207P/NEAT (0207P)

Type: Periodic Perihelion date: 31 January 2024 Perihelion distance (q): 0.9 Aphelion distance (Q) : 6.8 Period (years): 7.7 Eccentricity (e): 0.76 Inclination (i): 10.2 JPL orbit diagram COBS lightcurve 207P/NEAT = 2001 J1 = 2008 T5 S. Pravdo, E. Helin, and K. Lawrence, Jet Propulsion Laboratory, reported the discovery of a 17th mag comet by NEAT on CCD images taken with the 1.2-m reflector at Haleakala on 11 May 2001. The comet is possibly the long-lost 3D/Biela, but this is felt unlikely. Observations suggest a moderately close approach to Jupiter (0.8 AU) in 1972, before which the P/2001 J1 perihelion distance was 0.96 AU and the inclination 11 degrees. While there was tolerably good agreement in orbital eccentricity, argument of perihelion and nodal longitude, it is difficult to reconcile the perihelion distance and inclination with the 3D/Biela values. To get these elements to agree would require the nongravitational forces to act in some special way, together with the gravitational effects of occasional approaches to Jupiter. Ken-ichi Kadota, Ageo, Saitama-ken, Japan recovered the comet on 15 October 2008. Confirming observations were also made by H. Abe (Yatsuka-cho, Shimane- ken, Japan, 0.26-m reflector). Observations (VEMag = visual equivalent magnitude) Date 10x10 mag Error VEmag Coma ' 11-Nov-23 19.9 0.4 17-Nov-23 19.3 0.4