C/1955 N1 (Bakharev–Macfarlane–Krienke)

Comet Bakharev–Macfarlane–Krienke, formally designated as C/1955 N1, is a non-periodic comet that was observed from July to November 1955. It was discovered independently by three astronomers, Anatoly M. Bakharev, Lewis Macfarlane and Ora “Karl” Krienke, Jr.

C/1955 N1
(Bakharev–Macfarlane–Krienke)

Comet B–M–K photographed by Paolo Maffei from Italy on 25 July 1955.[1]
Discovery[2][3]
Discovered by	Anatoly M. Bakharev Lewis Macfarlane[4] Ora “Karl” Krienke, Jr.[4]
Discovery site	Stalinabad, Tajik SSR Seattle, USA
Discovery date	13–14 July 1955
Designations
Alternative designations	1955 IV, 1955f[5]
Orbital characteristics[6]
Epoch	16 August 1955 (JD 2435335.5)
Observation arc	132 days
Number of observations	28
Aphelion	~500 AU
Perihelion	1.427 AU
Semi-major axis	~250 AU
Eccentricity	0.99425
Orbital period	~3,900 years
Inclination	50.034°
Longitude of ascending node	303.47°
Argument of periapsis	13.216°
Mean anomaly	0.009°
Last perihelion	11 July 1955
TJupiter	0.879
Earth MOID	0.426 AU
Jupiter MOID	3.195 AU
Physical characteristics[7][8]
Spectral type	(B–V) = +0.67 (U–B) = –0.52
Comet total magnitude (M1)	4.79
Apparent magnitude	7.8 (1955 apparition)

Observational history

The comet was already on its outbound trajectory when it was first discovered by Anatoly M. Bakharev on the night of 13 July 1955.^[2] It was independently discovered by Lewis Macfarlane and Ora "Karl" Krienke, Jr about 17 hours later on 14 July 1955, where they immediately found out that their comet is the same object as Bakharev's earlier find.^[3] At the time, the comet was an 8th-magnitude object within the constellation Pegasus.^[a]

Between 17 and 22 July 1955, Kenneth M. Yoss made the first spectroscopic observations of the comet using the 24–36 inch Schmidt telescope at the University of Michigan, where he measured the gas emissions within its coma and compared it with that of 24P/Schaumasse, C/1953 T1 (Abell), and C/1955 L1 (Mrkos).^[9] Eric Mervyn Lindsay captured 14 photographic plates of the comet between 15 July and 12 August 1955.^[10] Photoelectric observations were also conducted at the Mount Wilson Observatory between 28 July and 2 August 1955, obtaining its color indices.^[7]

The comet was last seen on 25 November 1955 by Elizabeth Roemer as a 17th-magnitude object within the constellation Cepheus.^[b] She and Hamilton Jeffers later attempted to find the comet between February and March 1956 but they failed to locate it.^[8]