{{Short description|Main-belt asteroid}} {{Use British English|date=June 2017}} {{Use dmy dates|date=May 2020}} {{Infobox planet | minorplanet = yes | name = 6223 Dahl | background = #D6D6D6 | image = NGC772 SN2003hl SN2003iq 6223 Dahl.jpg | image_scale = | caption = {{longitem|Track of ''Dahl'' next to NGC 772 with two supernovae |style=padding: 4px 0; line-height: 1.3em;}} | discovery_ref = <ref name="jpldata" /> | discovered = 3 September 1980 | discoverer = A. Mrkos | discovery_site = Kleť Obs. | mpc_name = (6223) Dahl | alt_names = {{mp|1980 RD|1}}{{·}}1949 XC<br />1972 YS{{·}}{{mp|1976 UV|3}}<br />{{mp|1982 BH|9}}{{·}}{{mp|1991 AK|3}} | named_after = Roald Dahl<br />{{small|(Welsh author)}}<ref name="springer" /> | mp_category = main-belt{{·}}{{small|(middle)}} | orbit_ref = <ref name="jpldata" /> | epoch = 4 September 2017 (JD 2458000.5) | uncertainty = 0 | observation_arc = 67.02 yr (24,479 days) | aphelion = 3.0674 AU | perihelion = 2.4039 AU | semimajor = 2.7356 AU | eccentricity = 0.1213 | period = 4.52 yr (1,653 days) | mean_anomaly = 38.698° | mean_motion = {{Deg2DMS|0.2178|sup=ms}} / day | inclination = 3.8564° | asc_node = 294.31° | arg_peri = 76.334° | dimensions = 16.81 km {{small|(calculated)}}<ref name="lcdb" /><br />{{nowrap|{{val|19.634|0.326}} km<ref name="WISE" /><ref name="Masiero-2011" />}} | rotation = {{val|3.33|0.01}} h<ref name="Waller-2013" /> | albedo = {{val|0.033|0.004}}<ref name="Masiero-2011" /><br />{{val|0.0335|0.0040}}<ref name="WISE" /><br />0.057 {{small|(assumed)}}<ref name="lcdb" /> | spectral_type = C<ref name="lcdb" /> | abs_magnitude = 12.6<ref name="jpldata" /><ref name="lcdb" /><ref name="WISE" /> }}
'''6223 Dahl''', provisional designation {{mp|1980 RD|1}}, is a carbonaceous asteroid from the central region of the asteroid belt, approximately 18 kilometres in diameter. It was discovered on 3 September 1980, by Czech astronomer Antonín Mrkos at Kleť Observatory near České Budějovice in the Czech Republic.<ref name="MPC-Dahl" /> The asteroid was named after author of children's books, Roald Dahl.<ref name="springer" />
== Orbit and classification ==
''Dahl'' orbits the Sun in the central main-belt at a distance of 2.4–3.1 AU once every 4 years and 6 months (1,653 days). Its orbit has an eccentricity of 0.12 and an inclination of 4° with respect to the ecliptic.<ref name="jpldata" /> The first precovery was taken at the US Goethe Link Observatory in 1949, extending the asteroid's observation arc by 31 years prior to its discovery.<ref name="MPC-Dahl" />
== Physical characteristics ==
''Dahl'' has been characterised as a dark, carbonaceous C-type asteroid.<ref name="lcdb" />
=== Lightcurves ===
In November 2011, a rotational lightcurve of ''Dahl'' was obtained by Brett Waller at the Cedar Green Observatory in Virginia in the United States. It gave a rotation period of {{val|3.33|0.01}} hours with a brightness variation of 0.43 in magnitude ({{small|U=2}}).<ref name="Waller-2013" />
=== Diameter and albedo ===
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, ''Dahl'' measures 19.6 kilometres in diameter and its surface has a low albedo of 0.034,<ref name="WISE" /> while the ''Collaborative Asteroid Lightcurve Link'' assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 16.8 kilometres, as the higher the albedo (reflectivity), the lower a body's diameter for certain absolute magnitude.<ref name="lcdb" />
== Naming ==
This minor planet was named in memory of the Welsh author Roald Dahl (1916–1990), known for his classic children's books ''Willy Wonka and the Chocolate Factory'' and ''James and the Giant Peach''.<ref name="springer" /> The approved naming citation was published by the Minor Planet Center on 28 August 1996 ({{small|M.P.C. 27735}}).<ref name="MPC-Circulars-Archive" />
== References == <references>
<ref name="jpldata">{{cite web |type = 2016-12-21 last obs. |title = JPL Small-Body Database Browser: 6223 Dahl (1980 RD1) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2006223 |publisher = Jet Propulsion Laboratory |access-date = 21 June 2017}}</ref>
<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names – (6223) Dahl |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |page = 519 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_5731 |chapter = (6223) Dahl }}</ref>
<ref name="MPC-Dahl">{{cite web |title = 6223 Dahl (1980 RD1) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=6223 |access-date = 10 July 2016}}</ref>
<ref name="MPC-Circulars-Archive">{{cite web |title = MPC/MPO/MPS Archive |work = Minor Planet Center |url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html |access-date = 10 July 2016}}</ref>
<ref name="lcdb">{{cite LCDB|number = 6223 |access-date = 10 July 2016}}</ref>
<ref name="WISE">{{cite journal |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 |s2cid = 35447010 |access-date= 10 July 2016}}</ref>
<ref name="Waller-2013">{{cite journal |first = E. Brett |last = Waller |date = April 2013 |title = Lightcurve Photometry and Rotational Periods of 2890 Vilyujsk and 6223 Dahl |url = http://articles.adsabs.harvard.edu/full/2013MPBu...40..109W |journal = The Minor Planet Bulletin |volume = 40 |issue = 2 |pages = 109–110 |bibcode = 2013MPBu...40..109W |access-date= 10 July 2016}}</ref>
<ref name="Masiero-2011">{{cite journal |display-authors = 6 |first1 = Joseph R. |last1 = Masiero |first2 = A. K. |last2 = Mainzer |first3 = T. |last3 = Grav |first4 = J. M. |last4 = Bauer |first5 = R. M. |last5 = Cutri |first6 = J. |last6 = Dailey |first7 = P. R. M. |last7 = Eisenhardt |first8 = R. S. |last8 = McMillan |first9 = T. B. |last9 = Spahr |first10 = M. F. |last10 = Skrutskie |first11 = D. |last11 = Tholen |first12 = R. G. |last12 = Walker |first13 = E. L. |last13 = Wright |first14 = E. |last14 = DeBaun |first15 = D. |last15 = Elsbury |first16 = T. IV |last16 = Gautier |first17 = S. |last17 = Gomillion |first18 = A. |last18 = Wilkins |date = November 2011 |title = Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...68M |journal = The Astrophysical Journal |volume = 741 |issue = 2 |page = 20 |bibcode = 2011ApJ...741...68M |doi = 10.1088/0004-637X/741/2/68 |arxiv = 1109.4096 |s2cid = 118745497 |access-date= 5 December 2016}}</ref>
</references> <!-- end of reflist -->
== External links == * [http://www.minorplanet.info/PHP/lcdbsummaryquery.php Asteroid Lightcurve Database (LCDB)], query form ([http://www.minorplanet.info/lightcurvedatabase.html info] {{Webarchive|url=https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html |date=16 December 2017 }}) * [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] – Observatoire de Genève, Raoul Behrend * [https://www.minorplanetcenter.net/iau/lists/NumberedMPs005001.html Discovery Circumstances: Numbered Minor Planets (5001)-(10000)] – Minor Planet Center * {{AstDys|6223}} * {{JPL small body}}
{{Minor planets navigator |(6222) 1980 PB3 |number=6223 |6224 El Goresy}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Dahl}} 006223 Category:Discoveries by Antonín Mrkos Category:Named minor planets 6223 Dahl 19800903