Pallene (moon)

Template:Short description {{#invoke:infobox|infoboxTemplate | class = vcard | titleclass = fn org | title = Pallene | image = {{#invoke:InfoboxImage|InfoboxImage|image=Pallene Cassini color-crop 20101016.png|upright={{#if:||1.1}}|alt=}} | caption = Cassini image of Pallene transiting Saturn on October 16, 2010 | headerstyle = {{#if:|background-color:|background-color:#E0CCFF}} | labelstyle = max-width:{{#if:||11em}}; | autoheaders = y

| header1 = Discovery

| header10 = {{#if:|Designations|Designations}}

| label11 = Template:Longitem | data11 = Saturn XXXIII | label12 = Pronunciation | data12 = Template:IPAc-en<ref>Noah Webster (1884) A Practical Dictionary of the English Language</ref> | label13 = Template:Longitem | data13 = Παλλήνη Pallēnē | label14 = Template:Longitem | data14 = S/1981 S 14 (first discovery)
S/2004 S 2 (second discovery) | label15 = Template:Longitem | data15 = | label16 = Adjectives | data16 = Pallenean Template:IPAc-en<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> | label17 = Symbol | data17 =

| header20 = Orbital characteristics{{#ifeq:|yes| (barycentric)}}Template:Sfn

| data21 = | data22 = {{#if:20 June 2004 (JD 2453177.5) |Epoch 20 June 2004 (JD 2453177.5)}} | data23 = {{#if: | Uncertainty parameter {{{uncertainty}}}}} | label24 = Observation arc | data24 = | label25 = Earliest precovery date | data25 = | label26 = {{#switch:{{{apsis}}} |apsis|gee|barion|center|centre|(apsis)=Apo{{{apsis}}} |Ap{{#if:|{{{apsis}}}|helion}}}} | data26 = | label27 = Peri{{#if:|{{{apsis}}}|helion}} | data27 = | label28 = Peri{{#if:|{{{apsis}}}|apsis}} | data28 = | label29 = {{#switch:{{{apsis}}} |helion|astron=Ap{{{apsis}}} |Apo{{#if:|{{{apsis}}}|apsis}}}} | data29 = | label30 = Periastron | data30 = | label31 = Apoastron | data31 = | label32 = Template:Longitem | data32 = Template:Val<ref name="jpl-satelem"/> | label33 = Template:Longitem | data33 = | label34 = Eccentricity | data34 = Template:Val<ref name="jpl-satelem"/> | label35 = Template:Longitem | data35 = Template:Val<ref name="jpl-satelem"/> | label36 = Template:Longitem | data36 = | label37 = Template:Longitem | data37 = | label38 = Template:Longitem | data38 = | label39 = Template:Longitem | data39 = | label40 = Inclination | data40 = Template:Val (to Saturn's equator) | label41 = Template:Longitem | data41 = | label42 = Template:Longitem | data42 = | label43 = Template:Longitem | data43 = | label44 = Template:Longitem | data44 = | label45 = Template:Longitem | data45 = | label46 = Template:Nowrap | data46 = | label47 = Satellite of | data47 = Saturn | label48 = Group | data48 = Alkyonides | label49 = {{#switch: |yes|true=Satellites |Known satellites}} | data49 = | label50 = Star | data50 = | label51 = Earth MOID | data51 = | label52 = Mercury MOID | data52 = | label53 = Venus MOID | data53 = | label54 = Mars MOID | data54 = | label55 = Jupiter MOID | data55 = | label56 = Saturn MOID | data56 = | label57 = Uranus MOID | data57 = | label58 = Neptune MOID | data58 = | label59 = T_Jupiter | data59 =

| header60 = Proper orbital elements

| label61 = Template:Longitem | data61 = {{#if: |{{{p_semimajor}}} AU}} | label62 = Template:Longitem | data62 = | label63 = Template:Longitem | data63 = | label64 = Template:Longitem | data64 = {{#if: |{{{p_mean_motion}}} deg Template:\yr}} | label65 = Template:Longitem | data65 = {{#if:|{{#expr:360/1 round 5}} yr
({{#expr:365.25*360/1 round 3}} d) }} | label66 = Template:Longitem | data66 = {{#if:|{{{perihelion_rate}}} arcsec Template:\yr }} | label67 = Template:Longitem | data67 = {{#if:|{{{node_rate}}} arcsec Template:\yr}}

| header70 = Template:Anchor{{#if:| Physical characteristics|Physical characteristics}}

| label71 = Dimensions | data71 = Template:Val km
(± Template:Val km)Template:Sfn Template:Rp | label72 = Template:Longitem | data72 = Template:Val Template:Sfn Template:Rp | label73 = Template:Longitem | data73 = | label74 = Template:Longitem | data74 = | label75 = Template:Longitem | data75 = | label76 = Flattening | data76 = | label77 = Circumference | data77 = | label78 = Template:Longitem | data78 = | label79 = Volume | data79 = Template:Val Template:Efn | label80 = Mass | data80 = Template:Val Template:Sfn Template:Rp | label81 = Template:Longitem | data81 = Template:Val Template:Sfn Template:Rp | label82 = Template:Longitem | data82 = Template:Val Template:Sfn Template:Rp | label83 = Template:Longitem | data83 = | label84 = Template:Longitem | data84 = Template:V2 km/s at longest axis
to Template:V2 km/s at poles | label85 = Template:Longitem | data85 = synchronous | label86 = Template:Longitem | data86 = | label87 = Template:Longitem | data87 = | label88 = Template:Longitem | data88 = zero | label89 = Template:Longitem | data89 = | label90 = Template:Longitem | data90 = | label91 = Template:Longitem | data91 = | label92 = Template:Longitem | data92 = | label93 = {{#if: |Template:Longitem |Albedo}} | data93 = | label94 = Temperature | data94 =

| data100 = {{#if:|

Surface temp.	min	mean	max
{{{temp_name1}}}
{{{temp_name2}}}
{{{temp_name3}}}
{{{temp_name4}}}

}}

| header110 = Atmosphere

| below = {{#if:||Template:Reflist }}

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Pallene Template:IPAc-en is a very small natural satellite of Saturn. It is one of three small moons known as the Alkyonides that lie between the orbits of the larger Mimas and Enceladus. It is also designated Template:Nowrap.

DiscoveryEdit

File:S2004s2 040601.jpg

Discovery image of Pallene in 2004 from the Cassini probe

Pallene was discovered by the Cassini Imaging Team in 2004, during the Cassini–Huygens mission.Template:Sfn Template:Sfn It was given the temporary designation Template:Nowrap. In 2005, the name Pallene was provisionally approved by the IAU Division III Working Group for Planetary System Nomenclature,Template:Sfn and was ratified at the IAU General Assembly in 2006. The name refers to Pallene, one of the Alkyonides, the seven beautiful daughters of the giant Alkyoneus.

After the discovery in 2004, it was realized that Pallene had been first photographed on August 23, 1981, by the space probe Template:Nowrap. It had appeared in a single photograph and had been provisionally named Template:Nowrap and estimated to orbit 200,000 km from Saturn.Template:Sfn Because it had not been visible in other images, it had not been possible to compute its orbit at the time, but recent comparisons have shown it to match Pallene's orbit.Template:Sfn

Orbital characteristicsEdit

Pallene is visibly affected by a perturbing mean-longitude resonance with the much larger Enceladus, although this effect is not as large as Mimas's perturbations on Methone. The perturbations cause Pallene's osculating orbital elements to vary with an amplitude of about 4 km in semi-major axis, and 0.02° in longitude (corresponding to about 75 km). Eccentricity also changes on various timescales between 0.002 and 0.006, and inclination between about 0.178° and 0.184°.Template:Sfn

RingEdit

File:Saturn outer rings labeled.svg

Back-illuminated rings of Saturn as seen by Cassini on 15 September 2006. The faint Pallene ring is visible at the bottom left as indicated.

In 2006, images taken in forward-scattered light by the Cassini spacecraft enabled the Cassini Imaging Team to discover a faint dust ring around Saturn that shares Pallene's orbit, now named the Pallene Ring.Template:Sfn Template:Sfn The ring has a radial extent of about 2,500 km. Its source is particles blasted off Pallene's surface by meteoroid impacts, which then form a diffuse ring around its orbital path.Template:Sfn Template:Sfn

ExplorationEdit

File:Pallene N1694657087 cleaned.png

Pallene's crescent illuminated by Saturnshine, imaged by Cassini on 14 September 2011

The Cassini spacecraft, which studied Saturn and its moons until September, 2017, performed a fly-by of Pallene on 16 October 2010, and 14 September 2011 at a distance of 36,000 kilometers (22,000 miles) and 44,000 kilometers respectively.<ref name="smallsatevents">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

NotesEdit

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ReferencesEdit

CitationsEdit

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SourcesEdit

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External linksEdit

Template:Spoken Wikipedia

Template:Moons of Saturn Template:Saturn