1447 Utra
{{Short description|Stony asteroid, slow rotator and suspected tumbler}}
{{Use dmy dates|date=October 2019}}
{{Infobox planet
| minorplanet = yes
| name = 1447 Utra
| background = #D6D6D6
| image =
| image_size =
| caption =
| discovered = 26 January 1938
| discoverer = Y. Väisälä
| discovery_site = Turku Obs.
| mpc_name = (1447) Utra
| alt_names = 1938 BB{{·}}1936 SB
1951 KO{{·}}A918 FA
| named_after = Utra {{small|(Finnish town)}}
| mp_category = main-belt{{·}}{{small|(middle)}}
| epoch = 4 September 2017 (JD 2458000.5)
| uncertainty = 0
| observation_arc = 98.67 yr (36,038 days)
| aphelion = 2.6404 AU
| perihelion = 2.4299 AU
| semimajor = 2.5352 AU
| eccentricity = 0.0415
| period = 4.04 yr (1,474 days)
| mean_anomaly = 285.64°
| mean_motion = {{Deg2DMS|0.2442|sup=ms}} / day
| inclination = 4.7865°
| asc_node = 35.528°
| arg_peri = 64.085°
| dimensions = {{val|11.83|0.86}} km
{{val|11.834|0.122}} km
{{val|12.634|0.103}} km
{{val|13.26|0.53}} km
13.58 km {{small|(calculated)}}
| rotation = {{val|257|30}} h{{efn|name=LCDB-Martinez-2011}}
| albedo = 0.20 {{small|(assumed)}}
{{val|0.303|0.038}}
{{val|0.3381|0.0591}}
{{val|0.381|0.058}}
| spectral_type = S
| abs_magnitude = 11.30{{·}}{{val|11.60|0.44}}{{·}}11.7
}}
1447 Utra, provisional designation {{mp|1938 BB}}, is a stony asteroid, slow rotator and suspected tumbler from the central region of the asteroid belt, approximately 12 kilometers in diameter. It was discovered on 26 January 1938, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland. The asteroid was named for the Finnish town of Utra (now a part of Joensuu).
Orbit and classification
Utra is a S-type asteroid. It orbits the Sun in the central main-belt at a distance of 2.4–2.6 AU once every 4.04 years (1,474 days). Its orbit has an eccentricity of 0.04 and an inclination of 5° with respect to the ecliptic. Utra was first identified as {{mp|A918 FA}} at Heidelberg Observatory in 1918. The body's observation arc begins with its official discovery observation at Turku in 1938.
Physical characteristics
= Slow rotator =
In March 2011, a rotational lightcurve of Utra was obtained from photometric observations by astronomer Luis E. Martinez. Lightcurve analysis gave a long rotation period of 257 hours with a brightness variation of 0.63 magnitude ({{small|U=2}}). This slow rotator is also a suspected tumbler (T0).{{efn|name=LCDB-Martinez-2011}}
= Diameter and albedo =
According to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Utra measures between 11.83 and 13.26 kilometers in diameter, and its surface has an albedo between 0.303 and 0.381. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 13.58 kilometers with an absolute magnitude of 11.7.
Naming
This minor planet was named for Utra, a northeastern Finnish town and birthplace of the discoverer. The official {{MoMP|1447|naming citation}} was published by the Minor Planet Center on 30 January 1964 ({{small|M.P.C. 2277}}).
Notes
{{notelist|refs=
{{efn|name=LCDB-Martinez-2011|1=Martinez (2011) web: rotation period {{val|257|30}} hours with a brightness amplitude of {{val|0.63}} mag. Summary figures for (1447) Utra at [http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=1447%7CUtra Collaborative Asteroid Lightcurve Link (CALL)]. The [http://lenomiyaobs.org/Blank.html referenced website] was a non-recoverable dead link.}}
}}
References
{{reflist|30em|refs=
|type = 2016-11-14 last obs.
|title = JPL Small-Body Database Browser: 1447 Utra (1938 BB)
|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001447
|publisher = Jet Propulsion Laboratory
|accessdate = 25 July 2017}}
|title = Dictionary of Minor Planet Names – (1447) Utra
|last = Schmadel | first = Lutz D.
|publisher = Springer Berlin Heidelberg
|page = 116
|date = 2007
|isbn = 978-3-540-00238-3
|doi = 10.1007/978-3-540-29925-7_1448 |chapter = (1447) Utra }}
|title = 1447 Utra (1938 BB)
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=1447
|accessdate = 4 January 2017}}
|title = Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008)
|chapter = Appendix – Publication Dates of the MPCs
|last = Schmadel |first=Lutz D.
|publisher = Springer Berlin Heidelberg
|page = 221
|isbn = 978-3-642-01964-7
|doi = 10.1007/978-3-642-01965-4}}
|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= 4 January 2017}}
|title = LCDB Data for (1447) Utra
|publisher = Asteroid Lightcurve Database (LCDB)
|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=1447%7CUtra
|accessdate = 4 January 2017}}
|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=1447 online], [https://core.ac.uk/download/pdf/43545172.pdf AcuA catalog p. 153])
|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}}
|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= 4 January 2017}}
|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
|access-date= 4 January 2017}}
}}
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|1447}}
- {{JPL small body}}
{{Minor planets navigator |1446 Sillanpää |number=1447 |1448 Lindbladia}}
{{Small Solar System bodies}}
{{Authority control}}
{{DEFAULTSORT:Utra}}