1479 Inkeri

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
1479 Inkeri
Discovery [1]
Discovered by Y. Väisälä
Discovery site Turku Obs.
Discovery date 16 February 1938
MPC designation (1479) Inkeri
Named after
(former Finnish province)
(discoverer's family members)
1938 DE · 1934 FR
1956 JD · A916 AC
A923 RG
main-belt · (middle)[3]
background [4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 93.63 yr (34,199 days)
Aphelion 3.1920 AU
Perihelion 2.1636 AU
2.6778 AU
Eccentricity 0.1920
4.38 yr (1,601 days)
0° 13m 29.64s / day
Inclination 7.3024°
Physical characteristics
Dimensions 15.206±0.117 km[5][6]
18.35 km (calculated)[3]
18.83±5.10 km[7]
22.70±0.56 km[8]
31.86±0.33 km[9]
5 h (dated)[10]
12.55 h (dated)[11]
660±5 h[12]
0.10 (assumed)[3]
Tholen = XFU [1][3]
B–V = 0.699[1]
11.40[6][8] · 11.80[3][9] · 11.9[1] · 12.00[7] · 12.45±1.49[13]

1479 Inkeri, provisional designation 1938 DE, is an asteroid from the central regions of the asteroid belt. It is an exceptionally slow rotator, suspected tumbler and measures approximately 19 kilometers in diameter. It was discovered on 16 February 1938, by Finnish astronomer Yrjö Väisälä at the Iso-Heikkilä Observatory in Turku, Finland.[14] "Inkeri" is the name of two of the discoverer's younger relatives as well as the local name of the former Finnish province of Ingria.[2]

Orbit and classification[edit]

Inkeri is a non-family asteroid from the main belt's background population.[4] It orbits the Sun in the central asteroid belt at a distance of 2.2–3.2 AU once every 4 years and 5 months (1,601 days). Its orbit has an eccentricity of 0.19 and an inclination of 7° with respect to the ecliptic.[1]

The asteroid was first identified as A916 AC at Simeiz Observatory in January 1916. The body's observation arc begins with its identification as 1923 RG at Heidelberg Observatory in September 1923, more than 14 years prior to its official discovery observation at Turku.[14]

Physical characteristics[edit]

In the Tholen classification, Inkeri's spectral type is ambiguous (XFU). It is closest to that of an X-type asteroid and somewhat similar to the F-types. In addition, the spectrum has also been flagged as "unusual" (U).[1]

Slow rotator and tumbler[edit]

In December 2011, a rotational lightcurve of Inkeri was obtained from photometric observations by Andrea Ferrero at the Bigmuskie Observatory (B88), Italy, in collaboration with Frederick Pilcher at the Organ Mesa Observatory (G50) in New Mexico, United States. Analysis of the bimodal lightcurve gave an exceptionally long rotation period of 660 hours with a brightness amplitude of 1.30 magnitude (U=2+).[12]

This makes it one of the slowest rotators known to exist. The observers also suspect that the body is a tumbling asteroid in a non-principal axis rotation.[12] These results supersede previous period solutions of 5 and 12.55 hours (U=1/1).[10][11]

Diameter and albedo[edit]

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Inkeri measures between 15.206 and 31.86 kilometers in diameter and its surface has an albedo between 0.033 and 0.2222.[5][6][7][8][9]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 and calculates a diameter of 18.35 kilometers based on an absolute magnitude of 11.8.[3]


This minor planet was named "Inkeri", a Finnish female name, held by Vaisala's granddaughter and niece. It is also the Finnish name of Ingria, a formerly-Finnish province near Saint Petersburg that is now part of Russia.[2] The official naming citation was published by the Minor Planet Center before November 1977 (M.P.C. 1350).[15]


  1. ^ a b c d e f g "JPL Small-Body Database Browser: 1479 Inkeri (1938 DE)" (2017-05-01 last obs.). Jet Propulsion Laboratory. Retrieved 20 October 2017. 
  2. ^ a b c Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1479) Inkeri. Springer Berlin Heidelberg. p. 118. ISBN 978-3-540-00238-3. Retrieved 20 October 2017. 
  3. ^ a b c d e f "LCDB Data for (1479) Inkeri". Asteroid Lightcurve Database (LCDB). Retrieved 20 October 2017. 
  4. ^ a b "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Retrieved 20 October 2017. 
  5. ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096Freely accessible. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 20 October 2017. 
  6. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407Freely accessible. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 20 October 2017. 
  7. ^ 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:1606.08923Freely accessible. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63. Retrieved 20 October 2017. 
  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. Retrieved 20 October 2017. 
  9. ^ 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:1209.5794Freely accessible. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. Retrieved 20 October 2017. 
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1479) Inkeri". Geneva Observatory. Retrieved 20 October 2017. 
  11. ^ a b Brinsfield, James W. (September 2008). "Asteroid Lightcurve Analysis at the Via Capote Observatory: First Quarter 2008". The Minor Planet Bulletin. 35 (3): 119–122. Bibcode:2008MPBu...35..119B. ISSN 1052-8091. Retrieved 20 October 2017. 
  12. ^ a b c Ferrero, Andrea; Pilcher, Frederick (July 2012). "The Very Long Period of 1479 Inkeri". The Minor Planet Bulletin. 39 (3): 192–193. Bibcode:2012MPBu...39..192F. ISSN 1052-8091. Retrieved 20 October 2017. 
  13. ^ 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:1506.00762Freely accessible. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 20 October 2017. 
  14. ^ a b "1479 Inkeri (1938 DE)". Minor Planet Center. Retrieved 20 October 2017. 
  15. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 20 October 2017. 

External links[edit]