Electronic Telegram No. 5708 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/2026 M4 = P/2006 HR_30 (SIDING SPRING) R. Weryk, Department of Physics and Astronomy, University of Western Ontario, reports the accidental recovery of comet P/2006 HR_30 (cf. IAUCs 8735, 8737) as an object of stellar appearance in images obtained with the Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala, Hawaii (recovery observations tabulated below). Four 45-s w-band survey images taken in 1".5 seeing on June 16 show no coma and no tail, as do two 45-s and two 60-s w-band survey images taken on June 21 in 1".4-1".6 seeing. 2026 UT R.A. (2000) Decl. Mag. June 16.48921 19 32 05.17 -38 25 16.8 20.6 16.49591 19 32 04.94 -38 25 17.4 20.6 16.50248 19 32 04.73 -38 25 17.8 20.6 16.50902 19 32 04.51 -38 25 18.4 20.6 21.46343 19 29 19.12 -38 31 06.1 20.5 21.47001 19 29 18.90 -38 31 06.5 20.6 21.51821 19 29 17.20 -38 31 09.5 20.6 21.51886 19 29 17.18 -38 31 09.7 20.6 The residuals for the recovery observations are +12" in R.A. and +8" in Decl. from the prediction on NK 1640, with a corresponding correction of Delta(T) = -0.12 day. The following linked orbital elements by S. Nakano (Central Bureau) are from 3056 observations spanning 1986 Mar. 5-2026 June 21 (mean residual 0".4). There are no close approaches to major planets during 1970-2026. Epoch = 1985 Feb. 24.0 TT T = 1985 Mar. 2.54491 TT Peri. = 117.20928 e = 0.8430767 Node = 310.19429 2000.0 q = 1.2242456 AU Incl. = 31.85000 a = 7.8015518 AU n = 0.04523062 P = 21.79 years Epoch = 2007 Jan. 20.0 TT T = 2007 Jan. 2.28119 TT Peri. = 117.41382 e = 0.8431412 Node = 309.95124 2000.0 q = 1.2264311 AU Incl. = 31.88456 a = 7.8186946 AU n = 0.04508195 P = 21.86 years Epoch = 2028 Sept.26.0 TT T = 2028 Oct. 9.68810 TT Peri. = 117.59522 e = 0.8431567 Node = 309.65361 2000.0 q = 1.2212805 AU Incl. = 31.95522 a = 7.7866302 AU n = 0.04536070 P = 21.73 years Epoch = 2050 June 3.0 TT T = 2050 June 1.19538 TT Peri. = 117.93412 e = 0.8428176 Node = 309.29560 2000.0 q = 1.2185334 AU Incl. = 32.06867 a = 7.7523522 AU n = 0.04566188 P = 21.58 years The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 11.5 and 2.5n = 6 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2026 06 09 19 35.87 -38 15.0 6.588 7.440 144.8 4.5 20.8 2026 06 19 19 30.71 -38 28.3 6.462 7.386 153.6 3.5 20.8 2026 06 29 19 24.82 -38 38.0 6.364 7.331 160.7 2.6 20.7 2026 07 09 19 18.47 -38 42.8 6.294 7.275 163.6 2.3 20.7 2026 07 19 19 11.95 -38 42.0 6.255 7.220 160.3 2.7 20.6 2026 07 29 19 05.62 -38 35.2 6.245 7.164 152.9 3.7 20.6 2026 08 08 18 59.79 -38 22.6 6.263 7.107 143.9 4.8 20.6 2026 08 18 18 54.73 -38 04.7 6.306 7.050 134.3 5.9 20.6 2026 08 28 18 50.68 -37 42.6 6.370 6.993 124.6 6.8 20.6 2026 09 07 18 47.78 -37 17.1 6.451 6.935 114.9 7.6 20.6 2026 09 17 18 46.12 -36 49.4 6.544 6.877 105.3 8.1 20.6 2026 09 27 18 45.72 -36 20.3 6.645 6.819 95.7 8.4 20.6 2026 10 07 18 46.55 -35 50.5 6.749 6.760 86.4 8.5 20.6 2026 10 17 18 48.54 -35 20.5 6.851 6.700 77.2 8.3 20.6 2026 10 27 18 51.62 -34 50.7 6.947 6.641 68.1 8.0 20.6 2026 11 06 18 55.67 -34 21.1 7.033 6.580 59.2 7.4 20.6 2026 11 16 19 00.58 -33 51.9 7.105 6.520 50.4 6.7 20.6 2026 11 26 19 06.24 -33 23.0 7.160 6.458 41.8 5.8 20.6 2026 12 06 19 12.52 -32 54.4 7.196 6.397 33.4 4.9 20.6 2027 02 24 20 11.71 -29 13.0 6.646 5.886 37.0 5.8 20.2 2027 03 06 20 18.59 -28 48.4 6.476 5.820 45.2 6.9 20.1 2027 03 16 20 25.00 -28 25.6 6.289 5.754 53.6 8.0 20.1 2027 03 26 20 30.81 -28 04.9 6.086 5.686 62.0 8.9 20.0 2027 04 05 20 35.91 -27 46.9 5.872 5.619 70.6 9.7 19.8 2027 04 15 20 40.17 -27 32.0 5.648 5.550 79.3 10.2 19.7 2027 04 25 20 43.46 -27 20.7 5.420 5.482 88.2 10.6 19.6 2027 05 05 20 45.65 -27 13.4 5.191 5.412 97.3 10.7 19.5 2027 05 15 20 46.59 -27 10.1 4.964 5.342 106.6 10.4 19.3 2027 05 25 20 46.16 -27 11.0 4.745 5.271 116.2 9.9 19.2 2027 06 04 20 44.27 -27 15.6 4.538 5.200 126.1 9.1 19.1 2027 06 14 20 40.84 -27 23.3 4.347 5.128 136.2 7.9 19.0 2027 06 24 20 35.90 -27 32.7 4.177 5.056 146.6 6.4 18.8 2027 07 04 20 29.56 -27 42.4 4.031 4.983 157.0 4.6 18.7 2027 07 14 20 22.04 -27 50.2 3.913 4.909 166.9 2.7 18.6 2027 07 24 20 13.71 -27 54.3 3.826 4.834 172.1 1.7 18.5 2027 08 03 20 05.03 -27 53.1 3.770 4.759 165.5 3.1 18.4 2027 08 13 19 56.54 -27 45.4 3.745 4.683 155.1 5.2 18.4 2027 08 23 19 48.78 -27 31.0 3.748 4.607 144.3 7.4 18.3 2027 09 02 19 42.19 -27 10.3 3.776 4.530 133.5 9.3 18.3 2027 09 12 19 37.12 -26 44.2 3.825 4.452 122.8 11.0 18.3 2027 09 22 19 33.80 -26 13.6 3.889 4.373 112.5 12.2 18.3 2027 10 02 19 32.30 -25 39.5 3.964 4.294 102.5 13.2 18.3 2027 10 12 19 32.63 -25 02.6 4.044 4.213 92.8 13.7 18.3 2027 10 22 19 34.69 -24 23.2 4.125 4.132 83.5 13.8 18.3 2027 11 01 19 38.37 -23 41.3 4.202 4.051 74.5 13.7 18.3 2027 11 11 19 43.54 -22 56.8 4.271 3.968 65.7 13.2 18.2 2027 11 21 19 50.01 -22 09.4 4.329 3.885 57.3 12.4 18.2 2027 12 01 19 57.64 -21 18.6 4.373 3.801 49.1 11.3 18.2 2027 12 11 20 06.30 -20 23.9 4.401 3.716 41.1 10.0 18.1 2027 12 21 20 15.83 -19 24.7 4.411 3.630 33.3 8.6 18.1 2028 03 30 22 18.41 -03 38.1 3.483 2.724 34.8 12.1 16.8 2028 04 09 22 32.26 -01 15.4 3.307 2.629 40.6 14.4 16.6 2028 04 19 22 46.39 +01 19.7 3.124 2.533 46.1 16.6 16.4 2028 04 29 23 00.86 +04 08.4 2.934 2.437 51.5 18.9 16.2 2028 05 09 23 15.74 +07 12.7 2.741 2.341 56.5 21.1 15.9 2028 05 19 23 31.18 +10 34.6 2.547 2.244 61.3 23.3 15.6 2028 05 29 23 47.36 +14 16.7 2.356 2.148 65.7 25.5 15.4 2028 06 08 00 04.56 +18 21.6 2.169 2.051 69.7 27.7 15.1 2028 06 18 00 23.16 +22 51.9 1.990 1.956 73.2 29.8 14.7 2028 06 28 00 43.77 +27 49.8 1.822 1.861 76.1 32.0 14.4 2028 07 08 01 07.26 +33 15.2 1.668 1.769 78.3 34.3 14.1 2028 07 18 01 35.02 +39 04.7 1.530 1.678 79.7 36.6 13.8 2028 07 28 02 09.14 +45 07.7 1.412 1.592 80.1 38.9 13.5 2028 08 07 02 52.67 +51 01.9 1.315 1.511 79.7 41.3 13.2 2028 08 17 03 49.30 +56 08.2 1.241 1.435 78.4 43.7 12.9 2028 08 27 05 00.50 +59 31.4 1.187 1.368 76.6 45.9 12.7 2028 09 06 06 20.27 +60 19.4 1.152 1.312 74.4 47.8 12.5 2028 09 16 07 35.22 +58 23.3 1.132 1.267 72.5 49.2 12.4 2028 09 26 08 35.76 +54 24.1 1.122 1.237 71.0 50.0 12.3 2028 10 06 09 21.21 +49 15.1 1.117 1.222 70.3 50.3 12.3 2028 10 16 09 54.91 +43 35.5 1.115 1.225 70.6 50.2 12.3 2028 10 26 10 20.08 +37 48.0 1.110 1.243 72.2 49.6 12.3 2028 11 05 10 38.92 +32 04.1 1.101 1.277 75.0 48.6 12.3 2028 11 15 10 52.75 +26 29.3 1.088 1.325 79.1 47.1 12.4 2028 11 25 11 02.14 +21 06.4 1.069 1.385 84.6 45.2 12.5 2028 12 05 11 07.23 +15 55.9 1.047 1.454 91.3 42.6 12.6 2028 12 15 11 07.91 +10 58.7 1.024 1.531 99.3 39.4 12.7 2028 12 25 11 03.89 +06 16.9 1.003 1.614 108.7 35.3 12.8 2029 01 04 10 55.04 +01 54.9 0.991 1.702 119.1 30.3 12.9 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2026 CBAT 2026 June 29 (CBET 5708) Daniel W. E. Green