europa-orb-all.xml
8.63 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
<?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://amda.irap.omp.eu/public/schemas/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/CNES/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>