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

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.

Comments

Add one to your bounce rate

[Anonymous Coward]

Click link
Medium.com
Click back

At this point you could be posting next weeks lotto numbers, I still wouldn't read it.

Re:Add one to your bounce rate

[jandersen]

Yeah - and I thought that the "Turn off adverts" option would block medium.com SPAM.

Do they really mean "chaotic"?

[wonkey_monkey]

The rotational part of the orbit is chaotic; the worlds tumble, and hence sunrises and sunsets are no longer predictable.

"Rotating around more than one axis" doesn't automatically mean chaotic, does it?

Also there was this quote from the article:

If you were on a fixed point on the surface of Nix, you’d see the Sun rise in the east on one day, then at an ever-changing angle over the next few days, and eventually it would rise in the west, cycling through in chaotic fashion.

Aren't "cycling" and "chaotic" mutually exclusive?

Even on Earth the Sun rises in an "ever-changing position" at an "ever-changing angle," but we don't call that chaotic.

Re:Do they really mean "chaotic"?

[wonkey_monkey]

Or to put it another way, do they mean it really isn't predictable (perhaps because of all the gravitational influences in the area), or that the math is just a bit harder?

Re:Do they really mean "chaotic"?

[jandersen]

A tip that can save you a good deal of wasted effort: if the link is to medium.com, they probably havn't got all that much of a clue. Medium.com is a glossy magazine on par with "Heat", "Hello" and the like; I can't imagine anybody with technical or scientific insight wanting to waste time on it.

Re:Do they really mean "chaotic"?

[srussia]

Yes. It's an n-body dynamical system.

Re:Do they really mean "chaotic"?

[Anonymous Coward]

They mean it's chaotic in that a small change in initial conditions throw your predictions completely off. It's "a bit harder" like the Mandelbrot set is "a bit more complicated than" a circle.

Re:Do they really mean "chaotic"?

[Anonymous Coward]

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.

Re:Do they really mean "chaotic"?

[Noah Haders]

in westeros the cycles of summer and winter are chaotically unpredictable.

Re:Do they really mean "chaotic"?

[kanweg]

"the sun is just a star in the sky that's a bit brighter than the others"
A bit very much brighter star than the others, actually:

http://blogs.discovermagazine....

It is far more bright than the full moon.

Bert

Incredible

[cachimaster]

Not a single science fiction writer, or scientific study that I know, imagined worlds with chaotic orbits. But here is one, in our own solar system. And we found out just now.

Re:Incredible

[Lumpy]

medium.com's definition of chaotic is getting the wrong coffee from the barista.

Re:Incredible

[cellocgw]

Not a single science fiction writer, or scientific study that I know, imagined worlds with chaotic orbits

Cixin Liu, "The Three-body Problem."
There are several old-ish scifi stories but I don't recall their titles at this instant.

Non planet with moons

[Crashmarik]

Definition Moon: any planetary satellite:
the moons of Jupiter.

Re:Non planet with moons

[Crashmarik]

Definition of moon is any natural celestial body orbiting another that is not a star. Asteroids have had known moons before the whole planet definition mess, and the definition of moon has never been restricted to going around a planet, under old or new definition.

Well aside from the fact that would define Pluto and Charon as each others moon. or none of these as moons, your knowledge seems to argue against

Merriam Webster,

the moon : the large round object that circles the Earth and that shines at night by reflecting light from the sun

: a large round object like the moon that circles around a planet other than the Earth
22 charming words for nasty people
Full Definition of MOON
1
a often capitalized : the earth's natural satellite that shines by the sun's reflected light, revolves about the earth from west to east in about 2912 days with reference to the sun or about 2713 days with reference to the stars, and has a diameter of 2160 miles (3475 kilometers), a mean distance from the earth of about 238,900 miles (384,400 kilometers), and a mass about one eightieth that of the earth —usually used with the
b : one complete moon cycle consisting of four phases
c : satellite 2; specifically : a natural satellite of a planet

and universe today

A moon is defined to be a celestial body that makes an orbit around a planet, including the eight major planets, dwarf planets, and minor planets. A moon may also be referred to as a natural satellite, although to differentiate it from other astronomical bodies orbiting another body, e.g. a planet orbiting a star, the term moon is used exclusively to make a reference to a planet’s natural satellite.

Now I hardly hold the bad usage against you, This is merely part of the problem of the badly done rush to redefine what is a planet.

Eh.

[fuzzyfuzzyfungus]

Asteroids do not concern me, Slashdot.

Re:That's no moons

[michelcolman]

Dwarf moons?

Not the only chaotically rotating moon

[mr.gson]

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

Re:I doubt they are chaotic

[PlusFiveTroll]

http://www.dynamics.unam.edu/B...

Evolution of attractors in quasiperiodically forced systems, From quasiperiodic to strange nonchaotic to chaotic.