C/1997 L1 (Zhu–Balam)

C/1997 L1 (Zhu-Balam)

Discovery
Discovered by	David D. Balam Jin Zhu
Discovery date	3–8 June 1997
Orbital characteristics[1][2]
Epoch	22 August 1997 (JD 2450682.5)
Observation arc	453 days (1.24 years)
Number of observations	213
Aphelion	4,831.23 AU
Perihelion	4.899 AU
Semi-major axis	2,418.07 AU
Eccentricity	0.9979
Orbital period	118,907.85 years
Inclination	72.991°
Longitude of ascending node	233.299°
Argument of periapsis	346.365°
Last perihelion	22 November 1996
TJupiter	0.805
Earth MOID	3.9127 AU
Jupiter MOID	0.4171 AU
Physical characteristics[1][3]
Dimensions	10 km (6.2 mi)
Comet total magnitude (M1)	6.5
Comet nuclear magnitude (M2)	8.5

Comet Zhu–Balam, formally designated C/1997 L1, is a long-period comet first identified by David D. Balam on June 8, 1997, and originally photographed by Jin Zhu on June 3, 1997.^[4][3] The comet is estimated at 10 kilometres in diameter^[3] with a period of approximately 36,895 years.^[2]

Orbit

Given the orbital eccentricity of this object, different epochs can generate quite different heliocentric unperturbed two-body best-fit solutions to the aphelion distance (maximum distance) of this object. For objects at such high eccentricity, the Sun's barycentric coordinates are more stable than heliocentric coordinates. Using JPL Horizons the barycentric orbital elements for epoch 2015-Jan-01 generate a semi-major axis of 1,100 AU and a period of approximately 36,895 years.^[2]

References

1. "C/1997 L1 (Zhu–Balam) – JPL Small-Body Database Lookup". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 11 November 2024.
2. Horizons output. "Barycentric Osculating Orbital Elements for Comet Zhu-Balam (C/1997 L1)". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 31 January 2011. (Solution using the Solar System Barycenter and barycentric coordinates. Select Ephemeris Type:Elements and Center:@0)
3. M. McNeney (6 February 1998). "Sharp-eyed Balam co-discovers comet". The Ring. University of Victoria. Archived from the original on 25 October 2004. Retrieved 1 February 2010.
4. "New comet named after astronomers". Canadian Broadcasting Corporation. November 13, 1998. Retrieved 1 February 2010.