118 Peitho is a main-belt asteroid. It is probably an S-type asteroid, suggesting a siliceous mineralogy. It was discovered by R. Luther on March 15, 1872, and named after one of the two Peithos in Greek mythology. There have been two observed Peithoan occultations of a dim star: one was in 2000 and the other in 2003.[4][5]
![]() 3D convex shape model of 118 Peitho | |
Discovery | |
---|---|
Discovered by | Karl Theodor Robert Luther |
Discovery date | 15 March 1872 |
Designations | |
(118) Peitho | |
Pronunciation | /ˈpaɪ |
Named after | Πειθώ Peithō |
A872 EA | |
Main belt | |
Adjectives | Peithoian /paɪˈ |
Orbital characteristics[2] | |
Epoch 31 July 2016 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 144.05 yr (52615 d) |
Aphelion | 2.8353 |
Perihelion | 2.03988 |
2.43757 | |
Eccentricity | 0.16315 |
3.81 yr (1390.1 d) | |
Average orbital speed | 18.95 km/s |
51.1620° | |
0° 15m 32.328s / day | |
Inclination | 7.7427° |
47.701° | |
33.403° | |
Earth MOID | 1.05849 |
Jupiter MOID | 2.4367 |
TJupiter | 3.473 |
Physical characteristics | |
Dimensions | 41.73±1.5 km |
Mass | 7.6×1016 kg |
Equatorial surface gravity | 0.0117 m/s2 |
Equatorial escape velocity | 0.0220 km/s |
7.8055 h (0.32523 d)[2] 7.823 h[3] | |
0.2240±0.017 | |
Temperature | ~178 K |
S | |
9.14 | |
This body is orbiting the Sun with a period of 3.81 years and an eccentricity (ovalness) of 0.16. The orbital plane is inclined by 7.7° to the plane of the ecliptic. The cross-section diameter is ~42 km. In 2009, Photometric observations of this asteroid were made at the Palmer Divide Observatory in Colorado Springs, Colorado. The resulting asymmetrical light curve shows a synodic rotation period of 7.823 ± 0.002 hours with a brightness variation of 0.15 ± 0.02 in magnitude. This was reasonably consistent with independent studies performed in 1980 (7.78 hours) and 2009 (7.8033 hours).[3] The lightcurve inversion process has been used to construct a model of this object,[6] suggesting a blocky shape with flattened poles.
References
edit- ^ 'Pitho' in Noah Webster (1884) A Practical Dictionary of the English Language
- ^ a b Yeomans, Donald K., "118 Peitho", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 12 May 2016.
- ^ a b Warner, Brian D. (October 2009), "Asteroid Lightcurve Analysis at the Palmer Divide Observatory: 2009 March-June", The Minor Planet Bulletin, vol. 36, no. 4, pp. 172–176, arXiv:1203.4336, Bibcode:2009MPBu...36..172W, doi:10.1016/j.pss.2012.03.009.
- ^ von Boinik, I. F. B. "Planet (118) Peitho". Astronomische Nachrichten. 145: 31. Bibcode:1897AN....145...31V. doi:10.1002/asna.18981450107.
- ^ "NASA Planetary Data System". Archived from the original on 1 August 2009. Retrieved 21 December 2009.
- ^ Franco, Lorenzo; et al. (July 2020), "Spin-Shape Model for 118 Peitho", Bulletin of the Minor Planets Section of the Association of Lunar and Planetary Observers, 47 (3): 169–171, Bibcode:2020MPBu...47..169F
External links
edit- Lightcurve plot of 118 Peitho, Palmer Divide Observatory, B. D. Warner (2009)
- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 118 Peitho at AstDyS-2, Asteroids—Dynamic Site
- 118 Peitho at the JPL Small-Body Database