4606 Saheki
{{Short description|Main belt asteroid}}
{{Use dmy dates|date=October 2019}}
{{Infobox planet
| minorplanet = yes
| name = 4606 Saheki
| background = #D6D6D6
| image = 4606Saheki (Lightcurve Inversion).png
| image_scale =
| caption = {{longitem|Lightcurve-based 3D-model of Saheki|style=padding: 5px 0;}}
| discovered = 27 October 1987
| discoverer = T. Seki
| discovery_site = Geisei Obs.
| mpc_name = (4606) Saheki
| alt_names = {{mp|1987 UM|1}}{{·}}{{mp|1972 GA|1}}
{{mp|1977 TJ|7}}{{·}}{{mp|1977 VF|2}}
{{mp|1982 FH|4}}
| named_after = {{nowrap|Tsuneo Saheki {{small|(astronomer)}}}}
| mp_category = main-belt{{·}}Flora
| epoch = 4 September 2017 (JD 2458000.5)
| uncertainty = 0
| observation_arc = 63.81 yr (23,305 days)
| aphelion = 2.4805 AU
| perihelion = 2.0231 AU
| semimajor = 2.2518 AU
| eccentricity = 0.1016
| period = 3.38 yr (1,234 days)
| mean_anomaly = 202.74°
| mean_motion = {{Deg2DMS|0.2917|sup=ms}} / day
| inclination = 2.6338°
| asc_node = 241.26°
| arg_peri = 251.92°
| dimensions = {{val|6.655|0.069}}
{{val|6.712|0.041}} km
7.14 km {{small|(calculated)}}
| rotation = {{val|4.969|0.003}} h{{efn|name=lcdb-Higgins}}
{{val|4.97347|0.00005}} h
{{val|5.032|0.001}} h
| albedo = 0.24 {{small|(assumed)}}
{{val|0.3266|0.0245}}
{{val|0.332|0.088}}
| spectral_type = S
| abs_magnitude = 12.7{{·}}13.0{{·}}{{val|13.35|0.32}}
}}
4606 Saheki, provisional designation {{mp|1987 UM|1}}, is a stony Flora asteroid from the inner regions of the asteroid belt, approximately 7 kilometers in diameter.
The asteroid was discovered on 27 October 1987, by Japanese astronomer Tsutomu Seki at Geisei Observatory, Japan. It was later named after Japanese astronomer Tsuneo Saheki.
Classification and orbit
Saheki is a member of the Flora family, one of the largest families of stony asteroids. It orbits the Sun in the inner main-belt at a distance of 2.0–2.5 AU once every 3 years and 5 months (1,234 days). Its orbit has an eccentricity of 0.10 and an inclination of 3° with respect to the ecliptic. The first precovery was taken at Palomar Observatory in 1953, extending the asteroid's observation arc by 34 years prior to its discovery.
Physical characteristics
= Rotation period =
In January 2009, a rotational lightcurve of Saheki was obtained from photometric observations by David Higgins at Hunters Hill Observatory, Australia. Lightcurve analysis rendered a well-defined rotation period of {{val|4.969}} hours with a brightness variation of 0.56 in magnitude ({{small|U=3}}).{{efn|name=lcdb-Higgins}}
Two months later, in March 2009, a second lightcurve was obtained at the Via Capote Observatory {{Obscode|G69}}, California. It gave a period of {{val|5.032}} and an amplitude of 0.68 in magnitude ({{small|U=3-}}).
= Spin axis =
In 2013, an international study modeled a lightcurve with a concurring period of 4.97347 hours and found a spin axis of (44.0°, 59.0°) and (222.0°, 68.0°) in ecliptic coordinates (λ, β), respectively ({{small|Q=2}}).
= Diameter and albedo =
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Saheki has a high albedo of 0.33 and a diameter of 6.7 kilometers, while the Collaborative Asteroid Lightcurve Link calculates a diameter of 7.1 kilometers, based on an assumed albedo of 0.24, derived from 8 Flora, the Flora family's namesake and largest member.
Naming
This minor planet was named after Japanese astronomer and president of the Toa Astronomical Society, Tsuneo Saheki (1916–1996). Over half a century, Saheki as gathered large inventory of observational data of the planet Mars. The Martian crater Saheki is also named in his honour. The official naming citation was published by the Minor Planet Center on 28 May 1991 ({{small|M.P.C. 18308}}).
Notes
{{notelist|refs=
{{efn|name=lcdb-Higgins|1=Higgins (2011) web: rotation period {{val|4.969|0.003}} hours with a brightness amplitude of {{val|0.56}} mag. The Collaborative Asteroid Lightcurve Link assigns a quality code of U=3 to the period solution, which denotes a secure result within the precision given and no ambiguity. Summary figures for (4606) Saheki at [http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=4606%7CSaheki Collaborative Asteroid Lightcurve Link (CALL)]}}
}}
References
{{reflist|30em|refs=
|type = 2017-06-06 last obs.
|title = JPL Small-Body Database Browser: 4606 Saheki (1987 UM1)
|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004606
|publisher = Jet Propulsion Laboratory
|access-date = 20 June 2017}}
|title = Dictionary of Minor Planet Names – (4606) Saheki
|last = Schmadel | first = Lutz D.
|publisher = Springer Berlin Heidelberg
|page = 396
|date = 2007
|isbn = 978-3-540-00238-3
|doi = 10.1007/978-3-540-29925-7_4531 |chapter = (4606) Saheki }}
|title = 4606 Saheki (1987 UM1)
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=4606
|access-date = 23 January 2016}}
|title = MPC/MPO/MPS Archive
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html
|access-date = 17 May 2016}}
|title = LCDB Data for (4606) Saheki
|publisher = Asteroid Lightcurve Database (LCDB)
|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=4606%7CSaheki
|access-date = 23 January 2016}}
|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= 23 January 2016}}
|author = Brinsfield, James W.
|date = July 2009
|title = Asteroid Lightcurve Analysis at the Via Capote Observatory: 2009 1st Quarter
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2009MPBu...36..127B
|journal = The Minor Planet Bulletin
|volume = 36
|issue = 3
|pages = 127–128
|issn = 1052-8091
|bibcode = 2009MPBu...36..127B
|access-date= 23 January 2016}}
|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= 23 January 2016}}
|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= 26 April 2016}}
|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 = J. |last6 = Dailey
|first7 = P. R. M. |last7 = Eisenhardt
|first8 = R. S. |last8 = McMillan
|first9 = T. B. |last9 = Spahr
|first10 = M. F. |last10 = Skrutskie
|first11 = D. |last11 = Tholen
|first12 = R. G. |last12 = Walker
|first13 = E. L. |last13 = Wright
|first14 = E. |last14 = DeBaun
|first15 = D. |last15 = Elsbury
|first16 = T. IV |last16 = Gautier
|first17 = S. |last17 = Gomillion
|first18 = A. |last18 = Wilkins
|date = November 2011
|title = Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters
|url = http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...68M
|journal = The Astrophysical Journal
|volume = 741
|issue = 2
|page = 20
|bibcode = 2011ApJ...741...68M
|doi = 10.1088/0004-637X/741/2/68
|arxiv = 1109.4096
|access-date= 5 December 2016}}
}}
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|4606}}
- {{JPL small body}}
{{Minor planets navigator |4605 Nikitin |number=4606 |4607 Seilandfarm}}
{{Small Solar System bodies}}
{{Authority control}}
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