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Pluto's Outer Moons Orbit Chaotically, With Unpredictable Sunrises and Sunsets

Posted by samzenpus on from the trying-to-get-some-sleep dept.

StartsWithABang writes: Few things in this world are as regular as sunrise and sunset. With the application of a little physics, you can predict exactly where and when the sun will rise or set from any location on Earth. Thus far, every world in our Solar System — planet, moon and asteroid — has had the exact same experience as us. But out in the Kuiper belt, Pluto is different. The only known world in the Solar System where a significant fraction of the system's mass is not in a single component, the outer moons of the Pluto-Charon system provide a unique environment to study how planets might behave in orbit around binary stars. The amazing takeaway? The rotational part of the orbit is chaotic; the worlds tumble, and hence sunrises and sunsets are no longer predictable.

2 of 92 comments (clear)

  1. Re:Do they really mean "chaotic"? by Anonymous Coward · · Score: 3, Interesting

    I can't say anything about the math, but the video does look as if there is a phase change into chaotic behavior, i.e. the satellite "tumbles out of control". Here Nix's oblong shape helps turning it into a "wobbly duck". IIRC chaos means that a tiny change in initial conditions at time T can cause an arbitrarily big change at time T + delta T, thus making the result unpredictable (in spite of there being an exact formula for it) because there is always a measuring error.

  2. Not the only chaotically rotating moon by mr.gson · · Score: 3, Interesting

    Saturn's moon Hyperion is also known to tumble chaotically.