1015 Christa

{{Short description|Asteroid}} {{Use dmy dates|date=March 2018}} {{Infobox planet | minorplanet = yes | name = 1015 Christa | background = #D6D6D6 | image = | image_size = | caption = | discovery_ref = <ref name="MPC-object" /> | discoverer = K. Reinmuth | discovery_site = Heidelberg Obs. | discovered = 31 January 1924 | mpc_name = (1015) Christa | alt_names = 1924 QF{{·}}A916 UE | pronounced = | named_after = unknown<ref name="springer" /> | mp_category = main-belt{{·}}{{small|(outer)}}<ref name="jpldata" /><ref name="lcdb" /> background<ref name="Ferret" /> | orbit_ref = <ref name="jpldata" /> | epoch = 23 March 2018 (JD 2458200.5) | uncertainty = 0 | observation_arc = 93.42 yr (34,123 d) | aphelion = 3.4848 AU | perihelion = 2.9262 AU | semimajor = 3.2055 AU | eccentricity = 0.0871 | period = 5.74 yr (2,096 d) | mean_anomaly = 232.16° | mean_motion = {{Deg2DMS|0.1717|sup=ms}} / day | inclination = 9.4449° | asc_node = 120.15° | arg_peri = 286.50°

| mean_diameter = {{val|82.350|1.096}} km<ref name="Masiero-2012" /> {{val|95.51|27.79}} km<ref name="Nugent-2016" /> {{val|96.592|2.896}} km<ref name="WISE" /> {{val|96.94|3.6}} km<ref name="SIMPS" /> {{val|99.88|36.30}} km<ref name="Nugent-2015" /> {{val|101.04|1.37}} km<ref name="AKARI" />

| mass = {{val|4.77|0.68|e=10|u=kg}}<ref name="Carry-2012" /> | density = {{val|9.17|1.46|ul=g/cm3}}<ref name="Carry-2012" /> | rotation = {{val|11.230|0.004|ul=h}}<ref name="Warner-2009k" />{{efn|name=lightcurve-plot-Warner}} {{val|12.189|0.001}} h<ref name="geneva-obs" />

| albedo = {{val|0.04|0.04}}<ref name="Nugent-2016" /><ref name="Nugent-2015" /> {{val|0.042|0.001}}<ref name="AKARI" /> {{val|0.0459|0.004}}<ref name="SIMPS" /> {{val|0.0463|0.0062}}<ref name="WISE" /> {{val|0.048|0.009}}<ref name="Masiero-2014" /> {{val|0.064|0.016}}<ref name="Masiero-2012" />

| spectral_type = Tholen {{=}} C<ref name="jpldata" /><ref name="lcdb" /> SMASS {{=}} X c<ref name="jpldata" /><ref name="Carry-2012" />{{·}}P<ref name="WISE" /> B–V {{=}} 0.693<ref name="jpldata" /> U–B {{=}} 0.320<ref name="jpldata" />

| abs_magnitude = 9.03<ref name="jpldata" /><ref name="lcdb" /><ref name="Masiero-2012" /><ref name="SIMPS" /><ref name="WISE" /><ref name="Nugent-2015" /><ref name="AKARI" /> 9.13<ref name="Nugent-2016" />{{·}}{{val|9.46|0.45}}<ref name="Veres-2015" /> }}

'''1015 Christa''', provisional designation {{mp|1924 QF}}, is a dark background asteroid from the outermost regions of the asteroid belt, approximately {{convert|96|km|mi|abbr=off|sp=us}} in diameter. It was discovered on 31 January 1924, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany.<ref name="MPC-object" /> The meaning of this asteroids's name is unknown.<ref name="springer" />

== Orbit and classification ==

Christa is a non-family asteroid from the main belt's background population.<ref name="Ferret" /> It orbits the Sun in the outermost asteroid belt at a distance of 2.9–3.5 AU once every 5 years and 9 months (2,096 days; semi-major axis of 3.21 AU). Its orbit has an eccentricity of 0.09 and an inclination of 9° with respect to the ecliptic.<ref name="jpldata" />

The asteroid was first observed as {{mp|A916 UE}} at the Simeiz Observatory in October 1916. The body's observation arc begins at Heidelberg in February 1924, two days after its official discovery observation.<ref name="MPC-object" />

== Physical characteristics ==

In the Tholen classification, Christa is a common C-type asteroid,<ref name="jpldata" /><ref name="lcdb" /> while in the SMASS classification, it is a Xc-subtype that transitions from the carbonaceous C-type to the X-type asteroids.<ref name="jpldata" /><ref name="Carry-2012" /> It has also been characterized as a primitive P-type asteroid by the Wide-field Infrared Survey Explorer (WISE).<ref name="WISE" />

=== Rotation period ===

In April 2005, a first rotational lightcurve of Christa was obtained from photometric observations by French amateur astronomers Raymond Poncy and René Roy. Lightcurve analysis gave a rotation period of 12.189 hours with a brightness variation of 0.20 magnitude ({{small|U=2}}).<ref name="geneva-obs" /> In January 2009, a refined period of 11.230 hours and an amplitude of 0.12 magnitude was measured by photometrist Brian Warner at his Palmer Divide Observatory in Colorado, United States ({{small|U=3-}}).<ref name="Warner-2009k" />{{efn|name=lightcurve-plot-Warner}}

=== Diameter and albedo ===

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, Christa measures between 82.35 and 101.04 kilometers in diameter and its surface has a low albedo between 0.04 and 0.064.<ref name="Masiero-2012" /><ref name="Nugent-2016" /><ref name="WISE" /><ref name="SIMPS" /><ref name="Nugent-2015" /><ref name="AKARI" /><ref name="Masiero-2014" /> The ''Collaborative Asteroid Lightcurve Link'' adopts the results obtained by IRAS, that is, an albedo of 0.0459 with a diameter of 96.94 kilometers based on an absolute magnitude of 9.03.<ref name="lcdb" />

1015 Christa has been observed to occult 8 stars between 2005 and 2023.

== Naming ==

Any reference of Christa's name to a person or occurrence is unknown.<ref name="springer" /> It is one of 120 minor planets for which no official naming citation has been published. All of these low-numbered asteroids have numbers between {{mp|{{MoMP|164|164 Eva}}}} and {{mp|{{MoMP|1514|1514 Ricouxa}}}} and were discovered between 1876 and the 1930s, predominantly by astronomers Auguste Charlois, Johann Palisa, Max Wolf and Karl Reinmuth.<ref name="DOMPN-unknown" />

== Notes == {{notelist|refs=

{{efn|name=lightcurve-plot-Warner|1={{usurped|1=[https://web.archive.org/web/20170321165743/http://www.minorplanetobserver.com/pdolc/A1015_2009.HTM Lightcurve plot of (1015) Christa]}}, Palmer Divide Observatory, ''B. D. Warner'' (2009). Summary figures at the [http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=1015%7CChrista LCDB]}}

}}

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

<ref name="jpldata">{{cite web |type = 2017-07-05 last obs. |title = JPL Small-Body Database Browser: 1015 Christa (1924 QF) |url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001015 |publisher = Jet Propulsion Laboratory |accessdate = 3 March 2018}}</ref>

<ref name="springer">{{cite book |title = Dictionary of Minor Planet Names – (1015) Christa |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |page = 87 |date = 2007 |isbn = 978-3-540-00238-3 |doi = 10.1007/978-3-540-29925-7_1016 |chapter = (1015) Christa }}</ref>

<ref name="DOMPN-unknown">{{cite book |title = Dictionary of Minor Planet Names – Fifth Revised and Enlarged revision |chapter = Appendix 11 – Minor Planet Names with Unknown Meaning |last = Schmadel | first = Lutz D. |publisher = Springer Berlin Heidelberg |pages = 927–929 |date = 2007 |isbn = 978-3-540-00238-3 |author-link= Lutz D. Schmadel}}</ref>

<ref name="MPC-object">{{cite web |title = 1015 Christa (1924 QF) |work = Minor Planet Center |url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1015 |accessdate = 3 March 2018}}</ref>

<ref name="geneva-obs">{{cite web |title = Asteroids and comets rotation curves – (1015) Christa |last = Behrend |first = Raoul |publisher = Geneva Observatory |url = http://obswww.unige.ch/~behrend/page3cou.html#001015 |accessdate = 3 March 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="Ferret">{{cite web |title = Asteroid 1015 Christa – Nesvorny HCM Asteroid Families V3.0 |work = Small Bodies Data Ferret |url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=1015+Christa |accessdate = 24 October 2019}}</ref>

<ref name="Carry-2012">{{Citation |first1 = B. |last1 = Carry |date = December 2012 |title = Density of asteroids |journal = Planetary and Space Science |volume = 73 |issue = 1 |pages = 98–118 |doi = 10.1016/j.pss.2012.03.009 |bibcode = 2012P&SS...73...98C |arxiv = 1203.4336 |s2cid = 119226456 }} See Table 1.</ref>

<ref name="lcdb">{{cite LCDB|number = 1015 |accessdate = 3 March 2018}}</ref>

<ref name="SIMPS">{{cite journal |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 |volume = 12 |pages = IRAS-A-FPA-3-RDR-IMPS-V6.0 |bibcode = 2004PDSS...12.....T |accessdate = 22 October 2019}}</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 |s2cid = 46350317 |access-date= 3 March 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 }}</ref>

<ref name="Nugent-2015">{{cite journal |display-authors = 6 |first1 = C. R. |last1 = Nugent |first2 = A. |last2 = Mainzer |first3 = J. |last3 = Masiero |first4 = J. |last4 = Bauer |first5 = R. M. |last5 = Cutri |first6 = T. |last6 = Grav |first7 = E. |last7 = Kramer |first8 = S. |last8 = Sonnett |first9 = R. |last9 = Stevenson |first10 = E. L. |last10 = Wright |date = December 2015 |title = NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015ApJ...814..117N |journal = The Astrophysical Journal |volume = 814 |issue = 2 |page = 13 |bibcode = 2015ApJ...814..117N |doi = 10.1088/0004-637X/814/2/117 |arxiv = 1509.02522 |s2cid = 9341381 |access-date= 3 March 2018}}</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= }} ([http://vizier.cfa.harvard.edu/viz-bin/VizieR-5?-source=J/PASJ/63/1117/acua_v1&Num=1015 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])</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="Warner-2009k">{{Cite journal |author = Warner, Brian D. |date = July 2009 |title = Asteroid Lightcurve Analysis at the Palmer Divide Observatory: 2008 December – 2009 March |url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2009MPBu...36..109W |journal = The Minor Planet Bulletin |volume = 36 |issue = 3 |pages = 109–116 |issn = 1052-8091 |bibcode = 2009MPBu...36..109W |access-date= 3 March 2018}}</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 |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 |s2cid = 53493339 |access-date= 3 March 2018}}</ref>

}}

== 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|1015}} * {{JPL small body}}

{{Minor planets navigator |1014 Semphyra |number=1015 |1016 Anitra}} {{Small Solar System bodies}} {{Authority control}}

{{DEFAULTSORT:Christa}} 001015 Category:Discoveries by Karl Wilhelm Reinmuth Category:Named minor planets 001015 001015 19240131