View source for 3043 San Diego

{{Short description|Hungaria asteroid and slow rotator}}
{{Use dmy dates|date=October 2019}}
{{Infobox planet
 | minorplanet     = yes
 | name            = 3043 San Diego
 | background      = #D6D6D6
 | image           = 
 | image_size      = 
 | caption         = 
 | discovery_ref   = <ref name="jpldata" />
 | discovered      = 20 September 1982
 | discoverer      = [[Eleanor Helin|E. F. Helin]]
 | discovery_site  = [[Palomar Observatory|Palomar Obs.]]
 | mpc_name        = (3043) San Diego
 | alt_names       = 1982 SA{{·}}{{mp|1974 SQ|2}}
 | named_after     = [[San Diego]] {{small|(city)}}<ref name="springer" />
 | mp_category     = {{nowrap|[[main-belt]]<ref name="jpldata" />{{·}}[[Hungaria family|Hungaria]]<ref name="MPC-San Diego" /><ref name="lcdb" /><ref name="Spratt1990" />}}
 | orbit_ref       = <ref name="jpldata" />
 | epoch           = 4 September 2017 ([[Julian day|JD]] 2458000.5)
 | uncertainty     = 0
 | observation_arc = 41.90 yr (15,305 days)
 | aphelion        = 2.1323 [[Astronomical unit|AU]]
 | perihelion      = 1.7210 AU
 | semimajor       = 1.9266 AU
 | eccentricity    = 0.1067
 | period          = 2.67 [[Julian year (astronomy)|yr]] (977 days)
 | mean_anomaly    = 7.5114[[Degree (angle)|°]]
 | mean_motion     = {{Deg2DMS|0.3686|sup=ms}} / day
 | inclination     = 21.788°
 | asc_node        = 351.11°
 | arg_peri        = 31.747°
 | dimensions      = 4.62 km {{small|(calculated)}}<ref name="lcdb" /><br />{{val|4.771|0.022}} km<ref name="WISE" /><br />{{val|5.040|0.082}} km<ref name="Masiero-2014" />
 | rotation        = {{val|30.72|0.02}} [[Hour|h]] {{small|(wrong)}}<ref name="Warner-2005f" /><br />{{nowrap|{{val|105.7|0.1}} h {{small|(re-examined)}}<ref name="Warner-2009p" />}}
 | albedo          = {{val|0.252|0.048}}<ref name="Masiero-2014" /><br />{{val|0.2817|0.0408}}<ref name="WISE" /><br />0.30 {{small|(assumed)}}<ref name="lcdb" />
 | spectral_type   = [[E-type asteroid|E]]<ref name="lcdb" />
 | abs_magnitude   = 13.6<ref name="jpldata" /><ref name="WISE" />{{·}}13.7<ref name="lcdb" />
}}

'''3043 San Diego''', provisional designation {{mp|1982 SA}}, is a stony Hungaria [[asteroid]] and [[List of slow rotators (minor planets)|slow rotator]] from the inner regions of the [[asteroid belt]], approximately 4.7 kilometers in diameter.

It was discovered by American astronomer [[Eleanor Helin]] on 30 September 1982, at the U.S. [[Palomar Observatory]] in California, and named for the city of [[San Diego]].<ref name="springer" /><ref name="MPC-San Diego" />

== Classification and orbit ==

The bright [[E-type asteroid]] is a member of the [[Hungaria family]], which form the [[Kirkwood gap|innermost]] dense concentration of asteroids in the [[Solar System]]. The asteroid orbits the Sun at a distance of 1.7–2.1&nbsp;[[Astronomical unit|AU]] once every 2 years and 8 months (977 days). Its orbit has an [[orbital eccentricity|eccentricity]] of 0.11 and an [[orbital inclination|inclination]] of 22[[Degree (angle)|°]] with respect to the [[ecliptic]].<ref name="jpldata" /> The first observation was taken at [[Crimea–Nauchnij]] in 1974, extending the asteroid's [[observation arc]] by 8 years prior to its discovery.<ref name="MPC-San Diego" />

== Slow rotator ==

San Diego is a [[List of slow rotators (minor planets)|slow rotator]]. In March 2005, a rotational [[lightcurve]] was obtained from [[Photometry (astronomy)|photometric]] observations by American astronomer [[Brian D. Warner|Brian Warner]] at his Palmer Divide Observatory ({{small|[[IAU code#716|716]]}}) in Colorado. It gave a long [[rotation period]] of {{val|105.7}} hours with a brightness variation of 0.60 in [[Magnitude (astronomy)|magnitude]] ({{small|[[LCDB quality code|U=3-]]}}). The period was derived from a re-examined lightcurve that originally gave a much shorter period of {{val|30.72|0.02}} hours with an amplitude of 0.37 in magnitude ({{small|[[LCDB quality code|U=0]]}}).<ref name="Warner-2005f" /> This previously published period was only preliminary and is now considered wrong upon re-examination.<ref name="lcdb" />

== Diameter and albedo ==

According to the survey carried out by the [[NEOWISE]] mission of NASA's [[Wide-field Infrared Survey Explorer]], San Diego measures 4.8 and 5.0 kilometers in diameter and its surface has an albedo of 0.25 and 0.28, respectively,<ref name="WISE" /><ref name="Masiero-2014" /> while the ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.30 – a compromise value between 0.4 and 0.2, corresponding to the Hungaria asteroids both as family and orbital group – and calculates a diameter of 4.6 kilometers with an [[absolute magnitude]] of 13.7.<ref name="lcdb" />

== Naming ==

This [[minor planet]] was named for the city of [[San Diego]], California, in appreciation of the city council's efforts to reduce the local light pollution {{crossreference|(see [[dark-sky movement]])}}. Palomar mountain is located within [[San Diego County, California|San Diego County]], California, and the astronomers at the site were concerned that the [[light pollution]] from the city would ruin their ability to use the observatory. The council had voted to use Low-Pressure Sodium ([[Sodium vapor lamp|LPS]]) vapor lamps for their street lights. This fixture only emitted light at one [[wavelength]], which astronomers could readily filter out.<ref name="springer" /> The approved naming citation was published by the [[Minor Planet Center]] on 13 July 1984 ({{small|[[Minor Planet Circulars|M.P.C.]] 8914}}).<ref name="MPC-Circulars-Archive" />

== References ==
{{reflist|30em|refs=

<ref name="jpldata">{{cite web
  |type       = 2016-08-15 last obs.
  |title      = JPL Small-Body Database Browser: 3043 San Diego (1982 SA)
  |url        = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003043
  |archive-url = https://web.archive.org/web/20200915032256/https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2003043
  |url-status = dead
  |archive-date = 15 September 2020
  |publisher  = [[Jet Propulsion Laboratory]]
  |access-date = 3 July 2017}}</ref>

<ref name="springer">{{cite book
  |title      = Dictionary of Minor Planet Names – (3043) San Diego
  |last       = Schmadel | first = Lutz D.
  |publisher  = [[Springer Berlin Heidelberg]]
  |page       = 251
  |date       = 2007
  |isbn       = 978-3-540-00238-3
  |doi       = 10.1007/978-3-540-29925-7_3044 |chapter       = (3043) San Diego }}</ref>

<ref name="MPC-San Diego">{{cite web
  |title      = 3043 San Diego (1982 SA)
  |work       = Minor Planet Center
  |url        = https://www.minorplanetcenter.net/db_search/show_object?object_id=3043
  |access-date = 21 August 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 = 21 August 2016}}</ref>

<ref name="lcdb">{{cite web
  |title      = LCDB Data for (3043) San Diego
  |publisher  = Asteroid Lightcurve Database (LCDB)
  |url        = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=3043%7CSan%20Diego
  |access-date = 21 August 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
  |access-date= 21 August 2016}}</ref>

<ref name="Warner-2005f">{{cite journal
  |author     = Warner, Brian D.
  |date       = September 2005
  |title      = Asteroid lightcurve analysis at the Palmer Divide Observatory - winter 2004-2005
  |url        = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2005MPBu...32...54W
  |journal    = The Minor Planet Bulletin
  |volume     = 32
  |issue      = 3
  |pages      = 54–58
  |issn       = 1052-8091
  |bibcode    = 2005MPBu...32...54W
  |access-date= 7 January 2016}}</ref>

<ref name="Warner-2009p">{{cite journal
  |first1     = Brian D. |last1 = Warner
  |first2     = Robert, D. |last2 = Stephens
  |first3     = Alan W. |last3 = Harris
  |first4     = Petr |last4 = Pravec
  |date       = October 2009
  |title      = A Re-examination of the Lightcurves for Seven Hungaria Asteroids
  |url        = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2009MPBu...36..176W
  |journal    = The Minor Planet Bulletin
  |volume     = 36
  |issue      = 4
  |pages      = 176–179
  |issn       = 1052-8091
  |bibcode    = 2009MPBu...36..176W
  |access-date= 7 January 2016}}</ref>

<ref name="Spratt1990">{{cite journal
  | author=Spratt, Christopher E.
  | title=The Hungaria group of minor planets
  | journal=Journal of the Royal Astronomical Society of Canada
  | issn=0035-872X
  | date=April 1990
  | volume=84
  | issue=2
  | pages=123–131
  | bibcode=1990JRASC..84..123S}}</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= 6 December 2016}}</ref>

}} <!-- end of reflist -->

==Further reading==
{{refbegin}}
* [[Curtis Peebles]], ''Asteroids: A History'', 2000, Smithsonian Institution, {{ISBN|1-56098-389-2}}.
{{refend}}

== External links ==
* {{YouTube|id=3Kn3s98KRYw|title=The Palmer Divide Observatory: ''Tour given by Brian Warner''}} {{small|(time 4:03 min.)}}
* [http://www.minorplanetobserver.com/pdolc/A3043_2005.HTM Lightcurve plot of 3043 San Diego], Palmer Divide Observatory, [[Brian D. Warner|B. D. Warner]] (2005)
* [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|3043}}
* {{JPL small body}}

{{Minor planets navigator |3042 Zelinsky |number=3043 |3044 Saltykov}}
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{{DEFAULTSORT:San Diego}}
[[Category:Hungaria asteroids|003043]]
[[Category:Discoveries by Eleanor F. Helin]]
[[Category:Named minor planets]]
[[Category:Slow rotating minor planets|003043]]
[[Category:Astronomical objects discovered in 1982|19820920]]