Undina (from Latin Undīna), minor planet designation 92 Undina, is a large main belt asteroid. The asteroid was discovered by Christian Peters on 7 July 1867 from the Hamilton College Observatory.[6] It is named for the eponymous heroine of Undine, a popular novella by Friedrich de la Motte Fouqué.

92 Undina
Discovery
Discovered byC. H. F. Peters
Discovery siteLitchfield Obs.
Discovery date7 July 1867
Designations
(92) Undina
Pronunciation/ʌnˈdnə/[1]
Main belt
AdjectivesUndinian /ʌnˈdɪniən/[2]
Orbital characteristics[3]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc145.11 yr (53001 d)
Aphelion3.51946 AU (526.504 Gm)
Perihelion2.85654 AU (427.332 Gm)
3.18800 AU (476.918 Gm)
Eccentricity0.10397
5.69 yr (2079.1 d)
6.12456°
0° 10m 23.347s / day
Inclination9.92900°
101.588°
239.494°
Physical characteristics
Mean diameter
126.42±3.4 km[3]
124.44 ± 3.25 km[4]
Mass(4.43 ± 0.25) × 1018 kg[4]
Mean density
4.39 ± 0.42 g/cm3[4]
15.941 h (0.6642 d)
0.2509±0.014[3]
0.251[5]
M
6.61

This minor planet is orbiting at a distance of around 3 AU from the Sun, which is known for a concentration of Tholen M-type asteroids. Indeed, 92 Undina has an unusually high albedo of 0.25 and an M-type spectrum, or Xc-type on the Bus taxonomy.[7] However, it displays absorption features at a wavelength of 3 μm, which is usually indicative of hydrated silicates on the surface.[8] There is a faint band in the region of 9 μm that is typically attributed to a form of orthopyroxene having low levels of calcium and iron. The spectrum of 92 Undina closely resembles powdered material from the Esquel meteorite, although with a higher albedo.[7]

Observations performed at the Palmer Divide Observatory in Colorado Springs, Colorado during 2007 produced a light curve with a period of 15.941 ± 0.002 hours with a brightness range of 0.20 ± 0.02 in magnitude. This matches a 15.94-hour period reported in 1979.[9] Attempts in 2014 to model the spin axis and shape based on light curve information proved inconclusive, but did indicate that "the pole latitude is not far removed from the ecliptic plane and rotation is probably retrograde".[10]

References edit

  1. ^ Hunter, Roe & Hooker (1906) The New American Encyclopedic Dictionary
  2. ^ Readings: the poetics of Blanchot, Joyce, Kafka, Kleist, Lispector, and Tsvetayeva (1991) Cixous
  3. ^ a b c "92 Undina". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 13 May 2016.
  4. ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, vol. 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
  5. ^ "Asteroid Data Sets". Archived from the original on 17 December 2009. Retrieved 14 January 2007.
  6. ^ Watson, J. (November 1867), "Minor Planets 93 and 94 discovered", Monthly Notices of the Royal Astronomical Society, 28: 15, Bibcode:1867MNRAS..28...15W.
  7. ^ a b Fornasier, S.; et al. (July 2011), "Spectroscopic survey of X-type asteroids", Icarus, 214 (1): 131−146, arXiv:1105.3380, Bibcode:2011Icar..214..131F, doi:10.1016/j.icarus.2011.04.022.
  8. ^ Burbine, T. H.; Binzel, R. P. (1994), "Asteroid Spectroscopy and Mineralogy", in Milani, Andrea; Di Martino, Michel; Cellino, A. (eds.), Asteroids, comets, meteors 1993: proceedings of the 160th International Astronomical Union, held in Belgirate, Italy, June 14-18, 1993, International Astronomical Union. Symposium no. 160, Kluwer Academic Publishers, Dordrecht, p. 255, Bibcode:1994IAUS..160..255B.
  9. ^ Warner, Brian D. (September 2007), "Asteroid Lightcurve Analysis at the Palmer Divide Observatory", The Minor Planet Bulletin, Bibcode:2007MPBu...34...72W.
  10. ^ Warner, Brian D. (October 2014), "Rotation Period, Spin Axis, and Shape Model for Main-belt Asteroid 92 Undina", The Minor Planet Bulletin, 41 (4): 230−233, Bibcode:2014MPBu...41..230W.

External links edit