94P/Russell

For other comets of the same name, see Comet Russell.

94P/Russell 4

Comet Russell 4 imaged by Kevin Heider on 19 February 2010 while it was 2.2 AU from the Sun.
Discovery
Discovered by	Kenneth S. Russell
Discovery date	7 March 1984
Designations
Alternative designations	1984 I;1990 XI
Orbital characteristics [1] [2]
Epoch	October 1, 2009
Aphelion	4.793 AU (Q)
Perihelion	2.240 AU (q)
Semi-major axis	3.517 AU (a)
Eccentricity	0.3630
Orbital period	6.60 yr
Inclination	6.182°
Last perihelion	21 May 2023
Next perihelion	17 December 2029 [3]
Physical characteristics
Mean radius	2.6 km (1.6 mi) [4]
Synodic rotation period	20.7 hours [5]
Geometric albedo	0.043±0.007
Spectral type	(V–R) = 0.62±0.05 [6]

94P/Russell 4 is a periodic comet in the Solar System.

Observational history

It was discovered by Kenneth S. Russell on photographic plates taken by M. Hawkins on March 7, 1984. ^[7] In the discovery images, Russell estimated that the comet had an apparent magnitude of 13 and a noticeable tail of 5 arcminutes. ^[7] In the year of discovery, the comet had come to perihelion in January 1984. ^[8]

Orbit

With an aphelion of 4.7 AU (700 million km), ^[1] comet 94P currently has an orbit contained completely inside of the orbit of Jupiter. It fits the definition of an Encke-type comet with (T_Jupiter > 3; a < a_Jupiter). ^[1]

Physical characteristics

In July 1995, 94P was estimated to have a radius of about 2.6 km (1.6 mi) with an absolute magnitude (H) of 15.1. ^[4] It may have a very elongated nucleus with an axial ratio of a/b ≥ 3. ^[4] It is determined that it has a rotation period of 20.7 hours. ^[5]

References

1. "94P/Russell 4 – JPL Small-Body Database Lookup". ssd.jpl.nasa.gov. Jet Propulsion Laboratory . Retrieved 19 February 2010.
2. "94P/Russell Orbit". Minor Planet Center . Retrieved 17 June 2014.
3. "Horizons Batch for 94P/Russell 4 (90000915) on 2029-Dec-17" (Perihelion occurs when rdot flips from negative to positive). JPL Horizons . Retrieved 29 April 2023. (JPL#74/Soln.date: 2023-Jul-05)
4. C. Snodgrass; S. C. Lowry; A. Fitzsimmons (2007). "Optical observations of 23 distant Jupiter Family Comets, including 36P/Whipple at multiple phase angles". Monthly Notices of the Royal Astronomical Society. 385 (2): 737–756. arXiv: 0712.4204 . Bibcode:2008MNRAS.385..737S. doi: 10.1111/j.1365-2966.2008.12900.x . S2CID   55536237.
5. B. E. A. Mueller; N. H. Samarasinha (2018). "Further Investigation of Changes in Cometary Rotation". The Astronomical Journal. 156 (3): 107–114. arXiv: 1806.11158 . Bibcode:2018AJ....156..107M. doi: 10.3847/1538-3881/aad0a1 .
6. M. M. Knight; R. Kokotanekova; N. H. Samarasinha (2023). "Physical and Surface Properties of Comet Nuclei from Remote Observations". arXiv: 2304.09309 [astro-ph.EP].
7. Kronk, Gary W. "94P/Russell 4" . Retrieved 19 February 2010. (Cometography Home Page)
8. Seiichi Yoshida (25 October 2008). "94P/Russell 4". Seiichi Yoshida's Comet Catalog. Retrieved 19 February 2010.

External links

• 94P/Russell at the JPL Small-Body Database
  • Close approach  · Discovery  · Ephemeris  · Orbit viewer  · Orbit parameters  · Physical parameters
• Elements and Ephemeris for 94P/Russell – Minor Planet Center
• 94P/Russell at the Minor Planet Center's Database
• 94P at Kazuo Kinoshita's Comets
• Images of 94P/Russell 4 from the 2010 passage

Numbered comets
Previous 93P/Lovas	94P/Russell	Next 95P/Chiron