959 Arne

959 Arne

Discovery [1]
Discovered by	K. Reinmuth
Discovery site	Heidelberg Obs.
Discovery date	30 September 1921
Designations
MPC designation	(959) Arne
Named after	Arne Asplind (son of Bror Asplind)[2]
Alternative designations	A921 SE · 1927 YD 1952 DD2 · 1960 OF A916 YB · 1921 KF
Minor planet category	main-belt [1][3] · (outer) background [4][5]
Orbital characteristics [3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc	103.03 yr (37,630 d)
Aphelion	3.8813 AU
Perihelion	2.4752 AU
Semi-major axis	3.1782 AU
Eccentricity	0.2212
Orbital period (sidereal)	5.67 yr (2,070 d)
Mean anomaly	86.935°
Mean motion	0° 10^m 26.4^s / day
Inclination	4.4967°
Longitude of ascending node	58.521°
Argument of perihelion	333.57°
Physical characteristics
Mean diameter	45.176±0.350 km[6] 53.09±0.75 km[7] 57.42±1.5 km[8]
Synodic rotation period	123.7±0.1 h[9][10]
Geometric albedo	0.0446±0.002[8] 0.054±0.002[7] 0.067±0.004[6]
Spectral type	X (SDSS-MOC)[11]
Absolute magnitude (H)	10.8[1][3]

959 Arne (prov. designation: A921 SE or 1921 KF) is a background asteroid and slow rotator, approximately 52 kilometers (32 miles) in diameter, located in the outer region of the asteroid belt. It was discovered by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory on 30 September 1921.[1] The X-type asteroid has an exceptionally long rotation period of 123.7 hours. It was named after Arne Asplind, son of Swedish astronomer Bror Asplind (1890–1954).[2]

Orbit and classification

Arne is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.[4][5] It orbits the Sun in the outer asteroid belt at a distance of 2.5–3.9 AU once every 5 years and 8 months (2,070 days; semi-major axis of 3.18 AU). Its orbit has an eccentricity of 0.22 and an inclination of 4° with respect to the ecliptic.[3] The body's observation arc begins with its first observation as A916 YB (1916 YB) at Heidelberg Observatory on 27 December 1916, almost 5 years prior to its official discovery observation on 30 September 1921.[1]

Naming

This minor planet was named after Arne Asplind, son of Swedish astronomer Bror Ansgar Asplind (1890–1954). Asteroids 958 Asplinda, 960 Birgit and 961 Gunnie are named after him and his two daughters, respectively. The naming was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 92).[2]

Physical characteristics

In the SDSS-based taxonomy, Arne an X-type asteroid.[5][11]

Rotation period

In November 2007, a rotational lightcurve of Arne was obtained from photometric observations by Robert Stephens at GMARS (G79) and Santana observatories (646) in California. Analysis gave a bimodal lightcurve with an exceptionally long rotation period of 123.7±0.1 hours and a brightness amplitude of 0.24±0.05 magnitude (U=3−).[9][10] The results supersede an incorrect period of 8.60 hours from a noisy lightcurve taken by Larry E. Robinson at Sunflower Observatory (739) in Kansas in November 2001 (U=1).[12]

Diameter and albedo

According to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), the Japanese Akari satellite, and the Infrared Astronomical Satellite IRAS, Arne measures 45.176±0.350, 53.09±0.75 and 57.42±1.5 kilometers in diameter, and its surface has an albedo of 0.0446±0.002, 0.054±0.002 and 0.067±0.004, respectively.[6][7][8]

Other published measurements by the WISE team also includes mean-diameters of 46.687±0.665 km 51.539±0.547 km, 52.57±13.47 km and 61.45±20.10 km with corresponding albedos of 0.067±0.004, 0.0553±0.0301, 0.03±0.05 and 0.03±0.02.[5][9] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0258 and a diameter of 57.20 km based on an absolute magnitude of 10.8.[9] An asteroid occultation on 3 February 2015, gave a best-fit ellipse dimension of 53.0 × 53.0 kilometers.[5] These timed observations are taken when the asteroid passes in front of a distant star. However the quality of the measurements are poorly rated.[5]

References

1. "959 Arne (A921 SE)". Minor Planet Center. Retrieved 13 February 2020.
2. Schmadel, Lutz D. (2007). "(959) Arne". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 84. doi:10.1007/978-3-540-29925-7_960. ISBN 978-3-540-00238-3.
3. "JPL Small-Body Database Browser: 959 Arne (A921 SE)" (2020-01-06 last obs.). Jet Propulsion Laboratory. Retrieved 13 February 2020.
4. "Asteroid 959 Arne – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 13 February 2020.
5. "Asteroid 959 Arne". Small Bodies Data Ferret. Retrieved 13 February 2020.
6. Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121.
7. Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
8. Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 13 February 2020.
9. "LCDB Data for (959) Arne". Asteroid Lightcurve Database (LCDB). Retrieved 13 February 2020.
10. Stephens, Robert D. (June 2008). "Asteroids Observed from GMARS and Santana Observatories - Late 2007" (PDF). The Minor Planet Bulletin. 35 (2): 60–61. Bibcode:2008MPBu...35...60S. ISSN 1052-8091. Archived from the original (PDF) on 13 February 2020. Retrieved 13 February 2020.
11. Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 13 February 2020. (PDS data set)
12. Robinson, Larry E. (June 2002). "Photometry of Five Difficult Asteroids: 309 Fraternitas, 366 Vincentina 421 Zahringia, 578 Happelia, 959 Anne" (PDF). The Minor Planet Bulletin. 29 (2): 30–31. Bibcode:2002MPBu...29...30R. ISSN 1052-8091. Retrieved 13 February 2020.

External links

• Lightcurve Database Query (LCDB), at www.minorplanet.info
• Dictionary of Minor Planet Names, Google books
• Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
• 959 Arne at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• 959 Arne at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters