(35671) 1998 SN165

(35671) 1998 SN165
Discovered byA. Gleason
Discovery siteKitt Peak Obs.
Discovery date23 September 1998
(35671) 1998 SN165
1998 SN165
TNO[2][3] · cubewano[4]
p-DP[5] · distant[1]
Orbital characteristics[2]
Epoch 1 July 2021 (JD 2459396.5)
Uncertainty parameter 2[1][2]
Observation arc22.26 yr (8,129 d)
Aphelion39.662 AU
Perihelion36.453 AU
38.058 AU
234.79 yr (85,755 d)
0° 0m 15.12s / day
15 July 2065[a]
Physical characteristics
Mean diameter
8.84 h[9]

(35671) 1998 SN165, prov. designation: 1998 SN165, is a trans-Neptunian object from the Kuiper belt located in the outermost region of the Solar System. It was discovered on 23 September 1998, by American astronomer Arianna Gleason at the Kitt Peak National Observatory near Tucson, Arizona. The cold classical Kuiper belt object is a dwarf planet candidate, as it measures approximately 400 kilometers (250 miles) in diameter. It has a grey-blue color (BB) and a rotation period of 8.8 hours.[13] As of 2021, it has not been named.[1]

Orbit and classification[]

1998 SN165 orbits the Sun at a distance of 36.5–39.7 AU once every 234 years and 9 months (85,755 days; semi-major axis of 38.06 AU). Its orbit has an eccentricity of 0.04 and an inclination of 5° with respect to the ecliptic.[2] As of 2021 the object is at 37.2 AU,[14] approaching the Sun until 15 July 2065, when it will come to perihelion.[a] The body's observation arc begins at Kitt Peak in September 1998, just eight nights prior to its official discovery observation.[1]

As a cubewano, also known as classical Kuiper belt object,[4] 1998 SN165 is located in between the resonant plutino and twotino populations and has a low-eccentricity orbit. It belongs to the cold population, distinct from the "stirred" hot population with inclinations higher than 5°. In a previous publication, the object was originally classified as a plutino.[15]

Numbering and naming[]

This minor planet was numbered by the Minor Planet Center on 27 February 2002 and received the number 35671 in the minor planet catalog (M.P.C. 44869).[16] As of 2021, it has not been named.[1] Acoording to the established naming conventions, it will receive a mythological or mythic name (not necessarily from Classical mythology), in particular one associated with creation.[17]

Physical characteristics[]

1998 SN165 has a blue-grey color (BB),[10] with various color indices measured,[7][13] giving a difference between the blue and red filter magnitude (BR) of 1.123 and 1.13, respectively.[3][11][12]

Rotation period[]

In February 2001, a rotational lightcurve of 1998 SN165 was obtained from photometric observations by Pedro Lacerda and Jane Luu. Lightcurve analysis gave an ambiguous rotation period of 8.84 hours with a brightness amplitude of 0.16 magnitude (U=2). An alternative period of 8.70 hours is also possible.[9][13]

Diameter and albedo[]

According to observations by the space-based Herschel and Spitzer telescopes, 1998 SN165 measures between 393 and 460 kilometers and its surface has a low albedo between 0.043 and 0.060.[6][7][8] While Johnston's Archive adopts a diameter of 393 kilometers, astronomer Michael Brown gives a radiometric diameter of 473 kilometers and lists this object as a "probable" dwarf planet (400–500 km), which is the category with the second lowest certainty in his 5-class taxonomic system.[5] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 and calculates a diameter of 334 kilometers based on an absolute magnitude of 5.5.[13] A generic magnitude-to-diameter conversion with an albedo of 0.9 gives a diameter of 352 kilometers.[18]


  1. ^ a b JPL Horizons Observer Location: @sun (Perihelion occurs when deldot changes from negative to positive. Uncertainty in time of perihelion is 3-sigma, ±9 days.)


  1. ^ a b c d e f g "35671 (1998 SN165)". Minor Planet Center. Retrieved 5 January 2019.
  2. ^ a b c d e "JPL Small-Body Database Browser: 35671 (1998 SN165)" (2017-09-24 last obs.). Jet Propulsion Laboratory. Retrieved 5 January 2019.
  3. ^ a b c d e Johnston, Wm. Robert (18 August 2020). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 27 July 2021.
  4. ^ a b "Orbit Fit and Astrometric record for 35671". Southwest Research Institute. Retrieved 27 July 2021.The Deep Ecliptic Survey Object Classifications
  5. ^ a b c d Brown, Michael E. "How many dwarf planets are there in the outer solar system?". California Institute of Technology. Retrieved 5 January 2019.
  6. ^ a b c Vilenius, E.; Kiss, C.; Müller, T.; Mommert, M.; Santos-Sanz, P.; Pál, A.; et al. (April 2014). ""TNOs are Cool": A survey of the trans-Neptunian region. X. Analysis of classical Kuiper belt objects from Herschel and Spitzer observations". Astronomy and Astrophysics. 564: 18. arXiv:1403.6309. Bibcode:2014A&A...564A..35V. doi:10.1051/0004-6361/201322416. S2CID 118513049.
  7. ^ a b c "Asteroid (35671) 1998 SN165". Small Bodies Data Ferret. Retrieved 5 January 2019.
  8. ^ a b c Stansberry, John; Grundy, Will; Brown, Michael E.; Cruikshank, Dale; Spencer, John; Trilling, David; Margot, Jean-Luc (2008). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope". In M. Antonietta Barucci; Hermann Boehnhardt; Dale P. Cruikshank; Alessandro Morbidelli (eds.). The Solar System beyond Neptune. University of Arizona Press. arXiv:astro-ph/0702538. Bibcode:2008ssbn.book..161S.
  9. ^ a b Lacerda, Pedro; Luu, Jane (April 2006). "Analysis of the Rotational Properties of Kuiper Belt Objects". The Astronomical Journal. 131 (4): 2314–2326. arXiv:astro-ph/0601257. Bibcode:2006AJ....131.2314L. doi:10.1086/501047. S2CID 14950702.
  10. ^ a b c d e Belskaya, Irina N.; Barucci, Maria A.; Fulchignoni, Marcello; Dovgopol, Anatolij N. (April 2015). "Updated taxonomy of trans-neptunian objects and centaurs: Influence of albedo". Icarus. 250: 482–491. Bibcode:2015Icar..250..482B. doi:10.1016/j.icarus.2014.12.004.
  11. ^ a b Peixinho, N.; Delsanti, A.; Guilbert-Lepoutre, A.; Gafeira, R.; Lacerda, P. (October 2012). "The bimodal colors of Centaurs and small Kuiper belt objects". Astronomy and Astrophysics. 546: 12. arXiv:1206.3153. Bibcode:2012A&A...546A..86P. doi:10.1051/0004-6361/201219057. S2CID 55876118.
  12. ^ a b c d Hainaut, O. R.; Boehnhardt, H.; Protopapa, S. (October 2012). "Colours of minor bodies in the outer solar system. II. A statistical analysis revisited". Astronomy and Astrophysics. 546: 20. arXiv:1209.1896. Bibcode:2012A&A...546A.115H. doi:10.1051/0004-6361/201219566. S2CID 54776793.
  13. ^ a b c d "LCDB Data for (35671)". Asteroid Lightcurve Database (LCDB). Retrieved 5 January 2019.
  14. ^ "(35671) 1998 SN165 – Ephemerides". AstDyS-2, Asteroids – Dynamic Site. Retrieved 27 July 2021.
  15. ^ Gil-Hutton, R.; Licandro, Javier (August 2001). "VR Photometry of Sixteen Kuiper Belt Objects". Icarus. 152 (2): 246–250. Bibcode:2001Icar..152..246G. doi:10.1006/icar.2001.6627.
  16. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 5 January 2019.
  17. ^ "Naming of Astronomical Objects – Minor planets". IAU – International Astronomical Union. Retrieved 27 July 2021.
  18. ^ "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 5 January 2019.

External links[]