2204 Lyyli
{{Short description|Dark asteroid}}
{{Use dmy dates|date=October 2019}}
{{Infobox planet
| minorplanet = yes
| name = 2204 Lyyli
| background = #FA8072
| image = 002204-asteroid shape model (2204) Lyyli.png
| image_scale =
| caption = Shape model of Lyyli from its lightcurve
| discovered = 3 March 1943
| discoverer = Y. Väisälä
| discovery_site = Turku Obs.
| mpc_name = (2204) Lyyli
| alt_names = 1943 EQ{{·}}1968 DN
| named_after = Lyyli Heinänen {{small|(Esperantist)}}
| mp_category = Mars-crosser
| epoch = 4 September 2017 (JD 2458000.5)
| uncertainty = 0
| observation_arc = 73.75 yr (26,937 days)
| aphelion = 3.6435 AU
| perihelion = 1.5354 AU
| semimajor = 2.5894 AU
| eccentricity = 0.4071
| period = 4.17 yr (1,522 days)
| mean_anomaly = 350.25°
| inclination = 20.561°
| asc_node = 160.45°
| arg_peri = 283.25°
| moid = 0.6872 AU
| mars_moid = 0.2547 AU
| mean_diameter = {{val|25.16|2.4|ul=km}} {{small|(IRAS:11)}}
25.27 km {{small|(derived)}}
{{val|27.12|1.31}} km
| rotation = {{val|9.51|0.01|ul=h}}
{{val|10|u=h}}
{{val|11.063|0.001}} h
{{val|11.09|0.01}} h
| albedo = {{val|0.020|0.002}}
{{val|0.0232|0.005}} {{small|(IRAS:11)}}
{{val|0.050|0.006}}
0.0537 {{small|(derived)}}
| spectral_type = SMASS = X {{·}}P {{·}}X
| abs_magnitude = {{val|11.61|0.44}}{{·}}11.78{{·}}12.1{{·}}12.70
}}
2204 Lyyli (prov. designation: {{mp|1943 EQ}}) is a dark asteroid and very eccentric Mars-crosser from the middle region of the asteroid belt, approximately {{convert|25|km|mi|abbr=off|sp=us}} in diameter. It was discovered on 3 March 1943 by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.
Orbit and classification
Lyyli orbits the Sun in the central main-belt at a distance of 1.5–3.6 AU once every 4 years and 2 months (1,522 days). Its orbit has an eccentricity of 0.41 and an inclination of 21° with respect to the ecliptic.
Naming
This minor planet 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. The official naming citation was published by the Minor Planet Center on 26 May 1983 ({{small|M.P.C. 7944}}).
Physical characteristics
Lyyli is an X-type asteroid in the SMASS classification. It has also been characterized as a P-type asteroid by NASA's NEOWISE mission.
It has a rotation period of 11 hours and a very low albedo between 0.02 and 0.05, according to the surveys carried out by IRAS, Akari, and WISE/NEOWISE. Other large Mars crossing minor planets include 132 Aethra and 323 Brucia, with diameters of 43 and 36 kilometers, respectively.
References
{{reflist|30em|refs=
|type = 2016-12-01 last obs.
|title = JPL Small-Body Database Browser: 2204 Lyyli (1943 EQ)
|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002204
|publisher = Jet Propulsion Laboratory
|access-date = 12 June 2017}}
|title = Dictionary of Minor Planet Names
|url = https://archive.org/details/dictionaryminorp00schm
|url-access = limited
|last = Schmadel | first = Lutz D.
|publisher = Springer Berlin Heidelberg
|chapter = (2204) Lyyli
|page = [https://archive.org/details/dictionaryminorp00schm/page/n192 179]
|date = 2007
|isbn = 978-3-540-00238-3
|doi = 10.1007/978-3-540-29925-7_2205}}
|title = 2204 Lyyli (1943 EQ)
|website = Minor Planet Center
|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=2204
|access-date = 7 December 2016}}
|title = MPC/MPO/MPS Archive
|website = Minor Planet Center
|url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html
|access-date = 7 December 2016}}
|title = LCDB Data for (2204) Lyyli
|publisher = Asteroid Lightcurve Database (LCDB)
|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=2204%7CLyyli
|access-date = 7 December 2016}}
|first1 = E. F. |last1 = Tedesco
|first2 = P. V. |last2 = Noah
|first3 = M. |last3 = Noah
|first4 = S. D. |last4 = Price
|date = October 2004
|title = IRAS Minor Planet Survey V6.0
|url = https://sbnarchive.psi.edu/pds3/iras/IRAS_A_FPA_3_RDR_IMPS_V6_0/data/diamalb.tab
|journal = NASA Planetary Data System
|pages = IRAS-A-FPA-3-RDR-IMPS-V6.0
|bibcode = 2004PDSS...12.....T
|access-date= 22 October 2019}}
|display-authors = 6
|first1 = Fumihiko |last1 = Usui
|first2 = Daisuke |last2 = Kuroda
|first3 = Thomas G. |last3 = Müller
|first4 = Sunao |last4 = Hasegawa
|first5 = Masateru |last5 = Ishiguro
|first6 = Takafumi |last6 = Ootsubo
|first7 = Daisuke |last7 = Ishihara
|first8 = Hirokazu |last8 = Kataza
|first9 = Satoshi |last9 = Takita
|first10 = Shinki |last10 = Oyabu
|first11 = Munetaka |last11 = Ueno
|first12 = Hideo |last12 = Matsuhara
|first13 = Takashi |last13 = Onaka
|date = October 2011
|title = Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey
|journal = Publications of the Astronomical Society of Japan
|volume = 63
|issue = 5
|pages = 1117–1138
|bibcode = 2011PASJ...63.1117U
|doi = 10.1093/pasj/63.5.1117
|doi-access= free
}} ([http://vizier.cfa.harvard.edu/viz-bin/VizieR-5?-source=J/PASJ/63/1117/acua_v1&Num=2204 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])
|display-authors = 6
|first1 = A. |last1 = Mainzer
|first2 = T. |last2 = Grav
|first3 = J. |last3 = Masiero
|first4 = E. |last4 = Hand
|first5 = J. |last5 = Bauer
|first6 = D. |last6 = Tholen
|first7 = R. S. |last7 = McMillan
|first8 = T. |last8 = Spahr
|first9 = R. M. |last9 = Cutri
|first10 = E. |last10 = Wright
|first11 = J. |last11 = Watkins
|first12 = W. |last12 = Mo
|first13 = C. |last13 = Maleszewski
|date = November 2011
|title = NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...90M
|journal = The Astrophysical Journal
|volume = 741
|issue = 2
|page = 25
|bibcode = 2011ApJ...741...90M
|doi = 10.1088/0004-637X/741/2/90
|arxiv = 1109.6407
|access-date= 2 May 2016}}
|first1 = R. A. |last1 = Mohamed
|first2 = Yu. N. |last2 = Krugly
|first3 = F. P. |last3 = Velichko
|date = April 1994
|title = Photometry of two Mars-crossing asteroids 2078 Nanking and 2204 Lyyli
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=1994P&SS...42..341M
|journal = Planetary and Space Science
|volume = 42
|issue = 4
|pages = 341–343
|bibcode = 1994P&SS...42..341M
|doi = 10.1016/0032-0633(94)90107-4
|access-date= 7 December 2016}}
|first1 = R. |last1 = Gil-Hutton
|last2 = Cañ
|first3 = M. |last3 = ada
|date = April 2003
|title = Photometry of Fourteen Main Belt Asteroids
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2003RMxAA..39...69G
|journal = Revista Mexicana de Astronomía y Astrofísica |volume=39
|pages = 69–76
|bibcode = 2003RMxAA..39...69G
|access-date= 7 December 2016}}
|last1 = Warner |first1 = Brian D.
|date = October 2010
|title = Asteroid Lightcurve Analysis at the Palmer Divide Observatory: 2010 March - June
|journal = Minor Planet Bulletin
|url = http://www.minorplanet.info/MPB/issues/MPB_37-4.pdf
|volume = 37
|issue = 4
|pages = 161–165
|bibcode = 2010MPBu...37..161W
|issn = 1052-8091
|access-date= 18 March 2020}}
|last1 = Warner
|first1 = Brian D.
|date = January 2016
|title = Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2015 June-September
|journal = Minor Planet Bulletin
|url = http://www.minorplanet.info/MPB/issues/MPB_43-1.pdf
|volume = 43
|issue = 1
|pages = 57–65
|bibcode = 2016MPBu...43...57W
|issn = 1052-8091
|access-date = 18 March 2020
|archive-date = 3 October 2020
|archive-url = https://web.archive.org/web/20201003113200/http://www.minorplanet.info/MPB/issues/MPB_43-1.pdf
|url-status = dead
}}
|display-authors = 6
|first1 = Peter |last1 = Veres
|first2 = Robert |last2 = Jedicke
|first3 = Alan |last3 = Fitzsimmons
|first4 = Larry |last4 = Denneau
|first5 = Mikael |last5 = Granvik
|first6 = Bryce |last6 = Bolin
|first7 = Serge |last7 = Chastel
|first8 = Richard J. |last8 = Wainscoat
|first9 = William S. |last9 = Burgett
|first10 = Kenneth C. |last10 = Chambers
|first11 = Heather |last11 = Flewelling
|first12 = Nick |last12 = Kaiser
|first13 = Eugen A. |last13 = Magnier
|first14 = Jeff S. |last14 = Morgan
|first15 = Paul A. |last15 = Price
|first16 = John L. |last16 = Tonry
|first17 = Christopher |last17 = Waters
|date = November 2015
|title = Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V
|journal = Icarus
|volume = 261
|pages = 34–47
|bibcode = 2015Icar..261...34V
|doi = 10.1016/j.icarus.2015.08.007
|arxiv = 1506.00762
|access-date= 7 December 2016}}
}}
External links
- [http://www.minorplanetobserver.com/pdolc/A2204_2010.HTM Lightcurve plot of 2204 Lyyli], Palmer Divide Observatory, B. D. Warner (2010)
- [http://www.minorplanet.info/PHP/OneAsteroidInfo.php Lightcurve Database Query] (LCDB), at www.minorplanet.info
- [https://books.google.com/books?id=aeAg1X7afOoC&pg Dictionary of Minor Planet Names], Google books
- [http://obswww.unige.ch/~behrend/page_cou.html Asteroids and comets rotation curves, CdR] – Geneva Observatory, Raoul Behrend
- [https://www.minorplanetcenter.net/iau/lists/NumberedMPs000001.html Discovery Circumstances: Numbered Minor Planets (1)-(5000)] – Minor Planet Center
- {{AstDys|2204}}
- {{JPL small body}}
{{Minor planets navigator |2203 van Rhijn |number=2204 |2205 Glinka}}
{{Small Solar System bodies}}
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{{DEFAULTSORT:Lyyli}}