europa-orb-all.xml
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<?xml version="1.0" encoding="UTF-8"?>
<Spase xmlns="http://www.spase-group.org/data/schema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.spase-group.org/data/schema http://www.spase-group.org/data/schema/spase-2_3_1.xsd">
<Version>2.3.1</Version>
<NumericalData>
<ResourceID>spase://CNES/NumericalData/CDPP-AMDA/Ephemerides/europa-orb-all</ResourceID>
<ResourceHeader>
<ResourceName>Europa</ResourceName>
<ReleaseDate>2018-10-14T11:46:29Z</ReleaseDate>
<Description>Europa orbits Jupiter in just over three and a half days,
with an orbital radius of about 670,900 km. With an eccentricity of only
0.009, the orbit itself is nearly circular, and the orbital inclination
relative to Jupiter's equatorial plane is small, at 0.470°.
Like its fellow Galilean satellites, Europa is tidally locked to Jupiter,
with one hemisphere of Europa constantly facing Jupiter. Because of this,
there is a sub-Jovian point on Europa's surface, from which Jupiter would
appear to hang directly overhead. Europa's prime meridian is the line
intersecting this point. Research suggests that the tidal locking may not be
full, as a non-synchronous rotation has been proposed: Europa spins faster
than it orbits, or at least did so in the past.
This suggests an asymmetry in internal mass distribution and that a layer of
subsurface liquid separates the icy crust from the rocky interior.
The slight eccentricity of Europa's orbit, maintained by the gravitational disturbances from
the other Galileans, causes Europa's sub-Jovian point to oscillate around a mean position.
As Europa comes slightly nearer to Jupiter, Jupiter's gravitational attraction increases,
causing Europa to elongate towards and away from it. As Europa moves slightly away from
Jupiter, Jupiter's gravitational force decreases, causing Europa to relax back into a more
spherical shape, and creating tides in its ocean. The orbital eccentricity of Europa is
continuously pumped by its mean-motion resonance with Io.
Thus, the tidal flexing kneads Europa's interior and gives it a source of heat, possibly
allowing its ocean to stay liquid while driving subsurface geological processes.
The ultimate source of this energy is Jupiter's rotation, which is tapped by Io
through the tides it raises on Jupiter and is transferred to Europa and Ganymede by the
orbital resonance.</Description>
<Contact>
<PersonID>spase://CNES/Person/NAIF</PersonID>
<Role>PrincipalInvestigator</Role>
</Contact>
<Association>
<AssociationID>jup-moons-orb</AssociationID>
<AssociationType>PartOf</AssociationType>
<Note>Jupiter Moons</Note>
</Association>
</ResourceHeader>
<AccessInformation>
<RepositoryID>spase://SMWG/Repository/CDPP/AMDA</RepositoryID>
<Availability>Online</Availability>
<AccessRights>Open</AccessRights>
<AccessURL>
<URL>http://amda.cdpp.eu</URL>
</AccessURL>
<Format>Text.ASCII</Format>
</AccessInformation>
<ProviderName>SPICE</ProviderName>
<InstrumentID>spase://CNES/Instrument/CDPP-AMDA/Ephemerides</InstrumentID>
<MeasurementType>Ephemeris</MeasurementType>
<TemporalDescription>
<TimeSpan>
<StartDate>1970-01-01T00:00:05Z</StartDate>
<StopDate>2036-12-31T23:40:04Z</StopDate>
</TimeSpan>
<Cadence>PT20M</Cadence>
</TemporalDescription>
<ObservedRegion>Jupiter</ObservedRegion>
<ObservedRegion>Jupiter.Europa</ObservedRegion>
<Parameter>
<Name>distance europa-jupiter</Name>
<ParameterKey>eur_jup_r</ParameterKey>
<Ucd/>
<Units>Rj</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<Support>
<SupportQuantity>Positional</SupportQuantity>
</Support>
</Parameter>
<Parameter>
<Name>xyz_jsm</Name>
<ParameterKey>eur_jup_jsm</ParameterKey>
<Ucd/>
<Units>Rj</Units>
<CoordinateSystem>
<CoordinateRepresentation>Cartesian</CoordinateRepresentation>
<CoordinateSystemName>JSM</CoordinateSystemName>
</CoordinateSystem>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<Structure>
<Size>3</Size>
<Element>
<Name>x</Name>
<Index>1</Index>
<ParameterKey>eur_jup_jsm(0)</ParameterKey>
</Element>
<Element>
<Name>y</Name>
<Index>2</Index>
<ParameterKey>eur_jup_jsm(1)</ParameterKey>
</Element>
<Element>
<Name>z</Name>
<Index>3</Index>
<ParameterKey>eur_jup_jsm(2)</ParameterKey>
</Element>
</Structure>
<Support>
<SupportQuantity>Positional</SupportQuantity>
</Support>
</Parameter>
<Parameter>
<Name>xyz_jso</Name>
<ParameterKey>eur_jup_jso</ParameterKey>
<Ucd/>
<Units>Rj</Units>
<CoordinateSystem>
<CoordinateRepresentation>Cartesian</CoordinateRepresentation>
<CoordinateSystemName>JSO</CoordinateSystemName>
</CoordinateSystem>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<Structure>
<Size>3</Size>
<Element>
<Name>x</Name>
<Index>1</Index>
<ParameterKey>eur_sat_jso(0)</ParameterKey>
</Element>
<Element>
<Name>y</Name>
<Index>2</Index>
<ParameterKey>eur_jup_jso(1)</ParameterKey>
</Element>
<Element>
<Name>z</Name>
<Index>3</Index>
<ParameterKey>eur_jup_jso(2)</ParameterKey>
</Element>
</Structure>
<Support>
<SupportQuantity>Positional</SupportQuantity>
</Support>
</Parameter>
<Parameter>
<Name>xyz_IAU_jupiter</Name>
<ParameterKey>eur_jup_xyz</ParameterKey>
<Ucd/>
<Units>Rj</Units>
<CoordinateSystem>
<CoordinateRepresentation>Cartesian</CoordinateRepresentation>
<CoordinateSystemName>IAU_Jupiter</CoordinateSystemName>
</CoordinateSystem>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<Structure>
<Size>3</Size>
<Element>
<Name>x</Name>
<Index>1</Index>
<ParameterKey>eur_jup_xyz(0)</ParameterKey>
</Element>
<Element>
<Name>y</Name>
<Index>2</Index>
<ParameterKey>eur_jup_xyz(1)</ParameterKey>
</Element>
<Element>
<Name>z</Name>
<Index>3</Index>
<ParameterKey>eur_jup_xyz(2)</ParameterKey>
</Element>
</Structure>
<Support>
<SupportQuantity>Positional</SupportQuantity>
</Support>
</Parameter>
<Parameter>
<Name>latitude IAU_jupiter</Name>
<ParameterKey>eur_jup_lat</ParameterKey>
<Ucd/>
<Units>deg</Units>
<Support>
<SupportQuantity>Positional</SupportQuantity>
</Support>
</Parameter>
<Parameter>
<Name>longitude IAU_jupiter</Name>
<ParameterKey>eur_jup_lon</ParameterKey>
<Ucd/>
<Units>deg</Units>
<Support>
<SupportQuantity>Positional</SupportQuantity>
</Support>
</Parameter>
</NumericalData>
</Spase>