Transits between planets as seen from Earth’s surface are rare events. Those between Jupiter and Saturn are even rarer. The next one will take place on 7541 CE, February 16 and again four months later on Jun 17! . The real problem is to establish from where these event will be visible. The local circumstances depend on the variation of the rotation speed of the Earth and more precisely on the delta T value estimated for that time. How reliable is the parabolic function commonly used to predict the delta T value in 7541 CE? Nobody knows, so I assume the first one visible from Sydney, Australia and the second one from Calcutta, India. The VSOP87 theory cannot predict these phenomena, too far from the temporal limits of the ephemeris. But the JPL DE431, as expected, succeeds perfectly. Those lines that appear inside the planetary disks represent the PABL, the Position Angle of the Bright Limb, which I will use for the representation of the phase of the planets. The first event will be a partial occultation, but during the second event the Saturn’s disk will be completely hidden behind Jupiter.
