Nakano Note (Nakano wa Kangaeru noda) NK 2740The Return Comets in 2017 (Missing comets)## 18D/Perrine-Mrkos T = 2017 Feb. 26.28695 TT Epoch = 2017 Feb. 16.0 TT Peri. = 157.02026 e = 0.5838584 Node = 237.95332 (2000.0) a = 3.9561628 AU Inc. = 16.87330 n'= 0.12525436 q = 1.6463240 AU P = 7.869 years From an orbit in NK 573 using 17 observations 1961-1968, mean residual 1".87. Kobayashi gives the predicted T = 2017 Oct. 25 TT from his linked orbit 1955-1968 including A1 = +2.75 and A2 = -0.4689 (2014). D/1952 B1 (Harrington-Wilson) T = 2017 Mar. 1.90185 TT Epoch = 2017 Feb. 16.0 TT Peri. = 0.92616 e = 0.5941134 Node = 118.40543 (2000.0) a = 3.1475690 AU Inc. = 14.39471 n'= 0.17649856 q = 1.2775562 AU P = 5.584 years From an orbit in NK 782 using 176 observations 1994 Mar. 27-June 5, mean residual 3".41. P/1999 XN120 (Catalina) T = 2017 June 12.65965 TT Epoch = 2017 June 16.0 TT Peri. = 162.03735 e = 0.2116063 Node = 285.29256 (2000.0) a = 4.1822172 AU Inc. = 5.02875 n'= 0.11523760 q = 3.2972339 AU P = 8.553 years From an orbit in NK 736 using 72 observations 1999 Nov. 3-2000 Mar. 30, mean residual 0".64. D/1894 F1 (Denning) T = 2017 Aug. 2.44389 TT Epoch = 2017 July 26.0 TT Peri. = 103.20581 e = 0.6415294 Node = 25.61494 (2000.0) a = 4.5279866 AU Inc. = 2.49864 n'= 0.10229311 q = 1.6231499 AU P = 9.635 years From an orbit in NK 782 using 176 observations 1894 Mar. 27-June 5, mean residual 3".41. 5D/Brorsen T = 2017 Sept.19.30034 TT Epoch = 2017 Sept. 4.0 TT Peri. = 19.42137 e = 0.8324914 Node = 96.72594 (2000.0) a = 3.1600705 AU Inc. = 19.85774 n'= 0.17545224 q = 0.5293390 AU P = 5.618 years A1 = +1.323 A2 = +0.13425 From an orbit in NK 946 using 120 observations 1868-1879, mean residual 2".69. Nongravitational parameters A1 = +1.32, A2 = +0.1342. Kobayashi gives the predicted T = 2017 Sept. 18 TT from his linked orbit 1868-1879 (2014).

## Associate of the CBAT

Syuichi Nakano2014 June 25