5638 Deikoon /diːˈɪkoʊɒn/ is a mid-sized Jupiter trojan from the Trojan camp, approximately 44 kilometers (27 miles) in diameter. It was discovered on 10 October 1988 by American astronomer couple Carolyn and Eugene Shoemaker at the Palomar Observatory in California.[1] The dark and possibly spherical D-type asteroid has a rotation period of 19.4 hours.[7] It was named after the Trojan hero Deicoon from Greek mythology.[1]
| Discovery [1] | |
|---|---|
| Discovered by | C. S. Shoemaker E. M. Shoemaker |
| Discovery site | Palomar Obs. |
| Discovery date | 10 October 1988 |
| Designations | |
| (5638) Deikoon | |
| Pronunciation | /diːˈɪkoʊɒn/[2] |
Named after | Δηικόων Dēikoōn[1] (Greek mythology) |
| 1988 TA3 · 1988 RJ1 1989 TO2 | |
| Jupiter trojan [1][3] Trojan [4] · background [5] | |
| Orbital characteristics [3] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 29.43 yr (10,751 d) |
| Aphelion | 5.8119 AU |
| Perihelion | 4.6861 AU |
| 5.2490 AU | |
| Eccentricity | 0.1072 |
| 12.03 yr (4,392 d) | |
| 260.33° | |
| 0° 4m 55.2s / day | |
| Inclination | 10.908° |
| 156.02° | |
| 91.817° | |
| Jupiter MOID | 0.1902 AU |
| TJupiter | 2.9520 |
| Physical characteristics | |
| 41.45±0.48 km[6] 44.22 km (calculated)[7] 63.33±3.32 km[8] | |
| 19.40±0.01 h[9] | |
| 0.044±0.005[8] 0.057 (assumed)[7] 0.071±0.010[6] | |
| D (Pan-STARRS)[7][10] D (SDSS-MOC)[11][12] B–V = 0.730±0.060[13] V–R = 0.430±0.040[13] V–I = 0.910±0.041[7] | |
| 10.00[8] 10.4[6] 10.5[1][3][7] | |
Orbit and classification
editDeikoon is a dark Jupiter trojan in a 1:1 orbital resonance with Jupiter. It is located in the trailering Trojan camp at the Gas Giant's L5 Lagrangian point, 60° behind its orbit .[4] It is also a non-family asteroid of the Jovian background population.[5]
It orbits the Sun at a distance of 4.7–5.8 AU once every 12.03 years (4,392 days; semi-major axis of 5.25 AU). Its orbit has an eccentricity of 0.11 and an inclination of 11° with respect to the ecliptic.[3] The body's observation arc begins with a precovery taken at Palomar in August 1988, just two months prior to its official discovery observation.[1]
Physical characteristics
editDeikoon is a dark D-type asteroid, the most common spectral type among the Jupiter trojans, according to the SDSS-based taxonomy and the survey conducted by Pan-STARRS.[7][10][11][12] It has a typical V–I color index of 0.91.[7]
Rotation period
editIn February 1994, a rotational lightcurve of Deikoon was obtained from six nights of photometric observations by Stefano Mottola and Anders Erikson using the ESO 1-metre telescope at the La Silla Observatory in Chile. The irregular lightcurve showed a rotation period of 19.40±0.01 hours and a low brightness variation of 0.07 magnitude (U=2-).[7][14]
In March 2007, a refined period of 19.40±0.01 hours with an amplitude of 0.14 magnitude was obtained by Lawrence Molnar at Calvin College, remotely operating the 0.4-meter telescope at the Calvin-Rehoboth Robotic Observatory in New Mexico (U=2).[7][9] A low brightness amplitude is indicative of a spherical rather than elongated shape.
Diameter and albedo
editAccording to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer and the Japanese Akari satellite, Deikoon measures 41.45 and 63.33 kilometers in diameter and its surface has an albedo of 0.071 and 0.044, respectively.[6][8] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 44.22 kilometers based on an absolute magnitude of 10.5.[7]
Naming
editThis minor planet was named from Greek mythology after the Trojan hero Deicoon, son of Pergasos and a friend of Aeneas. During the Trojan War, Deicoon was killed by Agamemnon's spear penetrating his shield.[1] The official naming citation was published by the Minor Planet Center on 12 July 1995 (M.P.C. 25444).[15]
References
edit- ^ a b c d e f g h "5638 Deikoon (1988 TA3)". Minor Planet Center. Retrieved 22 June 2018.
- ^ Noah Webster (1884) A Practical Dictionary of the English Language
- ^ a b c d "JPL Small-Body Database Browser: 5638 Deikoon (1988 TA3)" (2018-01-24 last obs.). Jet Propulsion Laboratory. Retrieved 22 June 2018.
- ^ a b "List of Jupiter Trojans". Minor Planet Center. 1 June 2018. Retrieved 22 June 2018.
- ^ a b "Asteroid (5638) Deikoon – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 22 June 2018.
- ^ a b c d Grav, T.; Mainzer, A. K.; Bauer, J. M.; Masiero, J. R.; Nugent, C. R. (November 2012). "WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy". The Astrophysical Journal. 759 (1): 10. arXiv:1209.1549. Bibcode:2012ApJ...759...49G. doi:10.1088/0004-637X/759/1/49. S2CID 119101711. (online catalog)
- ^ a b c d e f g h i j k "LCDB Data for (5638) Deikoon". Asteroid Lightcurve Database (LCDB). Retrieved 22 June 2018.
- ^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
- ^ a b Molnar, Lawrence A.; Haegert, Melissa, J.; Hoogeboom, Kathleen M. (June 2008). "Lightcurve Analysis of an Unbiased Sample of Trojan Asteroids". The Minor Planet Bulletin. 35 (2): 82–84. Bibcode:2008MPBu...35...82M. ISSN 1052-8091.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ a b Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339.
- ^ a b Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 30 October 2019. (PDS data set)
- ^ a b "Asteroid 5638 Deikoon". Small Bodies Data Ferret. Retrieved 22 June 2018.
- ^ a b Chatelain, Joseph P.; Henry, Todd J.; French, Linda M.; Winters, Jennifer G.; Trilling, David E. (June 2016). "Photometric colors of the brightest members of the Jupiter L5 Trojan cloud". Icarus. 271: 158–169. Bibcode:2016Icar..271..158C. doi:10.1016/j.icarus.2016.01.026.
- ^ Mottola, Stefano; Di Martino, Mario; Erikson, Anders; Gonano-Beurer, Maria; Carbognani, Albino; Carsenty, Uri; et al. (May 2011). "Rotational Properties of Jupiter Trojans. I. Light Curves of 80 Objects". The Astronomical Journal. 141 (5): 32. Bibcode:2011AJ....141..170M. doi:10.1088/0004-6256/141/5/170.
- ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 22 June 2018.
External links
edit- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- Dictionary of Minor Planet Names, Google books
- Discovery Circumstances: Numbered Minor Planets (5001)-(10000) – Minor Planet Center
- 5638 Deikoon at AstDyS-2, Asteroids—Dynamic Site
- 5638 Deikoon at the JPL Small-Body Database
