![]() A three-dimensional model of 201 Penelope based on its light curve. | |
Discovery | |
---|---|
Discovered by | Johann Palisa |
Discovery date | 7 August 1879 |
Designations | |
(201) Penelope | |
Pronunciation | /pɪˈnɛləpiː/[1] |
Named after | Penelópē |
A879 PA; 1869 GA | |
Main belt | |
Adjectives | Penelopean /pɪˈnɛloʊˈpiːən/[1] |
Orbital characteristics[2] | |
Epoch 21 January 2022 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 142.58 yr (52,077 d)[3] |
Aphelion | 3.160 AU (472.710 Gm)[3] |
Perihelion | 2.199 AU (329.009 Gm)[4][3] |
2.680 AU (400.859 Gm)[4][3] | |
Eccentricity | 0.17924[4][3] |
4.39 yr (1,602.14 d)[3] | |
Average orbital speed | 18.19 km/s |
169.01173°[4] | |
0° 13m 28.917s / day[4] | |
Inclination | 5.75625°[4][3] |
156.91554°[4] | |
180.90559°[4] | |
Jupiter MOID | 2.23013 AU (333.623 Gm)[3] |
TJupiter | 3.347[3] |
Physical characteristics | |
Dimensions | 68.39±3.5 km[2] 87.72 km[5] |
3.7474 h (0.15614 d)[3] | |
0.1604±0.018[2] 0.0881±0.0187[5] | |
201 Penelope is a large main belt asteroid that was discovered by Austrian astronomer Johann Palisa on August 7, 1879, in Pola. The asteroid is named after Penelope, the wife of Odysseus in Homer's The Odyssey. It is orbiting the Sun at a distance of 2.68 AU with an eccentricity (ovalness) of 0.18 and a period of 4.381 years. The orbital plane is tilted at an angle of 5.8° to the plane of the ecliptic.[2]
Based upon the spectra of this object, it is classified as a M-type asteroid, indicating it may be metallic in composition.[5] It may be the remnant of the core of a larger, differentiated asteroid. Near infrared absorption features indicate the presence of variable amounts of low-iron, low-calcium orthopyroxenes on the surface. Trace amounts of water is detected with a mass fraction of about 0.13–0.15 wt%.[6] It has an estimated size of around 88 km.[5] With a rotation period of 3.74 hours, it is the fastest rotating asteroid larger than 50 km in diameter.[2]
References
[edit]- ^ a b "Penelope". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
- ^ a b c d e f "JPL Small-Body Database Search Engine: diameter > 50 (km) and rot_per > 0 (h)". JPL Solar System Dynamics. Retrieved 12 May 2016.
- ^ a b c d e f g h i j k l m n "Small-Body Database Lookup". ssd.jpl.nasa.gov. Retrieved 12 April 2022.
- ^ a b c d e f g h i "IAU Minor Planet Center". minorplanetcenter.net. Retrieved 12 April 2022.
- ^ a b c d e f 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.
- ^ Hardersen, Paul S.; Gaffey, Michael J.; Abell, Paul A. (January 1983), "Near-IR spectral evidence for the presence of iron-poor orthopyroxenes on the surfaces of six M-type asteroids", Icarus, vol. 175, no. 1, pp. 141–158, Bibcode:2005Icar..175..141H, doi:10.1016/j.icarus.2004.10.017.
External links
[edit]- The Asteroid Orbital Elements Database
- Asteroid Lightcurve Parameters
- Asteroid Albedo Compilation
- 201 Penelope at AstDyS-2, Asteroids—Dynamic Site
- 201 Penelope at the JPL Small-Body Database
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction