|
Gwrthrych traws-Neifionaidd yw '''(486958) 2014 MU<sub>69</sub>''', sydd a'r llysenw '''Ultima Thule''', wedi ei leoli yng [[Gwregys Kuiper|wregys Kuiper]]. Mae ei siâp yn hirfain, ac mae'n bosib ei fod yn gorff dwbl neu gysylltiol, gyda diamedr wedi ei amcangyfrif tua 30 cilomedr (20 milltir). Gyda cyfnod cylchdroadol o 295 blwyddyn a gogwydd ac echreiddiad isel, mae'n cael ei ddosbarthu fel gwrthrych gwregys Kuiper clasurol a tybir nad yw wedi profi unrhyw aflonyddiad sylweddol gyda nifer cymhedrol o geudyllau.
{{DISPLAYTITLE:{{mp|(486958) 2014 MU|69}}}}
{{Infobox planet|minorplanet=yes|name={{mp|(486958) 2014 MU|69}}|background=#C2E0FF|image=Detecting Ultima Thule's Size and Shape on Approach (cropped).png|alt=|caption={{mp|2014 MU|69}} in greyscale{{Efn|Photograph taken by the [[Long Range Reconnaissance Imager]] aboard ''[[New Horizons]]'' on 31 December 2018, displaying {{mp|2014 MU|69}}'s "bowling pin" shape.<ref name="explored">{{Cite web|author=[[Johns Hopkins University Applied Physics Laboratory]]|title=New Horizons Successfully Explores Ultima Thule |url=http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20190101|website=[[New Horizons]]|accessdate=1 January 2019|archiveurl=https://web.archive.org/web/20190101164301/http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20190101|archivedate=1 January 2019|date=1 January 2019}}</ref>}}|discovery_ref= <ref name="jpldata" /><ref name="MPC-486958" />|discovered=26 June 2014|discoverer={{nowrap|[[Hubble Space Telescope]]}}|discovery_site=[[Orbit|Earth's orbit]]|mpc_name={{mp|(486958) 2014 MU|69}}|alt_names={{Hlist|Ultima Thule {{small|(unofficial)}}<ref name="Ultima Thule" />|PT1<ref name="NASA-new-target-2015" />|1110113Y<ref name="Lakdawalla2014" />|Object 11<ref name="Buie" />}}|mp_category={{Hlist|[[Trans-Neptunian object|TNO]]<ref name="jpldata" />|[[Classical Kuiper belt object|cubewano]]<ref name="Lakdawalla2014" /><ref name="Buie-DES"/>|[[Distant minor planet|distant]]<ref name="MPC-486958" />}}|orbit_ref=<ref name="MPC-486958" />|epoch=2019 April 27([[Julian day|JD]] 2458600.5)|uncertainty=2|observation_arc=851 days|aphelion={{val|46.442||u=AU}}|perihelion={{val|42.7212447|0.0014309|u=AU}}|semimajor={{val|44.5813998||u=AU}}|eccentricity={{val|0.0417249|0.0000346}}|period={{val|298}} [[Julian year (astronomy)|yr]]|mean_anomaly={{val|316.55086||u=°}}|mean_motion={{Deg2DMS|0.00331110|sup=ms}} / day|inclination={{val|2.45116|0.000012|u=°}}|asc_node={{val|158.99773|0.00045|u=°}}|arg_peri={{val|174.418|0.037|u=°}}|dimensions={{val|20|u=km}} and {{val|18|u=km}}<ref name="NH-2017" /><br />{{small|(as [[Contact binary (small Solar System body)|contact]]/[[Binary asteroid|binary system]])}}|mean_diameter={{val|30|u=km}}<ref name="NH-2017" />|rotation=|albedo=0.04–0.10 {{small|(assumed)}}<ref name="Lakdawalla2014" /><br />0.04–0.15 {{small|(assumed)}}<ref name="Buie" />|spectral_type=|magnitude=26.8<ref name="Lakdawalla2015" />|abs_magnitude=11.1<ref name="MPC-486958" />}}Gwrthrych traws-Neifionaidd yw '''(486958) 2014 MU<sub>69</sub>''', sydd a'r llysenw '''Ultima Thule''', wedi ei leoli yng [[Gwregys Kuiper|wregys Kuiper]]. Mae ei siâp yn hirfain, ac mae'n bosib ei fod yn gorff dwbl neu gysylltiol, gyda diamedr wedi ei amcangyfrif tua 30 cilomedr (20 milltir). Gyda cyfnod cylchdroadol o 295 blwyddyn a gogwydd ac echreiddiad isel, mae'n cael ei ddosbarthu fel gwrthrych gwregys Kuiper clasurol a tybir nad yw wedi profi unrhyw aflonyddiad sylweddol gyda nifer cymhedrol o geudyllau.
Darganfuwyd '''2014 MU<sub>69</sub>''' ar 26 Mehefin 2014 gan seryddwyr yn defnyddio [[Telesgop Gofod Hubble]] fel rhan o archwiliad y gwregys Kuiper belt am wrthrych i'w dargedu gan daith ''[[New Horizons]]'' fel rhan o'i daith estynedig ar ôl ymweld a [[Plwton (planed gorrach)|Phlwton]]. Cafodd ei ddewis yn hytrach na'r targedau 2014 OS393 a 2014PN70 i ddod yn darged sylfaenol y daith. Mae ei lysenw, yn drosiad Lladin am le wedi'i leoli y tu hwnt i ffiniau y byd hysbys, a'i ddewiswyd fel rhan o gystadleuaeth gyhoeddus yn 2018. Bydd tîm New Horizons yn cyflwyno enw priodol i'r Undeb Seryddol Rhyngwladol wedi'r llong ofod hedfan heibio'r gwrthrych yn Ionawr 2019, pan fydd y natur y gwrthrych yn fwy hysbys. Dyma'r gwrthrych pellaf yng Nghysawd yr haul sydd wedi ei ymweld gan long ofod.
== Cyfeiriadau ==
{{cyfeiriadau}}
'''Notelist'''
<references group="lower-alpha" responsive=""></references>
<references group="">
<ref name="Ultima Thule"><cite class="citation web">[https://www.nasa.gov/feature/new-horizons-chooses-nickname-for-ultimate-flyby-target "New Horizons Chooses Nickname for 'Ultimate' Flyby Target"]. NASA. 13 March 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">13 March</span> 2018</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="jpldata"><cite class="citation web">[http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2486958 "JPL Small-Body Database Browser: 486958 (2014 MU69)"] (2014-10-22 last obs.). [[Jet Propulsion Laboratory]]<span class="reference-accessdate">. Retrieved <span class="nowrap">15 March</span> 2017</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="MPC-486958"><cite class="citation web">[http://www.minorplanetcenter.net/db_search/show_object?object_id=486958 "486958 (2014 MU69)"]. ''Minor Planet Center''<span class="reference-accessdate">. Retrieved <span class="nowrap">15 March</span> 2017</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="MPC-Circulars-Archive"><cite class="citation web">[http://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html "MPC/MPO/MPS Archive"]. ''Minor Planet Center''<span class="reference-accessdate">. Retrieved <span class="nowrap">24 November</span> 2017</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="Buie"><cite class="citation web">[[Marc W. Buie|Buie, Marc]] (15 October 2014). [http://www.stsci.edu/institute/stuc/oct-2014/New-Horizons.pdf "New Horizons HST KBO Search Results: Status Report"] <span class="cs1-format">(PDF)</span>. [[Space Telescope Science Institute]]. p. 23.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="Lakdawalla2014"><cite class="citation web">[[Emily Lakdawalla|Lakdawalla, Emily]] (15 October 2014). [http://www.planetary.org/blogs/emily-lakdawalla/2014/10151024-finally-new-horizons-has-a-kbo.html "Finally! New Horizons has a second target"]. ''Planetary Society blog''. [[Planetary Society]]. [https://web.archive.org/web/20141015230432/http://www.planetary.org/blogs/emily-lakdawalla/2014/10151024-finally-new-horizons-has-a-kbo.html Archived] from the original on 15 October 2014.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="NH-2017"><cite class="citation web">[[Alan Stern]] (8 August 2017). [http://pluto.jhuapl.edu/News-Center/PI-Perspectives.php?page=piPerspective_08_08_2017 "The PI's Perspective: The Heroes of the DSN and the 'Summer of MU69<span class="cs1-kern-right">'</span>"]. New Horizons – NASA<span class="reference-accessdate">. Retrieved <span class="nowrap">8 August</span> 2017</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="NYT-2017"><cite class="citation news">Chang, Kenneth (8 August 2017). [https://www.nytimes.com/2017/08/08/science/new-horizons-nasa-pluto-mu69-occultations.html "Chasing Shadows for a Glimpse of a Tiny World Beyond Pluto"]. ''[[The New York Times]]''<span class="reference-accessdate">. Retrieved <span class="nowrap">9 August</span> 2017</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="NASA-new-target-2015"><cite class="citation web">Talbert, Tricia (28 August 2015). [http://www.nasa.gov/feature/nasa-s-new-horizons-team-selects-potential-kuiper-belt-flyby-target "NASA's New Horizons Team Selects Potential Kuiper Belt Flyby Target"]. ''[[NASA]]''<span class="reference-accessdate">. Retrieved <span class="nowrap">4 September</span> 2015</span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="Lakdawalla2015"><cite class="citation web">[[Emily Lakdawalla|Lakdawalla, Emily]] (1 September 2015). [http://www.planetary.org/blogs/emily-lakdawalla/2015/09011608-new-horizons-extended-mission-pt1.html "New Horizons extended mission target selected"]. ''Planetary Society blog''. [[Planetary Society]].</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
<ref name="Buie-DES"><cite class="citation web">[[Marc W. Buie]]. [http://www.boulder.swri.edu/~buie/kbo/astrom/486958.html "Orbit Fit and Astrometric record for 486958"]. SwRI (Space Science Department)<span class="reference-accessdate">. Retrieved <span class="nowrap">2018-02-18</span></span>.</cite><templatestyles src="Module:Citation/CS1/styles.css"></templatestyles></ref>
</references>
[[Categori:Pages with unreviewed translations]]
| 