Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
Pluto
(section)
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
{{Short description|Dwarf planet}} {{About|the dwarf planet|the deity|Pluto (mythology)|other uses|Pluto (disambiguation)}} {{Featured article}} {{Pp-semi-indef}} {{Pp-move}} {{Use American English|date=August 2024}} {{Use mdy dates|date=August 2024}} {{Infobox planet | name = Pluto | minorplanet = yes | symbol = [[File:Pluto monogram (bold).svg|24px|♇|class=skin-invert]] or [[File:Pluto symbol (large orb, bold).svg|24px|⯓|class=skin-invert]]<!--Do not delete the bident symbol; it is not merely astrological. NASA has used it; moreover, the IAU specifically discourages use of symbols--> | image = Pluto in True Color - High-Res.jpg | caption = Pluto in true color as imaged by the ''[[New Horizons]]'' spacecraft in July 2015.{{efn|name = caption|This photograph was taken by the [[Ralph (New Horizons)|Ralph]] imager aboard New Horizons on July 14, 2015, from a distance of {{convert|35,445|km|mi|abbr=on}}}} | background = PapayaWhip | discoverer = [[Clyde W. Tombaugh]] | discovered = February 18, 1930 | discovery_site = [[Lowell Observatory]] | mpc_name = (134340) Pluto | named_after = [[Pluto (mythology)|Pluto]] | mp_category = {{Plain list| * [[Dwarf planet]] * [[Trans-Neptunian object]] * [[Kuiper belt]] object * [[Plutino]] }} | orbit_ref = <ref name="TOP2013" />{{efn|name = MeanElements|The mean elements here are from the Theory of the Outer Planets (TOP2013) solution by the Institut de mécanique céleste et de calcul des éphémérides (IMCCE). They refer to the standard equinox J2000, the barycenter of the Solar System, and the epoch J2000.}} | epoch = [[J2000]] | earliest_precovery_date = August 20, 1909 | aphelion = {{Plain list| * {{val|49.305|ul=AU}} * ({{nowrap|{{val|fmt=commas|7.37593|u=billion km}}}}) * February 2114 }} | perihelion = {{Plain list| * {{val|29.658|u=AU}} * ({{nowrap|{{val|fmt=commas|4.43682|u=billion km}}}})<ref name="Pluto Fact Sheet" /> * (September 5, 1989)<ref name="jpl-ssd-horizons" /> }} | semimajor = {{Plain list| * {{val|39.482|u=AU}} * ({{nowrap|{{val|fmt=commas|5.90638|u=billion km}}}}) }} | eccentricity = {{val|0.2488}} | inclination = {{Plain list| * {{val|17.16|u=°}} * (11.88° to Sun's equator) }} | asc_node = {{val|110.299|u=°}} | arg_peri = {{val|113.834|u=°}} | period = {{Plain list| * {{val|247.94}} [[julian year (astronomy)|years]]<ref name="Pluto Fact Sheet" /> * {{nowrap|{{val|fmt=commas|90560|u=days}}}}<ref name="Pluto Fact Sheet" /> <!-- * {{nowrap|{{val|fmt=commas|14164.4}}}} Plutonian [[solar day]]s<ref name="planet_years" /> --> }} | synodic_period = 366.73 days<ref name="Pluto Fact Sheet" /> | avg_speed = 4.743 km/s<ref name="Pluto Fact Sheet" /> | mean_anomaly = {{val|14.53|u=[[Degree (angle)|deg]]}} | satellites = [[Moons of Pluto|5]] | mean_radius = {{Plain list| * {{nowrap|{{val|fmt=commas|1188.3|0.8|u=km}}}}<ref name = "Pluto System after New Horizons">{{cite journal |last1=Stern |first1=S.A. |last2=Grundy |first2=W. |last3=McKinnon |first3=W.B. |last4=Weaver |first4=H.A. |last5=Young |first5=L.A. |title=The Pluto System After New Horizons |journal=Annual Review of Astronomy and Astrophysics |volume=2018 |pages=357–392 |arxiv=1712.05669 |year=2017 |bibcode=2018ARA&A..56..357S |s2cid=119072504 |doi=10.1146/annurev-astro-081817-051935|issn = 0066-4146}}</ref><ref name="Nimmo2017">{{cite journal |last=Nimmo |first=Francis |display-authors=etal |title=Mean radius and shape of Pluto and Charon from New Horizons images |journal=Icarus |date=2017 |volume=287 |pages=12–29 |bibcode=2017Icar..287...12N |arxiv=1603.00821 |s2cid=44935431 |doi=10.1016/j.icarus.2016.06.027}}</ref> * 0.1868 [[Earth radius|Earths]]}} | dimensions = {{val|fmt=commas|2376.6|1.6|u=km}} (observations consistent with a sphere, predicted deviations too small to be observed)<ref name="Nimmo2017"/> | surface_area = {{Plain list| * {{val|1.774443|e=7|u=km2}}{{efn|name=Surface area}} * 0.035 Earths }} | volume = {{Plain list| * {{val|7.057|0.004|e=9|u=km3}}{{efn|name=Volume}} * {{val|0.00651|u=Earths}} }} | mass = {{Plain list| * {{val|1.3025|0.0006|e = 22|u=kg}}<ref name="Brozovic2024"/><!-- Calculated from GM=869.3 ± 0.4 km3 s–2 --> * {{val|0.00218|u=[[Earth mass|Earths]]|fmt=none}} * 0.177 [[Moon mass|Moons]] }} | density = {{val|1.853|0.004|u=g/cm3}}<ref name="Brozovic2024"/> | surface_grav = {{cvt|0.620|m/s2|g0|lk=out}}{{efn|name = Surface gravity}} | escape_velocity = {{val|1.212}} km/s{{efn|name = Escape velocity}} | rotation = {{Plain list| * {{val|−6.38680|u=day}} * −6 d, 9 h, 17 m, 00 s }}<ref name="planet_years">{{cite web |url=http://cseligman.com/text/sky/rotationvsday.htm |title=Rotation Period and Day Length |last=Seligman |first=Courtney |access-date=June 12, 2021 |archive-date=September 29, 2018 |archive-url=https://web.archive.org/web/20180929010908/http://cseligman.com/text/sky/rotationvsday.htm |url-status=live }}</ref> | sidereal_day = {{Plain list| * {{val|−6.387230|u=day}} * −6 d, 9 h, 17 m, 36 s }} | rot_velocity = {{cvt|47.18|km/h|m/s|disp=out}}{{citation needed|date=July 2024}} | axial_tilt = {{val|119.51|u=°}} (to orbit)<ref name="Pluto Fact Sheet" /> | right_asc_north_pole = 132.993°<ref name="Archinal" /> | declination = −6.163°<ref name="Archinal" /> | albedo = 0.52 [[Geometric albedo|geometric]] (locally 0.08–1.0)<ref name="Pluto Fact Sheet" /><br />0.72 ± 0.07 [[Bond albedo|Bond]]<ref name="Pluto Fact Sheet" /> | magnitude = 13.65<ref name="Pluto Fact Sheet" /> to 16.3<ref name="AstDys-Pluto" /> <br /> (mean is 15.1)<ref name="Pluto Fact Sheet" /> | abs_magnitude = −0.44<ref name="jpldata" /> | angular_size = 0.06{{pprime}} to 0.11{{pprime}}<ref name="Pluto Fact Sheet" />{{efn|name = Angular size}} | pronounced = {{IPAc-en|audio=en-us-Pluto.ogg|ˈ|p|l|uː|t|oʊ}} | adjectives = [[Wiktionary:Plutonian#Adjective 2|Plutonian]] {{IPAc-en|p|l|uː|ˈ|t|oʊ|n|i|ə|n}}<ref>{{Cite OED|Plutonian}}</ref> | atmosphere = yes | temp_name1 = [[Kelvin]] | min_temp_1 = 33 K | mean_temp_1 = 44 K (−229 °C) | max_temp_1 = 55 K | surface_pressure = 1.0 [[pascal (unit)|Pa]] (2015)<ref name=Stern2015 /><ref>{{cite news |last=Amos |first=Jonathan |url=https://www.bbc.com/news/science-environment-33657447 |title=New Horizons: Pluto may have 'nitrogen glaciers' |publisher=BBC News |date=July 23, 2015 |access-date=July 26, 2015 |quote=It could tell from the passage of sunlight and radiowaves through the Plutonian "air" that the pressure was only about 10 microbars at the surface |archive-date=October 27, 2017 |archive-url=https://web.archive.org/web/20171027182142/http://www.bbc.com/news/science-environment-33657447 |url-status=live }}</ref> ({{val|9.9|e=-6|u=[[atmosphere (unit)|atm]]}}) | atmosphere_composition = [[Nitrogen]], [[methane]], [[carbon monoxide]]<ref name="Physorg April 19, 2011" /> | note = no | scale_height = | flattening = <1%<ref name="Stern2015" /> }} <!-- Per [[WP:LEADCITE]], there is no need to cite material in the lead if it is cited elsewhere. --> '''Pluto''' ([[minor-planet designation]]: '''134340 Pluto''') is a [[dwarf planet]] in the [[Kuiper belt]], a ring of [[Trans-Neptunian object|bodies beyond the orbit of Neptune]]. It is the ninth-largest and tenth-most-massive known object to directly orbit the [[Sun]]. It is the largest known [[trans-Neptunian object]] by volume by a small margin, but is less massive than [[Eris (dwarf planet)|Eris]]. Like other Kuiper belt objects, Pluto is made primarily of ice and rock and is much smaller than the [[inner planet]]s. Pluto has roughly one-sixth the mass of the [[Moon]] and one-third its volume. Originally considered a planet, its classification was changed when astronomers adopted a new [[definition of planet|definition of ''planet'']]. Pluto has a moderately [[Orbital eccentricity|eccentric]] and [[Inclination|inclined]] orbit, ranging from {{convert|30|to|49|AU|e9km e9mi|lk=on|abbr=off}} from the Sun. Light from the Sun takes 5.5 hours to reach Pluto at its orbital distance of {{convert|39.5|AU|e9km e9mi|abbr=unit|}}. Pluto's eccentric orbit periodically brings it closer to the Sun than [[Neptune]], but a stable [[orbital resonance]] prevents them from colliding. Pluto has [[moons of Pluto|five known moons]]: [[Charon (moon)|Charon]], the largest, whose diameter is just over half that of Pluto; [[Styx (moon)|Styx]]; [[Nix (moon)|Nix]]; [[Kerberos (moon)|Kerberos]]; and [[Hydra (moon)|Hydra]]. Pluto and Charon are sometimes considered a [[binary system]] because the [[barycenter]] of their orbits does not lie within either body, and they are [[tidally locked]]. ''[[New Horizons]]'' was the first spacecraft to visit Pluto and its moons, making a [[Planetary flyby|flyby]] on July 14, 2015, and taking detailed measurements and observations. Pluto was discovered in 1930 by [[Clyde W. Tombaugh]], making it the first known object in the Kuiper belt. It was immediately hailed as the [[ninth planet]]. However,<ref name=T&M/>{{rp|27}} its planetary status was questioned when it was found to be much smaller than expected. These doubts increased following the discovery of additional objects in the Kuiper belt starting in the 1990s, particularly the more massive [[scattered disk]] object [[Eris (dwarf planet)|Eris]] in 2005. In 2006, the [[International Astronomical Union]] (IAU) formally redefined the term ''planet'' to exclude dwarf planets such as Pluto. Many planetary astronomers, however, continue to consider Pluto and other dwarf planets to be planets.
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)