{{Short description|Main-belt asteroid}} {{Use dmy dates|date=September 2019}} {{Infobox planet | minorplanet = yes | name = 3700 Geowilliams | background = #D6D6D6 | image = | image_size = | caption = | discovery_ref = <ref name="MPC-object" /> | discoverer = C. Shoemaker<br />E. Shoemaker | discovery_site = Palomar Obs. | discovered = 23 October 1984 | mpc_name = (3700) Geowilliams | alt_names = {{mp|1984 UL|2}}{{·}}{{mp|1973 YF|2}}<br />1977 UJ | pronounced = | named_after = George E. Williams<ref name="MPC-object" /><br />{{small|(Australian geologist)}} | mp_category = {{nowrap|main-belt<ref name="MPC-object" /><ref name="jpldata" />{{·}}{{small|(inner)}}<ref name="lcdb" />}}<br />background<ref name="AstDys-object" /> | orbit_ref = <ref name="jpldata" /> | epoch = 23 March 2018 (JD 2458200.5) | uncertainty = 0 | observation_arc = 43.54 yr (15,902 d) | aphelion = 2.9602 AU | perihelion = 1.8695 AU | semimajor = 2.4148 AU | eccentricity = 0.2258 | period = 3.75 yr (1,371 d) | mean_anomaly = 293.18° | mean_motion = {{Deg2DMS|0.2626|sup=ms}} / day | inclination = 12.121° | asc_node = 289.16° | arg_peri = 153.06° | mean_diameter = {{val|7.712|0.130|ul=km}}<ref name="WISE" /><br />{{val|7.74|1.83|u=km}}<ref name="Nugent-2016" /><br />{{val|7.753|0.152|u=km}}<ref name="Masiero-2014" /><br />{{val|8.70|0.30|u=km}}<ref name="Masiero-2012" /><br />{{val|8.82|0.86|u=km}}<ref name="AKARI" /><br />{{val|8.97|u=km}} {{small|(calculated)}}<ref name="lcdb" /> | rotation = {{val|14.383|0.0183|ul=h}}<ref name="Waszczak-2015" /><br />{{val|14.387|0.003|u=h}}{{efn|name=lcdb-Higgins-2011}} | albedo = {{val|0.20}} {{small|(assumed)}}<ref name="lcdb" /><br />{{val|0.227|0.045}}<ref name="AKARI" /><br />{{val|0.23|0.13}}<ref name="Nugent-2016" /><br />{{val|0.233|0.033}}<ref name="Masiero-2012" /><br />{{val|0.2970|0.0516}}<ref name="WISE" /> | spectral_type = SMASS {{=}} S k<ref name="jpldata" /> | abs_magnitude = {{val|12.443|0.002}} {{small|(R)}}<ref name="Waszczak-2015" /><br />12.50<ref name="WISE" /><ref name="Masiero-2012" /><ref name="AKARI" /><br />12.6<ref name="jpldata" /><ref name="lcdb" /><br />12.89<ref name="Nugent-2016" /><br />{{val|12.94|0.46}}<ref name="Veres-2015" /> }}
'''3700 Geowilliams''', provisional designation {{mp|1984 UL|2}}, is a stony background asteroid from the inner regions of the asteroid belt, approximately {{convert|8|km|mi|abbr=off|sigfig=1|sp=us}} in diameter. It was discovered on 23 October 1984, by American astronomer couple Carolyn and Eugene Shoemaker at the Palomar Observatory in California, United States.<ref name="MPC-object" /> The S k-subtype has a rotation period of 14.38 hours. It was named for Australian geologist George E. Williams.<ref name="MPC-object" />
== Orbit and classification ==
''Geowilliams'' is a non-family asteroid from the main belt's background population.<ref name="AstDys-object" /> It orbits the Sun in the inner main-belt at a distance of 1.9–3.0 AU once every 3 years and 9 months (1,371 days; semi-major axis of 2.41 AU). Its orbit has an eccentricity of 0.23 and an inclination of 12° with respect to the ecliptic.<ref name="jpldata" /> The body's observation arc begins with its first observation as {{mp|1973 YF|2}} at Crimea-Nauchnij in December 1973, almost 11 years prior to its official discovery observation at Palomar.<ref name="MPC-object" />
== Physical characteristics ==
In the SMASS classification, ''Geowilliams'' is a Sk-subtype that transitions between the common S-type asteroid and the K-type asteroid. The latter spectral type is often found among members of the Eos family.<ref name="jpldata" />
=== Rotation period ===
In January 2008, a rotational lightcurve of ''Geowilliams'' was obtained from photometric observations by Australian amateur astronomer David Higgins at the Hunters Hill Observatory {{Obscode|E14}}. Lightcurve analysis gave a well-defined rotation period of 14.387 hours with a brightness variation of 0.40 magnitude ({{small|U=3}}).{{efn|name=lcdb-Higgins-2011}} In July 2010, a similar period of 14.383 hours and an amplitude of 0.42 was measured at the Palomar Transient Factory in California ({{small|U=2}}).<ref name="Waszczak-2015" />
=== Diameter and albedo ===
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, ''Geowilliams'' measures between 7.712 and 8.82 kilometers in diameter and its surface has an albedo between 0.227 and 0.297.<ref name="WISE" /><ref name="Nugent-2016" /><ref name="Masiero-2014" /><ref name="Masiero-2012" /><ref name="AKARI" />
The ''Collaborative Asteroid Lightcurve Link'' assumes a standard albedo for a stony asteroid of 0.20, and calculates a diameter of 8.97 kilometers based on an absolute magnitude of 12.6.<ref name="lcdb" />
== Naming ==
This minor planet was named after Australian geologist George E. Williams who discovered the Acraman crater when he worked for BHP in South Australia. The old 90-kilometer impact structure is one of the largest meteorite impact craters known on Earth and the largest one on the Australian continent.<ref name="MPC-object" /> The official naming citation was published by the Minor Planet Center on 2 February 1988 ({{small|M.P.C. 12810}}).<ref name="MPC-Circulars-Archive" />
== Notes == {{notelist|refs=
{{efn|name=lcdb-Higgins-2011|1=David Higgins (2011): rotation period {{val|14.387|0.003}} hours with a brightness amplitude of {{val|0.40|0.02}} mag. Quality code is 3. Summary figures for (3700) Geowilliams at the [http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=3700%7CGeowilliams LCDB] and archived website of the Hunters Hill Observatory by [https://web.archive.org/web/20080725094255/http://www.david-higgins.com/Astronomy/asteroid/lightcurves.htm David Higgins].}}
}} <!-- end of notelist -->
== References == {{reflist|30em|refs=
<ref name="jpldata">{{cite web |type = 2017-07-04 last obs. |title = JPL Small-Body Database Browser: 3700 Geowilliams (1984 UL2) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003700 |publisher = Jet Propulsion Laboratory |access-date = 14 May 2018}}</ref>
<ref name="MPC-object">{{cite web |title = 3700 Geowilliams (1984 UL2) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=3700 |access-date = 14 May 2018}}</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 = 14 May 2018}}</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 |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|s2cid = 119293330 }}</ref>
<ref name="AstDys-object">{{cite web |title = Asteroid 3700 Geowilliams – Proper Elements |publisher = AstDyS-2, Asteroids – Dynamic Site |url = https://newton.spacedys.com/astdys/index.php?pc=1.1.6&n=3700 |access-date= 29 October 2019}}</ref>
<ref name="lcdb">{{cite LCDB|number = 3700 |access-date = 14 May 2018}}</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 |s2cid = 35447010 }} ([http://iopscience.iop.org/0004-637X/741/2/68/fulltext/apj398969t1_mrt.txt catalog])</ref>
<ref name="AKARI">{{cite journal |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=3700 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])</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 |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|s2cid = 46350317 }}</ref>
<ref name="Nugent-2016">{{cite journal |display-authors = 6 |first1 = C. R. |last1 = Nugent |first2 = A. |last2 = Mainzer |first3 = J. |last3 = Bauer |first4 = R. M. |last4 = Cutri |first5 = E. A. |last5 = Kramer |first6 = T. |last6 = Grav |first7 = J. |last7 = Masiero |first8 = S. |last8 = Sonnett |first9 = E. L. |last9 = Wright |date = September 2016 |title = NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos |journal = The Astronomical Journal |volume = 152 |issue = 3 |page = 12 |bibcode = 2016AJ....152...63N |doi = 10.3847/0004-6256/152/3/63 |arxiv = 1606.08923 |doi-access = free }}</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 |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|s2cid = 8342929 }}</ref>
<ref name="Veres-2015">{{cite journal |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 |journal = Icarus |volume = 261 |pages = 34–47 |bibcode = 2015Icar..261...34V |doi = 10.1016/j.icarus.2015.08.007 |arxiv = 1506.00762|s2cid = 53493339 }}</ref>
}} <!-- end of reflist -->
== External links == * {{Cite web |url=http://www.david-higgins.com/Astronomy/asteroid/lightcurves.htm |title=Lightcurves by David Higgins |access-date=14 May 2018 |archive-url=https://web.archive.org/web/20101025031607/http://www.david-higgins.com/Astronomy/asteroid/lightcurves.htm |archive-date=25 October 2010 |url-status=dead }} * [https://www.adelaide.edu.au/directory/george.williams George E. Williams – University Staff Director], University of Adelaide * [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 * [https://www.minorplanetcenter.net/iau/lists/NumberedMPs000001.html Discovery Circumstances: Numbered Minor Planets (1)-(5000)] – Minor Planet Center * {{AstDys|3700}} * {{JPL small body}}
{{Minor planets navigator |3699 Milbourn |number=3700 |3701 Purkyně}} {{Small Solar System bodies}} {{Authority control}}
{{DEFAULTSORT:Geowilliams}} 003700 Category:Discoveries by Carolyn S. Shoemaker Category:Discoveries by Eugene Merle Shoemaker Category:Named minor planets 003700 19841023