1424 Sundmania (prov. designation: 1937 AJ) is a large asteroid and rather slow rotator from the background population of the outer regions of the asteroid belt. It was discovered on 9 January 1937, by astronomer Yrjö Väisälä at the Turku Observatory in southwest Finland.[15] The dark X-type asteroid has a notably long rotation period of 93.7 hours and measures approximately 70 kilometers (43 miles) in diameter. It was named after Finnish astronomer and mathematician Karl F. Sundman.[2]

1424 Sundmania
Shape model of Sundmania from its lightcurve
Discovery[1]
Discovered byY. Väisälä
Discovery siteTurku Obs.
Discovery date9 January 1937
Designations
(1424) Sundmania
Named after
Karl F. Sundman[2][3]
(Finnish mathematician)
1937 AJ · 1929 SS
1929 UB · 1931 AD
1938 FP · A918 WA
main-belt · (outer)[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc98.53 yr (35,989 days)
Aphelion3.3831 AU
Perihelion2.9966 AU
3.1899 AU
Eccentricity0.0606
5.70 yr (2,081 days)
196.29°
0° 10m 22.8s / day
Inclination9.1784°
42.988°
301.53°
Physical characteristics
64.691±0.254 km[5]
68.169±1.767 km[6]
70.56 km (derived)[4]
70.75±2.5 km[7]
73.40±0.86 km[8]
74.46±16.37 km[9]
80.20±28.15 km[10]
84.67±0.64 km[11]
93.73±0.03 h[12]
  • (51.0°, 76.0°) (λ11)[13]
  • (275.0°, 58.0°) (λ22)[13]
0.030±0.004[11]
0.03±0.01[9]
0.03±0.04[10]
0.0426 (derived)[4]
0.052±0.001[8]
0.0559±0.004[7]
0.0602±0.0136[6]
SMASS = X[1] · P[6] · C[4]
9.50[6][7][8] · 9.80[4][11] · 9.90[1][9] · 10.03±0.38[14] · 10.07[10]

Orbit and classification

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Sundmania is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the outer main-belt at a distance of 3.0–3.4 AU once every 5 years and 8 months (2,081 days). Its orbit has an eccentricity of 0.06 and an inclination of 9° with respect to the ecliptic.[1] The body's observation arc begins with its first identification as A918 WA at Heidelberg Observatory in November 1918, more than 18 years prior to its official discovery observation at Turku.[15]

Naming

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This minor planet was named after Finnish mathematician Karl F. Sundman (1873–1949), who intensively worked on the n-body problem. Sundman worked as an astronomer at several observatories all over Europe. He became director of the Helsinki University Observatory and was appointed professor of astronomy at the University of Helsinki in 1907. The asteroids 1558 Järnefelt and 1559 Kustaanheimo were also named after astronomers from the University of Helsinki.[2][3] The naming was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 129). The lunar crater Sundman was also named in his honor.[2]

Physical characteristics

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In the SMASS classification, Sundmania is an X-type asteroid.[1] It has also been characterized as a primitive P-type by the Wide-field Infrared Survey Explorer (WISE).[6] The Lightcurve Data Base assumes it to be a carbonaceous C-type asteroid.[4]

Rotation period

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Sundmania is a rather slow rotator as most minor planets have a rotation period of less than 20 hours.

In April 2012, a rotational lightcurve of Sundmania was obtained from photometric observations by American astronomer Robert Stephens at the Goat Mountain Astronomical Research Station (G79) in California. Lightcurve analysis gave a rotation period of 93.73 hours with a brightness amplitude of 0.42 magnitude (U=2+).[12] Observations by French amateur astronomers Laurent Bernasconi and René Roy gave a period of 36 and 47 hours, of which the latter seems to be half the period solution obtained by Stephens (U=1/1+).[16]

Spin axis

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In 2016, an international study modeled a lightcurve with a period of 94.537±0.005 hours and found two spin axes of (51.0°, 76.0°) and (275.0°, 58.0°) in ecliptic coordinates (λ, β).[13]

Diameter and albedo

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According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, Sundmania measures between 64.691 and 84.67 kilometers in diameter and its surface has an albedo between 0.030 and 0.0602.[5][6][7][8][9][10][11] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0426 and a diameter of 70.56 kilometers based on an absolute magnitude of 9.8.[4]

References

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  1. ^ a b c d e f "JPL Small-Body Database Browser: 1424 Sundmania (1937 AJ)" (2017-06-04 last obs.). Jet Propulsion Laboratory. Retrieved 20 September 2017.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1424) Sundmania". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 114. doi:10.1007/978-3-540-29925-7_1425. ISBN 978-3-540-00238-3.
  3. ^ a b Hannu Karttunen. "Observatory museum Biographies: 1900s — Sundman, Karl Frithiof (1873–1949)". University of Helsinky. Archived from the original on 16 June 2011.
  4. ^ a b c d e f g "LCDB Data for (1424) Sundmania". Asteroid Lightcurve Database (LCDB). Retrieved 20 September 2017.
  5. ^ a b 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. S2CID 119293330. Retrieved 20 September 2017.
  6. ^ a b c d e f Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. S2CID 35447010.
  7. ^ a b c d 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 22 October 2019.
  8. ^ a b c d 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)
  9. ^ a b c d Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T.; et al. (December 2015). "NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos". The Astrophysical Journal. 814 (2): 13. arXiv:1509.02522. Bibcode:2015ApJ...814..117N. doi:10.1088/0004-637X/814/2/117. S2CID 9341381. Retrieved 20 September 2017.
  10. ^ a b c d Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63.
  11. ^ a b c d Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. S2CID 46350317. Retrieved 20 September 2017.
  12. ^ a b Stephens, Robert D. (October 2012). "Asteroids Observed from Santana, CS3 and GMARS Observatories: 2012 April - June" (PDF). Minor Planet Bulletin. 39 (4): 226–228. Bibcode:2012MPBu...39..226S. ISSN 1052-8091. Retrieved 16 March 2020.
  13. ^ a b c Hanus, J.; Durech, J.; Oszkiewicz, D. A.; Behrend, R.; Carry, B.; Delbo, M.; et al. (February 2016). "New and updated convex shape models of asteroids based on optical data from a large collaboration network". Astronomy and Astrophysics. 586: 24. arXiv:1510.07422. Bibcode:2016A&A...586A.108H. doi:10.1051/0004-6361/201527441. S2CID 119112278.
  14. ^ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339. Retrieved 20 September 2017.
  15. ^ a b "1424 Sundmania (1937 AJ)". Minor Planet Center. Retrieved 20 September 2017.
  16. ^ Behrend, Raoul. "Asteroids and comets rotation curves – (1424) Sundmania". Geneva Observatory. Retrieved 20 September 2017.
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