[X] My Assistant

[ngunn]

I hope the following very non-specialist post will interest some readers - and maybe even winkle out an expert reply or two.

Cassini is about to pull off a special trick. The next two Titan flybys are only 8 days apart. That single fact alone tells a great deal about what Cassini is up to. For Titan, 8 days is just half a month, meaning that the encounters happen on opposite sides of Titan’s orbit. Now it’s not that special for the orbits of two bodies to meet at two widely distant points. But for the two bodies to take exactly the same time to get from one point to the other is very special: it implies that their orbits must be twins. They must not only be the same size but the same shape too, in this case a fair approximation to a circle. The only way in which the orbits may (and do) differ greatly is in inclination. The double act will not last long, however, as Cassini’s orbit continues to be reshaped to meet it’s destined targets.

Over the coming weeks I hope this unusual event, and its implications for Cassini and the geometry of future Titan encounters, will be remarked upon at greater length by the Cassini team, or maybe by others here and elsewhere.

Watch out for the mission descriptions appearing on the Cassini website. Will we get a double-header for both flybys, as we did with Enceladus last year?