Pluto's 3 Moons and a Probe to Study Them

It doesn't come easy writes "For those of you keeping score, Pluto now officially has three moons, with more possibly to follow. The newfound moons orbit about 27,000 miles (44,000 kilometers) from Pluto, more than twice as far as Charon, Pluto's other satellite. They are 5,000 times dimmer than Charon. The moons were found using the Hubble Space Telescope. For now, Pluto is the only Kuiper Belt object known to have satellites. Some nice images of Pluto and its moons are included in links. Enjoy!" Relatedly IZ Reloaded writes "NASA says the Atlas 5 rocket that will carry the New Horizons Pluto probe has suffered slight damage thanks to Hurricane Wilma. New Scientist reports: "The Atlas 5 rocket stands within a construction hangar at Cape Canaveral Air Force Station on Florida's east coast. As Wilma rolled though the region on 24 October, fierce 122-kilometer-per-hour winds tore holes in the hangar's 83-meter-tall door and caused minor damage to the rocket inside.""

Comments

Hubble

[GmAz]

Seems hubble is doing something useful every time you turn around. And NASA says the Hubble Telescope needs to be retired.

Classification

[Da3vid]

Is it really a big deal when we name something a moon? Its just a matter of relativity. A planet, a moon, an asteroid, a rock... they're all the same thing, that varies by degrees. I suppose the things orbital path is of interest, but how much can we really learn just by applying labels? We didn't learn anything about the true scientific nature of those bodies, we just named them. I think I'll name them Susanna, Melinda and Jim.

-Da3vid-

Re:Nice?

[l2718]

A bunch of small white dots is very good, actually. The fact that both Pluto and Charon come out as extended objects in the short exposure picture is quite impressive in its own right. I wonder if the long exposure has better resolution or is smeared due to an imprefect correction for the relative motion of the telescope and Pluto. Any astronomers reading this?

Kinda small...

[Fermatprime]

These "moons" are only 30 and 100 miles across. Mars' Phobos and Deimos, widely thought to be captured asteroids, are thousands of kilometers across. These are PUNY. If we could somehow gather up all the junk orbiting Earth and pack it together, we'd probably have a "moon" about that size, too.

That is why

[jd]

I would be in favour of a classification system that DID mean something. For example, we know that the composition of all the rocky planets we've investigated and all of the Gas Giants is mixed. We also know they have a single core. Neither of these is proven (or disproven) for Pluto, but could be tested. We know that the composition statement is false for all asteroids and the single core is false for all comets. It would seem easy enough to base a classification system on such parameters.

Would this help us any? Probably, yes. Because planets are of mixed composition, they must have formed in the very early accretion disc from the sun. Because asteroids and comets are relatively uniform, they must have formed AFTER centrifugal forces had separated out the elements - lighter elements to the outside (which is why comets contain a lot of hydrogen) and heavier elements towards the center (asteroids are based on iron and nickel, depending on location).

The label, by this scheme, would then indicate composition, structure and time of formation, as these three properties are inter-related. On the other hand, we can go by mass or diameter and learn relatively little - which I suspect is the way the IAU will go, because that's something astronomers can measure easily. Easy != (interesing || useful). In this case, easy is pretty useless and will be subject to future argument.

I'm sure there are better methods of classifying, but I firmly believe the only useful method of classification is one that will allow predictions to be made and tested. The periodic table of the elements, for example, as a way of depicting valence theory is exceptionally useful. You can make useful predictions about groups of elements or even individual elements, based on the position in the table. Astronomical classifications should be no less useful and (given that we've far more powerful ways of obtaining, classifying and representing data today than early chemists) really should be a far MORE (Moore?) powerful tool.

Re:No other Kuiper Belt Objects have moons?!?

[Rei]

It was more than subtext. How about the episode where Gabrielle, at the end after much buildup, comes out as a "thespian"? Or how about the episode in which Xena has her mind in Bruce Campbell's body, and sleeps with Gabrielle? Or how about the episode where the reality show follows them around discusses the nature of their relationship? It was a running joke that they were lesbians, and there was no attempt to hide it - they played it up every chance they got (one character trapped underwater, another has to dive down and kiss to give air, etc). Check out this search. There was an interview that I ran into a while ago in which one of the creators explicitly stated (to paraphrase) "We've always tried to keep it vague... but yeah, they're lesbians.", but in my attempt to search for it, I ran into some pictures that I distinctly did not want to come across while at a work PC, and terminated my search promptly (you can look for it yourself).