C/1885 X1 (Fabry)

Fabry's Comet, formally designated as C/1885 X1, is a non-periodic comet that became visible to the naked eye on April 1886.^[1] It was the only comet discovered by the French astronomer, Louis Fabry.

C/1885 X1 (Fabry)

Engraving of the positions of Fabry's Comet over the horizon of Paris, France in April 1886.[1]
Discovery[2]
Discovered by	Louis Fabry
Discovery site	Paris, France
Discovery date	1 December 1885
Designations
Alternative designations	1886 I, 1885d[3]
Orbital characteristics[4][5]
Epoch	18 January 1886 (JD 2409924.5)
Observation arc	142 days
Number of observations	46
Aphelion	~20,600 AU (inbound)
Perihelion	0.642 AU
Semi-major axis	~10,300 AU (inbound)
Eccentricity	0.99994 (inbound) 1.00010 (outbound)
Orbital period	~1.05 million years (inbound)
Inclination	82.630°
Longitude of ascending node	37.962°
Argument of periapsis	126.59°
Mean anomaly	–0.001°
Last perihelion	6 April 1886
Earth MOID	0.181 AU
Jupiter MOID	0.781 AU
Physical characteristics[6]
Comet total magnitude (M1)	5.2
Apparent magnitude	2.0 (1886 apparition)

Observational history

While working at the Paris Observatory on the night of 1 December 1885, Louis Fabry discovered a new comet that was then a 12th-magnitude object within the constellation Pisces.^[a]

Ralph Copeland observed the comet at Dunecht, Scotland and described it as "brighter towards the preceding side" on 7 December 1885.^[7]