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TABLE I |
Recommended values for the direction of the north pole of rotation and the prime meridian of the Sun and planets (2000) |
The standard epoch is 2000 January 1.5, that is, JD 2451545.0 TT |
Sun | α0 = 286°.13 | |
δ0 = 63°.87 | ||
W = 84°.10+14°.1844000d |
Mercury | α0 = 281.01-0.033T | |
δ0 = 61.45-0.005T | ||
W = 329.548+6.1385025d | (a) |
Venus | α0 = 272.76 | |
δ0 = 67.16 | ||
W = 160.20-1.4813688d | (b) |
Earth | α0 = 0.00-0.641T | |
δ0 = 90.00-0.557T | ||
W = 190.147+360.9856235d |
Mars | α0 = 317.68143-0.1061T | |
δ0 = 52.88650-0.0609T | ||
W = 176.630+350.89198226d | (c) |
Jupiter | α0 = 268.05-0.009T | |
δ0 = 64.49+0.003T | ||
W = 284.95+870.5366420d | (d) |
Saturn | α0 = 40.589-0.036T | |
δ0 = 83.537-0.004T | ||
W = 38.90+810.7939024d | (d) |
Uranus | α0 = 257.311 | |
δ0 = -15.175 | ||
W = 203.81-501.1600928d | (d) |
Neptune | α0 = 299.36+0.70 sin N | |
δ0 = 43.46-0.51 cos N | ||
W = 253.18+536.3128492d -0.48 sin N | (d) | |
N = 357.85+52.316T |
Pluto | α0 = 313.02 | |
δ0 = 9.09 | ||
W = 236.77-56.3623195d | (e) |
α0, δ0: Are standard equatorial coordinates with equinox J2000 at epoch J2000. |
Approximate coordinates of the north pole of the invariable plane are α0=273°.85, δ0=66°.99. |
T: Interval in Julian centuries (of 36525 days) from the standard epoch. |
d: Interval in days from the standard epoch. |
(a): The 20° meridian is defined by the crater Hun Kal. |
(b): The 0° meridian is defined by the central peak in the crater Ariadne. |
(c): The 0° meridian is defined by the crater Airy-0. |
(d): The equations for W for Jupiter, Saturn, Uranus and Neptune refer to the rotation of their magnetic fields (System III). On Jupiter, System I (WI= 67°.1 + 877°.900d) refers to the mean atmospheric equatorial rotation; System II (WII= 43°.3 + 870°.270d) refers to the mean atmospheric rotation north of the south component of the north equatorial belt, and south of the north component of the south equatorial belt. |
(e): The 0° meridian is defined as the mean sub-Charon meridian. |