4P/Faye (0004P)

TRY AGAIN 2028

Type: Periodic Perihelion date: 8 September 2021 Perihelion distance (q): 1.6 Aphelion distance (Q) : 6.0 Period (years): 7.5 Eccentricity (e): 0.58 Inclination (i): 8.0 JPL orbit diagram COBS lightcurve Hervé Faye (Royal Observatory, Paris) discovered this comet on 23 November 1843, near Gamma Orionis. The comet exhibited a distinct nucleus, which emitted faint indications of a tail extending 4 arcmin away from the sun. Due to cloudy weather, Faye was not able to confirm his discovery until 25 November. The comet was kept under observation until 10 April 1844 during the discovery apparition, or for more than 4 months. The comet had passed perihelion one month prior to discovery, but was discovered about a day before its closest passage by Earth (0.79 AU). T. Henderson (Edinburgh) became the first to realize this comet was moving in a short- period orbit. Although his initial computed orbital period was 6.58 years, additional observations allowed both John. R. Hind and himself to independently revise the orbit during the next few months. Ultimately, by May, the period had been refined to 7.43 years. As the comet's expected apparition of 1851 approached, astronomers needed as accurate a prediction as possible to guarantee recovery. Urbain Jean Joseph Leverrier undertook this task. He found the comet had passed 0.25 AU from Jupiter during 1841, which acted to decrease the perihelion distance from 1.81 AU to the discovery value of 1.69 AU. He then determined the comet's next perihelion would fall during early April 1851. James Challis (Cambridge, England) recovered the comet very close to Leverrier's predicted position on 28 November 1850. This comet has been seen at every return since its discovery, except for those of 1903 and 1918, which were especially unfavorable. The comet's having been missed during 1903 brought problems for the 1910 return. Initially searches during the 1910 apparition were failing to locate the comet. Interestingly, Cerulli (Teramo, Italy) found a 10th-magnitude comet on 8 November 1910. After observations were obtained for the next two weeks, the first orbital computations revealed this was Faye's periodic comet. Close approaches to planets: • 1.32 AU from Jupiter on 25 October 1993 - decreased perihelion distance from 1.59 AU to 1.66 AU; decreased orbital period from 7.34 to 7.52 years • 0.69 AU from Earth on 30 October 2006 0.63 AU from Jupiter on 7 March 2018 - decreased perihelion distance from 1.66 AU to 1.62 AU; decreased orbital period from 7.51 to 7.48 years • 0.94 AU from Earth on 5 December 2021 0.98 AU from Earth on 8 December 2036 Observations (VEMag = visual equivalent magnitude) Date 10x10 mag Error VEmag Coma ' 25 Oct 14 15.93 0.03 14.3 0.4 02 Nov 14 15.91 0.01 14.3 0.4 09 Nov 14 16.12 0.07 14.1 0.3 16 Nov 14 16.02 0.03 14.8 0.2 24 Nov 14 16.20 0.02 15.2 0.2 01 Dec 14 16.12 0.06 14.7 0.2 16 Dec 14 16.24 0.05 14.4 0.3 23 Dec 14 16.23 0.02 14.2 0.3 30 Dec 14 16.27 0.05 14.8 0.3 14 Jan 15 16.24 0.03 14.6 0.3 21 Jan 15 16.21 0.04 14.2 0.3 28 Jan 15 16.20 0.02 14.4 0.4 08 Feb 15 16.11 0.04 14.2 0.2 16 Feb 15 16.17 0.04 14.4 0.3 11 Mar 15 16.69 0.03 14.9 0.2 18 Mar 15 16.93 0.03 14.8 0.3 08 Apr 15 17.38 0.06 15.0 0.2 19 Apr 15 17.76 0.04 15.8 0.2 21-Aug-21 12.9 0.8 05-Sep-21 12.4 1.5 09-Sep-21 13.57 0.01 10.5 6.4 16-Sep-21 14.15 0.10 12.3 1.7