 (mean residual 0".5). The comet passed 0.99 AU from Jupiter on 2015 Oct. 6 and 0.27 AU from Jupiter on 2004 June 7 UT. Epoch = 2000 Feb. 26.0 TT T = 2000 Feb. 15.07580 TT Peri. = 325.85295 e = 0.4470331 Node = 12.54786 2000.0 q = 2.0601953 AU Incl. = 7.06848 a = 3.7257117 AU n = 0.13705353 P = 7.19 years Epoch = 2007 Mar. 1.0 TT T = 2007 Mar. 19.39695 TT Peri. = 342.32263 e = 0.5287693 Node = 2.69721 2000.0 q = 1.5980797 AU Incl. = 9.35655 a = 3.3912897 AU n = 0.15781808 P = 6.24 years Epoch = 2013 July 7.0 TT T = 2013 June 20.65278 TT Peri. = 342.50689 e = 0.5283750 Node = 2.63364 2000.0 q = 1.5996290 AU Incl. = 9.35298 a = 3.3917393 AU n = 0.15778670 P = 6.25 years Epoch = 2019 Nov. 13.0 TT T = 2019 Nov. 30.05179 TT Peri. = 345.44338 e = 0.5009312 Node = 0.82536 2000.0 q = 1.7404876 AU Incl. = 9.45633 a = 3.4874702 AU n = 0.15133463 P = 6.51 years Epoch = 2026 June 9.0 TT T = 2026 June 10.43404 TT Peri. = 345.57613 e = 0.4999525 Node = 0.77794 2000.0 q = 1.7466253 AU Incl. = 9.44761 a = 3.4929187 AU n = 0.15098068 P = 6.53 years Epoch = 2033 Jan. 3.0 TT T = 2032 Dec. 20.78663 TT Peri. = 345.46297 e = 0.4975402 Node = 0.73036 2000.0 q = 1.7595085 AU Incl. = 9.43474 a = 3.5017899 AU n = 0.15040731 P = 6.55 years Epoch = 2039 July 31.0 TT T = 2039 July 15.17441 TT Peri. = 345.50277 e = 0.4963760 Node = 0.70998 2000.0 q = 1.7675139 AU Incl. = 9.42606 a = 3.5095902 AU n = 0.14990616 P = 6.58 years Epoch = 2046 Feb. 24.0 TT T = 2046 Feb. 4.43506 TT Peri. = 345.40674 e = 0.4974097 Node = 0.69919 2000.0 q = 1.7620372 AU Incl. = 9.43419 a = 3.5059119 AU n = 0.15014213 P = 6.56 years The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 17.0 and 2.5n = 10.0 for the magnitudes. The comet appears to be a couple of magnitudes fainter than at its 2013 return. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2026 08 28 03 34.70 +24 24.7 1.473 1.887 97.1 32.1 20.6 2026 09 07 03 45.93 +26 14.1 1.413 1.922 103.8 30.6 20.6 2026 09 17 03 54.00 +27 55.1 1.356 1.960 111.3 28.5 20.6 2026 09 27 03 58.42 +29 27.2 1.305 2.000 119.6 25.8 20.6 2026 10 07 03 58.81 +30 48.4 1.262 2.043 128.8 22.4 20.6 2026 10 17 03 55.03 +31 54.6 1.233 2.088 138.6 18.4 20.7 2026 10 27 03 47.52 +32 41.1 1.220 2.134 148.9 13.9 20.7 2026 11 06 03 37.34 +33 03.5 1.228 2.182 158.8 9.4 20.8 2026 11 16 03 26.09 +33 00.8 1.260 2.231 165.6 6.3 21.0 2026 11 26 03 15.62 +32 37.1 1.317 2.282 163.8 6.9 21.2 2026 12 06 03 07.37 +32 00.1 1.399 2.333 155.7 10.0 21.4 2026 12 16 03 02.22 +31 18.7 1.505 2.385 145.9 13.4 21.7 2026 12 26 03 00.48 +30 40.5 1.631 2.437 136.0 16.3 21.9 The comet was apparently too far south for the surveys at its 2019 return, but the following ephemeris (using the above magnitude parameters) is provided in hopes that some images might be found to show it then. It is possible that the comet was a magnitude or two brighter than what is listed below. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2019 06 06 19 02.37 -38 36.4 1.398 2.323 148.3 13.3 21.4 2019 06 16 18 56.68 -39 29.4 1.304 2.272 156.4 10.3 21.1 2019 06 26 18 48.08 -40 10.3 1.232 2.221 162.0 8.1 20.9 2019 07 06 18 37.59 -40 30.9 1.183 2.172 161.7 8.4 20.7 2019 07 16 18 26.95 -40 26.1 1.156 2.124 155.6 11.4 20.6 2019 07 26 18 18.00 -39 55.6 1.150 2.077 147.1 15.4 20.5 2019 08 05 18 12.30 -39 03.6 1.162 2.032 137.9 19.5 20.4 2019 08 15 18 10.84 -37 56.7 1.190 1.990 129.0 23.3 20.4 2019 08 25 18 13.89 -36 40.8 1.229 1.949 120.7 26.5 20.3 2019 09 04 18 21.26 -35 19.7 1.277 1.911 113.0 29.1 20.3 2019 09 14 18 32.54 -33 54.6 1.332 1.877 105.9 31.0 20.4 2019 09 24 18 47.14 -32 24.9 1.391 1.845 99.5 32.4 20.4 2019 10 04 19 04.50 -30 49.1 1.454 1.817 93.7 33.3 20.4 2019 10 14 19 24.07 -29 05.2 1.519 1.793 88.3 33.8 20.4 2019 10 24 19 45.31 -27 11.4 1.587 1.774 83.4 33.9 20.5 2019 11 03 20 07.79 -25 06.4 1.657 1.758 78.8 33.6 20.5 2019 11 13 20 31.12 -22 49.7 1.730 1.748 74.5 33.1 20.6 2019 11 23 20 54.94 -20 21.4 1.804 1.742 70.4 32.3 20.7 2019 12 03 21 19.03 -17 42.3 1.881 1.741 66.5 31.3 20.8 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2026 CBAT 2026 September 24 (CBET 5749) Daniel W. E. Green