189 Phthia

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189 Phthia
000189-asteroid shape model (189) Phthia.png
3D convex shape model of 189 Phthia
Discovery [1]
Discovered by C. H. F. Peters
Discovery site Clinton, New York
Discovery date9 September 1878
Designations
(189) Phthia
Pronunciation /ˈθ.ə/ [2]
A878 RA
main-belt
Orbital characteristics [3] [4]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc 136.18 yr (49739 d)
Aphelion 2.5415  AU (380.20  Gm)
Perihelion 2.3597 AU (353.01 Gm)
2.4506 AU (366.60 Gm)
Eccentricity 0.037105
3.84 yr (1401.2 d)
336.98°
0° 15m 24.912s / day
Inclination 5.1774°
203.42°
168.03°
Physical characteristics
Dimensions 37.66±2.0  km [3]
40.91 ± 1.36 km [5]
Mass (3.84 ± 0.81) × 1016 kg [5]
Mean density
1.07 ± 0.25 g/cm3 [5]
22.346  h (0.9311  d) [3] [6]
0.2310±0.027 [3]
0.1566 ± 0.0349 [7]
S [7] (Tholen)
9.33, [3] 9.60 [7]

    189 Phthia is a bright-coloured, rocky main belt asteroid that was discovered by German-American astronomer Christian Heinrich Friedrich Peters on September 9, 1878, [1] in Clinton, New York, and named after Phthia, a region of ancient Greece.

    Photometric observations of this asteroid at the Organ Mesa Observatory in Las Cruces, New Mexico, during 2008 gave a light curve with a period of 22.346 ± 0.001 hours and a brightness variation of 0.26 ± 0.02 in magnitude. [6]

    References

    1. 1 2 "Numbered Minor Planets 1–5000", Discovery Circumstances, IAU Minor Planet center, retrieved 7 April 2013.
    2. Noah Webster (1884) A Practical Dictionary of the English Language
    3. 1 2 3 4 5 Yeomans, Donald K., "189 Phthia", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory , retrieved 12 May 2016.
    4. "The Asteroid Orbital Elements Database". astorb. Lowell Observatory.
    5. 1 2 3 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.
    6. 1 2 Pilcher, Frederick (January 2009), "Period Determinations for 33 Polyhymnia, 38 Leda, 50 Virginia, 189 Phthia, and 290 Bruna", The Minor Planet Bulletin, vol. 36, no. 1, pp. 25–27, Bibcode:2009MPBu...36...25P.
    7. 1 2 3 Pravec, P.; et al. (May 2012), "Absolute Magnitudes of Asteroids and a Revision of Asteroid Albedo Estimates from WISE Thermal Observations", Asteroids, Comets, Meteors 2012, Proceedings of the conference held May 16–20, 2012 in Niigata, Japan, no. 1667, Bibcode:2012LPICo1667.6089P. See Table 4.