Science

Judi Lynn

(160,530 posts) Thu Jul 2, 2015, 02:59 PM Jul 2015

Hubble telescope spots Pluto’s moons wobbling in ‘chaos’

Hubble telescope spots Pluto’s moons wobbling in ‘chaos’

 Jun 3, 2015

NASA has released a series of images created based on data from the Hubble Space Telescope, and upon first glance they appear to show dinosaur egg-like oblong objects — those objects are, however, Pluto’s moons Hydra and Nix, and according to the space agency they are “tumbling in absolute chaos”. Such a conclusion was made after analyzing the data from Hubble, which reveals that the two moons wobble about rather than have any set steady course. You can see the "chaos" for yourself in a series of illustrations NASA has released.

The illustrations are shown below, and are computer models based on the Hubble data created to show how the moon Nix in particular has a drastically changing orientation. Says NASA, the sunrise would never be predictable if you happened to live on one of these moons. Both moons, it seems, suffer from this chaotic wobble.

The moons aren’t to blame for this issue, though. Says the space agency, the gravitational fields in which they’re embedded are constantly shifting and the moons are at their mercy. The shifts themselves are caused by the double planet arrangement that Pluto and Charon have, with the common center of gravity shared between them ultimately being the cause.

It doesn't help that the moons are oblong-shaped, giving them a sort of football-like construction that further amplifies the wobbly effects. A pair of Pluto’s other moons, Styx and Kerberos, are also thought to be suffering from this tumbling motion. The researchers who made the discovery plan to detail it in a full report in Nature tomorrow.

More:
http://www.slashgear.com/hubble-telescope-spots-plutos-moons-wobbling-in-chaos-03386650/

8 replies

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Highlight:

Hubble telescope spots Pluto’s moons wobbling in ‘chaos’ (Original Post) Judi Lynn Jul 2015 OP

They look like Idaho's finest baking potatoes to me Warpy Jul 2015 #1

No, I don't think there's any inward spiraling involved muriel_volestrangler Jul 2015 #4

They've only recently been discovered Warpy Jul 2015 #5

But NASA thinks the moons have been there billions of years muriel_volestrangler Jul 2015 #6

Not enough observational data to arrive at that conclusion Warpy Jul 2015 #7

They have computer models muriel_volestrangler Jul 2015 #8

will we see a rivalry between New Horizons and Hubble now? MisterP Jul 2015 #2

THey do! :D roguevalley Jul 2015 #3

Warpy

(111,261 posts)

1. They look like Idaho's finest baking potatoes to me

Reply to Judi Lynn (Original post)

Thu Jul 2, 2015, 03:09 PM

Jul 2015

The motion probably indicates they don't have stable orbits but are spiraling in toward either Pluto or Charon, depending on which one is in the way first.

muriel_volestrangler

(101,316 posts)

4. No, I don't think there's any inward spiraling involved

Reply to Warpy (Reply #1)

Fri Jul 3, 2015, 05:47 PM

Jul 2015

This is about the orientation of the moons, not their orbits. The abstract:

Four small moons—Styx, Nix, Kerberos and Hydra—follow near-circular, near-equatorial orbits around the central ‘binary planet’ comprising Pluto and its large moon, Charon. New observational details of the system have emerged following the discoveries of Kerberos and Styx. Here we report that Styx, Nix and Hydra are tied together by a three-body resonance, which is reminiscent of the Laplace resonance linking Jupiter’s moons Io, Europa and Ganymede. Perturbations by the other bodies, however, inject chaos into this otherwise stable configuration. Nix and Hydra have bright surfaces similar to that of Charon. Kerberos may be much darker, raising questions about how a heterogeneous satellite system might have formed. Nix and Hydra rotate chaotically, driven by the large torques of the Pluto–Charon binary.

http://www.nature.com/nature/journal/v522/n7554/full/nature14469.html

Warpy

(111,261 posts)

5. They've only recently been discovered

Reply to muriel_volestrangler (Reply #4)

Fri Jul 3, 2015, 05:57 PM

Jul 2015

and it would likely take a century or more of close observation to determine the stability of their orbits.

muriel_volestrangler

(101,316 posts)

6. But NASA thinks the moons have been there billions of years

Reply to Warpy (Reply #5)

Fri Jul 3, 2015, 06:23 PM

Jul 2015

Their press release on this:

Pluto's moons are believed to have been formed by a collision between the dwarf planet and a similar-sized body early in the history of our solar system. The smashup flung material that consolidated into the family of moons observed around Pluto today. Its binary companion, Charon, is almost half the size of Pluto and was discovered in 1978. Hubble discovered Nix and Hydra in 2005, Kerberos in 2011, and Styx in 2012. These little moons, measuring just tens of miles in diameter, were found during a Hubble search for objects that could be hazards to the New Horizons spacecraft as it passes the dwarf planet in July.

http://www.nasa.gov/press-release/nasa-s-hubble-finds-pluto-s-moons-tumbling-in-absolute-chaos