2204 Lyyli
| Discovery [1] | |
|---|---|
| Discovered by | Y. Väisälä |
| Discovery site | Turku Observatory |
| Discovery date | 3 March 1943 |
| Designations | |
| 2204 Lyyli | |
Named after | Lyyli Heinänen (Esperantist)[2] |
| 1943 EQ · 1968 DN | |
| Mars crosser [1][3] | |
| Orbital characteristics [1] | |
| Epoch 13 January 2016 (JD 2457400.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 72.46 yr (26465 days) |
| Aphelion | 3.6433 AU (545.03 Gm) |
| Perihelion | 1.5343 AU (229.53 Gm) |
| 2.5888 AU (387.28 Gm) | |
| Eccentricity | 0.40734 |
| 4.17 yr (1521.4 d) | |
| 208.29° | |
| 0° 14m 11.832s / day | |
| Inclination | 20.562° |
| 160.45° | |
| 283.29° | |
| Earth MOID | 0.685111 AU (102.4911 Gm) |
| Jupiter MOID | 2.11069 AU (315.755 Gm) |
| TJupiter | 3.216 |
| Physical characteristics | |
| Dimensions | 25.16 km[4] 27.12±1.31 km[5] 25.27 km (derived)[3] |
| 12.58 ± 1.2 km | |
| 11.063 h (0.4610 d)[6] 10 h[7] 9.51±0.01 h[8] 11.09±0.01 h[a] | |
| 0.0232 ± 0.005[4] 0.020±0.002[5] 0.050±0.006[9] 0.0537 (derived)[3] | |
| SMASS = X X [3] | |
| 12.1 | |
2204 Lyyli, provisional designation 1943 EQ, is a dark asteroid and very eccentric Mars-crosser from the inner regions of the asteroid belt, about 25 kilometers in diameter. It was discovered on 3 March 1943 by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.[10]
The X-type asteroid orbits the Sun at a distance of 1.5–3.6 AU once every 4 years and 2 months (1,521 days). Its orbit shows an outstanding eccentricity of 0.41, which is also notably tilted by 21 degrees to the plane of the ecliptic. It has a rotation period of 11 hours[6] and a very low albedo between 0.02 and 0.05, according to the surveys carried out by IRAS, Akari, and WISE/NEOWISE.[4][5][9]
Other large Mars crossing minor planets include 132 Aethra and 323 Brucia, with diameters of 43 and 36 kilometers, respectively.
The asteroid was named in honour of Lyyli Heinänen (1903–1988), née Hartonen, a Finnish female Esperantist, professor of mathematics, amateur astronomer and former assistant of the discoverer.[2]
References
- ^ Warner (2015) web: rotation period 11.09±0.01 hours with a brightness amplitude of 0.39 mag. Summary figures at Collaborative Asteroid Lightcurve Link (CALL) for (2204) Lyyli
- ^ a b c "JPL Small-Body Database Browser: 2204 Lyyli (1943 EQ)" (2015-08-17 last obs.). Jet Propulsion Laboratory. Retrieved 15 April 2016.
- ^ a b Schmadel, Lutz D. (2003). Dictionary of Minor Planet Names – (2204) Lyyli. Springer Berlin Heidelberg. p. 179. ISBN 978-3-540-29925-7. Retrieved 25 November 2015.
- ^ a b c d "LCDB Data for (2204) Lyyli". Asteroid Lightcurve Database (LCDB). Retrieved 25 November 2015.
- ^ a b c Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. Bibcode:2004PDSS...12.....T. Retrieved 25 November 2015.
- ^ a b c 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. Retrieved 25 November 2015.
- ^ a b Warner, Brian D. (October 2010). "Asteroid Lightcurve Analysis at the Palmer Divide Observatory: 2010 March - June". The Minor Planet Bulletin. 37 (4): 161–165. Bibcode:2010MPBu...37..161W. ISSN 1052-8091. Retrieved 25 November 2015.
- ^ Mohamed, R. A.; Krugly, Yu. N.; Velichko, F. P. (April 1994). "Photometry of two Mars-crossing asteroids 2078 Nanking and 2204 Lyyli". Planetary and Space Science: 341–343. Bibcode:1994P&SS...42..341M. doi:10.1016/0032-0633(94)90107-4. Retrieved 25 November 2015.
- ^ Gil-Hutton, R.; Cañada, M. (April 2003). "Photometry of Fourteen Main Belt Asteroids". Revista Mexicana de Astronomía y Astrofísica. 39: 69–76(http://www.astroscu.unam.mx/~rmaa/)(RMxAAHomepage). Bibcode:2003RMxAA..39...69G. Retrieved 25 November 2015.
- ^ a b Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 25 November 2015.
- ^ "2204 Lyyli (1943 EQ)". Minor Planet Center. Retrieved 25 November 2015.
External links
- Asteroid Lightcurve Database (LCDB), query form (info)
- 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
- 2204 Lyyli at the JPL Small-Body Database
