(16) psyche

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Asteroid
(16) psycheAstronomical symbol of psyche
Image taken by the Very Large Telescope on November 30, 2018
Image taken by the Very Large Telescope on November 30, 2018
Properties of the orbit ( animation )
Orbit type Main belt asteroid
Major semi-axis 2.926  AU
eccentricity 0.1349
Perihelion - aphelion 2.531 AU - 3.320 AU
Inclination of the orbit plane 3.10 °
Length of the ascending node 150.3 °
Argument of the periapsis 227.5 °
Time of passage of the perihelion 17th April 2015
Sidereal period 5 a 2 d
Mean orbital velocity 17.34 km / s
Physical Properties
Medium diameter 226 km
Dimensions 2.72 ± 0.75 x 10 19Template: Infobox asteroid / maintenance / mass kg
Albedo 0.12
Medium density 4.5 ± 1.4 g / cm³
Rotation period 4 h 12 min
Absolute brightness 5.9 likes
Spectral class
(according to Tholen) 		M.
Spectral class
(according to SMASSII) 		X
history
Explorer Annibale De Gasparis
Date of discovery March 17, 1852
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items.

(16) Psyche is an asteroid of the main asteroid belt discovered by Annibale De Gasparis on April 17, 1852 . The heavenly body was named after Psyche , the wife of the Greek god Eros .

description

Animation of the orbit of Psyche

The psyche moves at a distance of 2.5 ( perihelion ) to 3.3 (aphelion) astronomical units around the sun in around 5 years . The orbit is inclined 3.1 ° to the ecliptic , the orbit eccentricity is 0.135.

With a diameter of 250 km, Psyche is one of the largest asteroids in the main belt. It has a relatively light surface with an albedo of 0.12. It rotates once around its own axis in 4 hours and 12 minutes.

Radar observations showed that psyche is made up of iron and nickel. In contrast to other M-class asteroids, no water or material containing water could be detected on the surface. This also indicates a metallic asteroid. More recent measurements with the IRTF have found indications of small amounts of bound water on the surface of Psyche. This is interpreted as a consequence of collisions that could have occurred between Psyche and asteroids of the carbonaceous chondrite type .

If the density is too low to have a predominantly metallic composition, (16) Psyche is a candidate for the origin of the mesosiderites .

NASA mission

Psyche was selected as a target for an unmanned mission of the same name in January 2017 as part of NASA's Discovery program . The planned probe is to start in 2022 and from 2026 to explore the asteroid from an increasingly narrow orbit for at least one and a half years.

See also

Individual evidence

  1. ↑ a b c Radar observations and shape model of asteroid 16 Psyche echo.jpl.nasa.gov, PDF accessed on November 1, 2017
  2. ^ SJ Ostro: Radar observations of asteroids and comets . In: Astronomical Society of the Pacific, Publications . tape 97 , 1985, doi : 10.1086 / 131619 , bibcode : 1985PASP ... 97..877O .
  3. ↑ C. Magri: Mainbelt Asteroids: Results of Arecibo and Goldstone Radar Observations of 37 Objects during 1980-1995 . In: Icarus . tape 140 , no. 2 , 1999, doi : 10.1006 / icar.1999.6130 , bibcode : 1999Icar..140..379M .
  4. ↑ E. Merényi: Prediction of Water in Asteroids from Spectral Data Short Ward of 3 microns . In: Icarus . tape 129 , no. 2 , 1997, p. 421 , doi : 10.1006 / icar.1997.5796 , bibcode : 1997Icar..129..421M .
  5. ↑ Tilmann Althaus: Does psyche have water? In: Spectrum of Science. November 2, 2016, accessed January 10, 2017 .
  6. ^ DR Davis, Paolo Farinella, M. Francesco: The Missing Psyche Family: Collisionally Eroded or Never Formed? . In: Icarus . 137, No. 1, 1999, p. 140. bibcode : 1999Icar..137..140D . doi : 10.1006 / icar.1998.6037 .
  7. ↑ NASA Selects Two Missions to Explore the Early Solar System. January 4, 2017, accessed January 10, 2017 .
  8. ^ Arizona State University, Psyche Mission website