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This bar indicates that you are within the PDS enterprise which includes 6 science discipline nodes and 2 support nodes which are overseen by the Project Management Office at NASA's Goddard Space Flight Center (GSFC). Each node is led by an expert in the subject discipline, supported by an advisory group of other practitioners of that discipline, and subject to selection and approval under a regular NASA Research Announcement.

Longitude Systems and Conversion

P1 = reference rotational period of system #1
P2 = reference rotational period of system #2
L1(t-t0) is a known system #1 longitude relative to time t0
L2(t-t0) is the desired longitude value in system #2 relative to time t0
L2(t-t0) = L1(t-t0) + L21 + (t-t0) · [ (24 · 360/P2) - (24 · 360/P1) ]
L21 is a reference longitude. It is defined as:
L21= L2(t=t0) - L1(t=t0)

Jupiter

SI = 9h 50m 30.003s = 877.90°/24h. Used for equatorial motions.
SII = 9h 55m 40.632s = 870.27°/24h. Used for mid-latitudes and GRS.
SIII = 9h 55m 29.711s ± 0.04s = 9.9249197h ± 0.000011h = 870.536°/24h ± 0.000966°/24h
lambdaI = 67.10 + 877.900 · (t-t0)
lambdaII = 43.30 + 870.270 · (t-t0)
lambdaIII = 284.95 + 870.536 · (t-t0)
lambda(SIII) = lambda(SI) + 217.85 - 7.364 · (t-t0)
lambda(SIII) = lambda(SII) + 241.65 + 0.266 · (t-t0)
where t0 = 2451545.0 TDB or Jan. 1.5, 2000.
UIII(SI) = 106.35 m/s
UIII(SII) = -3.4 m/s



Saturn

SIII = 10h 39m 22.4s ± 7s = 10.656222h ± 0.00194h = 810.7939024°/24h ± 0.148°/24h

lambdaIII = 38.90 + 810.793902 · (t-t0)
lambdaI = 227.2037 + 844.3 · (t-t0)
lambda(SIII) = lambda(SI) + 171.6963 - 33.5061 · (t-t0)
UIII(SI) = 410.36 m/s

For the Voyager encounters the reference time should be set to the closest approach time. Other possibilities are:

P1P2FDS(t=0)L21
Neptune17.86616.1111200.0-334.5365