9965 GNU
{{Short description|Asteroid}}
{{Use dmy dates|date=May 2018}}
{{Infobox planet
| minorplanet = yes
| name = 9965 GNU
| background = #D6D6D6
| image = AnimatedOrbitOf9965GNU.gif
| image_scale =
| caption = Orbits of GNU (blue), the inner planets and Jupiter (outermost)
| discoverer = Spacewatch
| discovery_site = {{nowrap|Kitt Peak National Obs.}}
| discovered = 5 March 1992
| mpc_name = (9965) GNU
| alt_names = {{mp|1992 EF|2}}{{·}}{{mp|1988 BD|4}}
{{mp|1993 QR|3}}
| pronounced =
| named_after = GNU Project
{{small|(free software project)}}
| mp_category = main-belt{{·}}{{small|(inner)}}
background
| epoch = 23 March 2018 (JD 2458200.5)
| uncertainty = 0
| observation_arc = 30.17 yr (11,019 d)
| aphelion = 2.8283 AU
| perihelion = 2.0080 AU
| semimajor = 2.4181 AU
| eccentricity = 0.1696
| period = 3.76 yr (1,373 d)
| mean_anomaly = 276.39°
| mean_motion = {{Deg2DMS|0.2621|sup=ms}} / day
| inclination = 12.206°
| asc_node = 156.48°
| arg_peri = 82.938°
| mean_diameter = {{val|2.07|0.53|ul=km}}
{{val|4.10|u=km}} {{small|(calculated)}}
{{val|6.22|2.14|u=km}}
{{val|6.293|0.159|u=km}}
| rotation = {{val|39.720|0.1589|ul=h}} {{small|(R)}}
{{val|39.745|0.1589|u=h}} {{small|(S)}}
| albedo = {{val|0.102|0.014}}
{{val|0.1022|0.0145}}
{{val|0.105|0.125}}
{{val|0.20}} {{small|(assumed)}}
{{val|0.53|0.12}}
| spectral_type = D {{small|(Pan-STARRS)}}
S {{small|(SDSS-MOC)}}
S {{small|(assumed)}}
| abs_magnitude = 14.10
14.3
{{val|14.31|0.14}}
{{val|14.398|0.005}} {{small|(R)}}
14.72
{{val|14.966|0.011}} {{small|(S)}}
}}
9965 GNU, provisional designation {{mp|1992 EF|2}}, is a background asteroid from the inner regions of the asteroid belt, approximately {{convert|4|km|mi|abbr=off|sigfig=1|sp=us}} in diameter. It was discovered on 5 March 1992, by astronomer of the Spacewatch program at the Kitt Peak National Observatory in Arizona, United States. The uncertain D-type asteroid has a long rotation period of 39.7 hours. It was named for the free-software GNU Project.
Orbit and classification
GNU is a non-family asteroid from the main belt's background population.
It orbits the Sun in the inner asteroid belt at a distance of 2.0–2.8 AU once every 3 years and 9 months (1,373 days; semi-major axis of 2.42 AU). Its orbit has an eccentricity of 0.17 and an inclination of 12° with respect to the ecliptic. The body's observation arc begins with its first observation as {{mp|1988 BD|4}} at La Silla Observatory in January 1988, or 4 years prior to its official discovery observation at Kitt Peak.
Physical characteristics
GNU has been characterized as a dark D-type asteroid by Pan-STARRS{{'}} survey and in the SDSS-based taxonomy. It is also an assumed S-type asteroid, the most common type in the inner asteroid belt.
= Rotation period =
In September and October 2012, two rotational lightcurves of GNU were obtained from photometric observations by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 39.720 and 39.745 hours, with a brightness amplitude of 0.36 and 0.42 magnitude in the R- and S-band, respectively ({{small|U=2/2}}). While not being a slow rotator, GNU{{'}} period is significantly longer than the average spin rate of 2 to 20 hours, seen among the majority of asteroids.
= Diameter and albedo =
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, GNU measures between 2.07 and 6.293 kilometers in diameter and its surface has an albedo between 0.102 and 0.53. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20 and calculates a diameter of 4.10 kilometers based on an absolute magnitude of 14.3.
Naming
This minor planet was named for the free-software GNU Project, created by Richard Stallman 1984. GNU is the recursive acronym for "GNU is not Unix". The collaborative projects enables programmers to trade and improve upon free software. The official naming citation was published by the Minor Planet Center on 11 November 2000 ({{small|M.P.C. 41571}}).
References
{{reflist|30em|refs=
|type = 2018-03-22 last obs.
|title = JPL Small-Body Database Browser: 9965 GNU (1992 EF2)
|url = https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2009965
|publisher = Jet Propulsion Laboratory
|access-date = 28 May 2018}}
|title = 9965 GNU (1992 EF2)
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/db_search/show_object?object_id=9965
|access-date = 28 May 2018}}
|title = MPC/MPO/MPS Archive
|work = Minor Planet Center
|url = https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html
|access-date = 28 May 2018}}
|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
|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|s2cid = 118745497 }}
|title = Asteroid 9965 GNU
|work = Small Bodies Data Ferret
|url = https://sbntools.psi.edu/ferret/SimpleSearch/results.action?targetName=9965+GNU
|access-date = 28 May 2018}}
|first1 = J. M. |last1 = Carvano
|first2 = P. H. |last2 = Hasselmann
|first3 = D. |last3 = Lazzaro
|first4 = T. |last4 = Mothé-Diniz
|date = February 2010
|title = SDSS-based taxonomic classification and orbital distribution of main belt asteroids
|url = https://sbnarchive.psi.edu/pds3/non_mission/EAR_A_I0035_5_SDSSTAX_V1_1/data/sdsstax_ast_table.tab
|journal = Astronomy and Astrophysics
|volume = 510
|page = 12
|bibcode = 2010A&A...510A..43C
|doi = 10.1051/0004-6361/200913322
|access-date= 30 October 2019|doi-access= free
}} [https://sbn.psi.edu/pds/resource/sdsstax.html (PDS data set)]
|title = LCDB Data for (9965) GNU
|publisher = Asteroid Lightcurve Database (LCDB)
|url = http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=9965%7CGNU
|access-date = 28 May 2018}}
|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 }}
|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 }}
|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])
|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 }}
|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 }}
}}
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
- [https://www.minorplanetcenter.net/iau/lists/NumberedMPs005001.html Discovery Circumstances: Numbered Minor Planets (5001)-(10000)] – Minor Planet Center
- {{AstDys|9965}}
- {{JPL small body}}
{{Minor planets navigator |9964 Hideyonoguchi |number=9965 |(9966) 1992 ES13}}
{{Small Solar System bodies}}
{{Authority control}}
{{DEFAULTSORT:GNU}}