{{Short description|Main-belt asteroid}} {{For|other uses of Malmquist|Malmquist (disambiguation)}} {{Use dmy dates|date=October 2019}} {{Infobox planet | minorplanet = yes | name = 1527 Malmquista | background = #D6D6D6 | image = 1527Malmquista (Lightcurve Inversion).png | image_scale = | caption = {{longitem|Lightcurve-based 3D-model of Malmquista|style=padding: 5px 0;}} | discovery_ref = <ref name="jpldata" /> | discovered = 18 October 1939 | discoverer = Y. Väisälä | discovery_site = Turku Obs. | mpc_name = (1527) Malmquista | alt_names = 1939 UG{{·}}1929 TG<br />1932 OB{{·}}1972 TK<br />A909 TC | pronounced = | named_after = Gunnar Malmquist<br />{{small|(astronomer)}}<ref name="springer" /> | mp_category = main-belt{{·}}Flora<ref name="lcdb" /> | orbit_ref = <ref name="jpldata" /> | epoch = 4 September 2017 (JD 2458000.5) | uncertainty = 0 | observation_arc = 87.47 yr (31,948 days) | aphelion = 2.6694 AU | perihelion = 1.7846 AU | semimajor = 2.2270 AU | eccentricity = 0.1987 | period = 3.32 yr (1,214 days) | mean_anomaly = 203.99° | mean_motion = {{Deg2DMS|0.2966|sup=ms}} / day | inclination = 5.1939° | asc_node = 16.133° | arg_peri = 304.49° | dimensions = {{val|9.55|0.49}} km<ref name="Masiero-2012" /><br />{{val|10.040|0.134}} km<ref name="Masiero-2014" /><br />{{val|10.338|0.071}} km<ref name="WISE" /><br />10.80 km {{small|(calculated)}}<ref name="lcdb" /> | rotation = {{val|14.044|0.0244}} h<ref name="Waszczak-2015" /><br />{{val|14.0591}} h<ref name="Hanus-2013c" /><br />{{val|14.077|0.004}} h<ref name="Brincat-2003" /> | albedo = {{val|0.2202|0.0169}}<ref name="WISE" /><br />0.24 {{small|(assumed)}}<ref name="lcdb" /><br />{{val|0.307|0.037}}<ref name="Masiero-2012" /> | spectral_type = S<ref name="lcdb" /> | abs_magnitude = 12.0<ref name="jpldata" /><ref name="lcdb" /><ref name="Masiero-2012" />{{·}}12.2<ref name="WISE" />{{·}}{{val|12.481|0.002}} {{small|(S)}}<ref name="Waszczak-2015" /> }}
'''1527 Malmquista''' (provisional designation '''{{mp|1939 UG}}''') is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 10 kilometers in diameter.
It was discovered on 18 October 1939, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.<ref name="MPC-Malmquista" /> It was named for the Swedish astronomer Gunnar Malmquist.<ref name="springer" />
== Orbit and classification ==
Malmquista is a member of the Flora family, one of the largest families of stony asteroids in the main belt. It orbits the Sun in the inner main-belt at a distance of 1.8–2.7 AU once every 3 years and 4 months (1,214 days). Its orbit has an eccentricity of 0.20 and an inclination of 5° with respect to the ecliptic.<ref name="jpldata" /> In 1909, it was first observed at Heidelberg Observatory as {{mp|A909 TC}}. The body's observation arc begins at Lowell Observatory in 1929, when it was identified as {{mp|1929 TG}}, 10 years prior to its official discovery observation at Turku.<ref name="MPC-Malmquista" />
== Physical characteristics ==
=== Rotation period ===
In September 2002, a first rotational lightcurve of Malmquista was obtained from photometric observations by Stephen Brincat at Flarestar Observatory on the island of Malta. Lightcurve analysis gave a well-defined rotation period of 14.077 hours with a brightness variation of 0.60 magnitude ({{small|U=3}}).<ref name="Brincat-2003" /> In September 2012, observations at the Palomar Transient Factory, California, gave a period of 14.044 hours and an amplitude of 0.42 magnitude ({{small|U=2}}).<ref name="Waszczak-2015" />
=== Spin axis ===
In 2013, an international study modeled a lightcurve with a period of 14.0591 hours and found a spin axis of (5.0°, 80.0°) in ecliptic coordinates (λ, β) ({{small|U=n.a.}}).<ref name="Hanus-2013c" />
=== Diameter and albedo ===
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Malmquista measures between 9.55 and 10.338 kilometers in diameter and its surface has an albedo between 0.220 and 0.307.<ref name="Masiero-2012" /><ref name="Masiero-2014" /><ref name="WISE" /> The ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.24 – derived from 8 Flora, a S-type asteroid and the family's largest member and namesake – and calculates a diameter of 10.80 kilometers with an absolute magnitude of 12.0.<ref name="lcdb" />
== Naming ==
This minor planet was named after Swedish astronomer Gunnar Malmquist (1893–1982), director of the Uppsala Astronomical Observatory in Sweden.<ref name="springer" /> The official {{MoMP|1527|naming citation}} was published by the Minor Planet Center in January 1956 ({{small|M.P.C. 1350}}).<ref name="DoMP-Circular-dates" />
== References == <references>
<ref name="jpldata">{{cite web |type = 2017-03-29 last obs. |title = JPL Small-Body Database Browser: 1527 Malmquista (1939 UG) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001527 |publisher = Jet Propulsion Laboratory |accessdate = 13 June 2017}}</ref>
<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names – (1527) Malmquista |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |page = 121 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_1528 |chapter = (1527) Malmquista }}</ref>
<ref name="MPC-Malmquista">{{cite web |title = 1527 Malmquista (1939 UG) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1527 |accessdate = 7 April 2017}}</ref>
<ref name="DoMP-Circular-dates">{{cite book |title = Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008) |year = 2009 |url = https://archive.org/details/dictionaryminorp2008schm |url-access = limited |chapter = Appendix – Publication Dates of the MPCs |last = Schmadel |first=Lutz D. |publisher = Springer Berlin Heidelberg |page = [https://archive.org/details/dictionaryminorp2008schm/page/n230 221] |isbn = 978-3-642-01964-7 |doi = 10.1007/978-3-642-01965-4}}</ref>
<ref name="Masiero-2014">{{cite journal |display-authors = 6 |first1 = Joseph R. |last1 = Masiero |first2 = T. |last2 = Grav |first3 = A. K. |last3 = Mainzer |first4 = C. R. |last4 = Nugent |first5 = J. M. |last5 = Bauer |first6 = R. |last6 = Stevenson |first7 = S. |last7 = Sonnett |date = August 2014 |title = Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014ApJ...791..121M |journal = The Astrophysical Journal |volume = 791 |issue = 2 |page = 11 |bibcode = 2014ApJ...791..121M |doi = 10.1088/0004-637X/791/2/121 |arxiv = 1406.6645 |access-date= 7 April 2017}}</ref>
<ref name="lcdb">{{cite LCDB|number = 1527 |accessdate = 7 April 2017}}</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 |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}}</ref>
<ref name="Masiero-2012">{{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 = C. |last6 = Nugent |first7 = M. S. |last7 = Cabrera |date = November 2012 |title = Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2012ApJ...759L...8M |journal = The Astrophysical Journal Letters |volume = 759 |issue = 1 |page = 5 |bibcode = 2012ApJ...759L...8M |doi = 10.1088/2041-8205/759/1/L8 |arxiv = 1209.5794 |access-date= 7 April 2017}}</ref>
<ref name="Brincat-2003">{{Cite journal |author = Brincat, Stephen M. |date = December 2002 |title = Rotation period and lightcurve of asteroid 1527 Malmquista |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2003MPBu...30...19B |journal = The Minor Planet Bulletin |volume = 30 |issue = 2 |page = 19 |issn = 1052-8091 |bibcode = 2003MPBu...30...19B |access-date= 7 April 2017}}</ref>
<ref name="Hanus-2013c">{{cite journal |display-authors = 6 |first1 = J. |last1 = Hanus |first2 = M. |last2 = Broz |first3 = J. |last3 = Durech |first4 = B. D. |last4 = Warner |first5 = J. |last5 = Brinsfield |first6 = R. |last6 = Durkee |first7 = D. |last7 = Higgins |first8 = R. A. |last8 = Koff |first9 = J. |last9 = Oey |first10 = F. |last10 = Pilcher |first11 = R. |last11 = Stephens |first12 = L. P. |last12 = Strabla |first13 = Q. |last13 = Ulisse |first14 = R. |last14 = Girelli |date = November 2013 |title = An anisotropic distribution of spin vectors in asteroid families |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2013A&A...559A.134H |journal = Astronomy and Astrophysics |volume = 559 |page = 19 |bibcode = 2013A&A...559A.134H |doi = 10.1051/0004-6361/201321993 |arxiv = 1309.4296 |access-date= 7 April 2017}}</ref>
<ref name="Waszczak-2015">{{cite journal |display-authors = 6 |first1 = Adam |last1 = Waszczak |first2 = Chan-Kao |last2 = Chang |first3 = Eran O. |last3 = Ofek |first4 = Russ |last4 = Laher |first5 = Frank |last5 = Masci |first6 = David |last6 = Levitan |first7 = Jason |last7 = Surace |first8 = Yu-Chi |last8 = Cheng |first9 = Wing-Huen |last9 = Ip |first10 = Daisuke |last10 = Kinoshita |first11 = George |last11 = Helou |first12 = Thomas A. |last12 = Prince |first13 = Shrinivas |last13 = Kulkarni |date = September 2015 |title = Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015AJ....150...75W |journal = The Astronomical Journal |volume = 150 |issue = 3 |page = 35 |bibcode = 2015AJ....150...75W |doi = 10.1088/0004-6256/150/3/75 |arxiv = 1504.04041 |access-date= 7 April 2017}}</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/NumberedMPs000001.html Discovery Circumstances: Numbered Minor Planets (1)-(5000)] – Minor Planet Center * {{AstDys|1527}} * {{JPL small body}}
{{Minor planets navigator |1526 Mikkeli |number=1527 |1528 Conrada}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Malmquista}} 001527 Category:Discoveries by Yrjö Väisälä Category:Named minor planets 19391018