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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.""
Nothing for you to see here. Please move along.
You can't handle the truth.
Now that Pluto's been confirmed to have more than one moon, what will than mean for the old debate over whether Pluto or Charon's the actual planet? Ought to be fun to watch...
Creative misinterpretation is your friend.
There will be no moon probing while I'm around!
So not official. RTFA. That's no moon....that's a canditate.
And they are still going to scrap this suck-ass telescope, right?
12:50 - press return.
Nice? The photographs are a bunch of small white dots! Does anyone else see real photographs? I guess he is referring to the "artistic conceptual drawings"
"Yeah...I'm tired of probing Uranus."
For now, Pluto is the only Kuiper Belt object known to have satellites.
My good friend UB313 would have to disagree.
There are actually several known KBOs with moons. Or was the submitter being overly litteral and meant multiple moons?
Unlike what the poster said, Pluto is not the only one with a moon.. html
Various other KBOs do, including Xena :
http://www.planetary.org/news/2005/xena_moon_1003
I hope we have our XK-PLUTO nuclear-powered bombers ready for the Old Ones. Me? I'm going to take a little trip to XK-Masada.
Pluto now officially has three moons
More like "four big asteroids are gravitating around each other beyond the orbit of Neptune".
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Pluto is a planet, not an object. Anything else is either cultural revisionism or solar system wide discrimination.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
...it's not even official yet. The objects are believed to be orbiting Pluto, but there has been no independent confirmation they actually are, and the IAU hasn't (yet) responded to the submitted claim.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Does that mean we can call them "Cerebus" collectively?
"In the game of life, someone always has to lose. To me, if life were fair, that someone would always be Oklahoma." -DKR
...do even the jokes have dupes?
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Seems hubble is doing something useful every time you turn around. And NASA says the Hubble Telescope needs to be retired.
Click Click Bloody Click PANCAKES!
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-
So does this mean that Pluto is NOT a moon itself? I didn't know the discussion/debate was officially over.
this is a good idea
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.
I hate the one hundred and twenty character limit for signatures with an all-enveloping, all-destroying, incredible pass
The slashdot article says Pluto is the only Kuiper Belt Object to have a moon. Not so: Tenth Planet Has A Moon
And what of astrologers the world over. Apparently my governing planet is pluto and we scorpios like to fondle our dicks. What does a new moon mean?
has really caused us a lot of grief in classifying heavenly bodies and discovering them. Not only does it interfere with scientific terminology, it hampers understanding of average people. We should just kick Pluto out and accept that we have 8 planets, not 9. Everyone would be happier (except Pluto).
...on where it kept them. The underworld is a BIG place to hide things you don't want discovered.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Even if you rolled all the rockets we have ever launched, and all the fuel we packed into them, I doubt it they would form a sphere even a single kilometer in diameter.
A Saturn V was about 20 meters in diameter, and about 100 meters tall, more or less. Volume of a cylinder is pi r^2 * length. That would make the volume of a Saturn V about pi * 2500 meters^3.
The volume of a sphere is 3/4 * pi r^3. The volume of a sphere one kilometer in diameter would be pi * 93,750,000 meters^3. That would be volumne of something like the prelaunch volume of 37,000 Saturn Vs. The payload of a rocket is a fraction of the mass of the entire thing. Let's say 1%. Most rockets are much smaller than a Saturn V. Payloads launched into low earth orbits decay within decades, like Mir, or Spacelab.
It wouldn't surprise me if the volume of all the working satellites, and space detritus, that remain in orbit would be less than the prelaunch volume of a single Saturn V.
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
Oh please, 'twas but a mere breeze. That hangar's falling apart anyway.
Mix the failings of Usenet with the shortcomings of the World Wide Web and the result is slashdot.
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.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Calling it a 'moon' implies that it orbits something which orbits the Sun. Calling it a 'rock' wouldn't.
First the dumbass submitter uses US units with metric in parenthensis, then switches to metric with no mention in US units. What the fuck? This story happened in the US - don't use metric units, dipshit.
It is clear that it did not form from the same planetary disk that spawned the planets from Neptune on in.
I don't understand this, can you elucidate? Are you saying there was another planetary disk at some other time? Or that Pluto and friends wandered in from interstellar space?
If Pluto can get more moons, maybe Earth will start getting some new ones too!
That'll be helpful when we've run over our current moon and can't fit any more people on it anymore.
Can't you tell?
What happened to the one they sent to URANUS?
"You're everywhere. You're omnivorous."
How does the moon's distinct lack of heavier elements fall in line with the moon being created at the same time?
Well, there are usually two aspects to the impact ejection theory. The idea is that the earth was struck and:
1) ejected dust that formed the moon and
2) knocked the earth's axis so that it we have the tilt that generates the seasons.
Now, there are two issues that I have with this theory:
First, it presumes that the earth's equator was very close to the ecliptic. This is not something I can take for granted given that the tilts of other axes are:
Neptune: 30 degrees
Uranus: 98 degrees
Saturn: 25 degrees
Jupiter: 3.1 degrees
Mars: 25.2 degrees
Venus: 177.36 degrees
Mercury: 0 degrees
Of the eight major plants, axis tilts are sufficiently low to allow for this sort of idea only on Jupiter and Mercury. It seems unreasonale to me to think that planets such as Saturn were somehow knocked off axis by impacts. Also Venus has no moon and it seems unreasonable to indicate that it was knocked off its axis. Instead the axis of rotation seems to have been decided on a local variation.
Even if one imagines that the earth had a very low axis tilt originally, the ability to simultaniously eject enough dust to cause the moon to form witnin six degrees of the ecliptic seems a bit of a stretch to me, especially since such an impack would *also* have had to occur nearly exactly on the equator and still managed knock the earth off its axis.
The reason why these objections have generally been disregarded by the astronomical community is a theory which posits that a type of asteroid called "carbonaceous chondrites" formed the original planetessimals from which all rocky planets originated. While mercury never fit this model, it was generally assumed that these formed the basis for Venus, the Earth, Mars, etc. It was therefore believed that one would be able to form models of the interior structure of Mars consistant with the projections of this theory. As the moon clearly didn't fit, the impact theory nicely solved this problem.
However, it now appears that the idea that carbonaceous chondrites form the basic building block from which rocky planets were formed has now had some very large holes torn in it in that no model which fits the existing data on Mars can support this theory of the formation of Mars. Absent this theory, I can think of no good reason to subscribe to impact-emission theory of lunar origins, as it seems simpler to think that the moon may have formed as a smaller dustball forming from lighter particles which ended up further from the early earth in the same way that the structure of the gas giant systems (the outer planets and their moons) mirrors structurally the Sun and inner planets.
I could be wrong as I have no astronomy degree, but at least it is informed inaccuracy....
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All right, I can understand that Jupiter, Saturn, Uranus and Neptune have zillions of moons because they're big mommas with a lot of gravity, and when you're very generously rounded -- well, you just naturally attract a lot of trash. Fact of life.
But now even puny Pluto is getting into the act. Three moons, when Mercury has zero and Mars but two. What gives? Why are moons more common in a general way in the outer Solar System than the inner? This is odd. Is it all captured from the Kuiper Belt? Did the solar wind when the Sun was T-Tauri blow all the moon-making crap out of the inner system, but not the outer? Is there some reason why whirlpools in the nebula are more probably further out? Inquiring minds want to know!
..then it's lowercase-k, and a space between the number and 'km'. Uppercase-K means kelvin.
Is this just an attempt to keep Pluto in the "planet" catagory? Because it seems like someone says "So what makes Pluto so special? We've got dozens of KBOs that big and bigger" and some people refuse to consider the idea that Pluto is nothing special. Now we suddenly have 3 moons on Pluto?
I don't know. I'm probably just crazy, but it seems possible to me.
*ducks*
Obligatory Soundbite Catchphrase
Jupiter, Saturn, Uranus, Neptune, and of course the Sun.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
that other body have a moon? Xena or somethin' ?
Is this anything like the probe placed "inside" Cartman?
Does God treat us as servants or friends? Check my homepage.
1) The impactor, known alternately as Orpheus or Theia, has been modeled to have been about the size of Mars, and to have hit Earth at a very oblique angle. 2) The absolute best evidence we have for the theory is that the moon has essentially no iron core. All the other terrestrial planets do. As it turns out, the comosition of the moon is remarkably similar to that of Earth's mantle (oxygen/silicon). It is theorized that most of Theia's core merged with our own. Earth's mean density is, if I recall, something on the order of 5500 kg/m^3. The moon has a mean density of something like 3300 kg/m^3. If you were to take out the Earth's iron/nickle core and replace it with mantle material, it would have a mean density similar to that of the moon. 3) As an astronomy minor and having taken planetary formation courses, I've never heard anything about carbonaceous chondrite cores forming the basic building blocks of planets. Carbon, counterintuitively, isn't even too abundant on Earth. Or anywhere else for that matter. Or rather, there certainly is a lot of it, but not compared to oxygen, silicon, iron, aluminum, etc. 4) You can't compare the models of planetary formation in the inner solar system to the outer. Not on a 1:1 basis. The outer planets are significantly larger than the inner because they formed past the frost line (about halfway through the asteroid belt). After this line, ice stays in crystalline form, allowing the rocky starts of the other planets to aggregate much more mass, both planetary and gaseous (the rocky core of Jupiter, at least, is probably about 20 times the size of Earth). With this much more mass, they can more easily capture smaller planetismals, which become moons. It would be far, far easier for a Jupiter to capture Luna than for Earth. 5) As alluded to in the beignning of this post, computer simulations have been done on both the capture and impact theories (including many variations of). The impact theory works. The capture does not. 6) That we have plate tectonics, significant ocean basins, etc, could also be construed as evidence for the giant impact theory. Venus has no moons, and there is little evidence that it ever underwent plate tectonics. The same goes for Mars, and I assume Mercury, though I am not sure on the latter. But the most important thing here is #2. That's the smoking gun.
Sorry, forgot to format it. Hope you guys can follow.
Can we have this in imperial units, this is an American website and an American space program we're talking about here...
Does anyone other than this British guy find this comment deliciously ironic?
I'm not an astronomer either, having just taken a couple of courses in college, but my professors seemed to frame the massive impact theory as more 'the best explanation we have for right now.' It had the advantage of explaining things like the size of the moon, the composition, its unusual distance and orbital velocity (which just don't fit for a capture). It's not perfect (especially if the larger solar system creation model doesn't hold up), but it's the only explanation that doesn't have especially glaring holes in it.
hot foreign sheep.
The Mi-Go might find out about us...
I'm afraid of their brain canisters!
Does this mean a return to the theory that the Moon was scraped out of what's now the Pacific basin? IIRC, that was one of the earliest theories for its origin, sometime in the nineteenth century.
Media that can be recorded and distributed can be recorded and distributed.
-kfg
That's a pretty good summary, but people should know that Mars has two moons. However, they're not nearly as big as Earth's moon and are probably captured asteroids, not the result of a giant impact, so they don't invalidate this theory.
I also am not an astronomer, so this may be a dumb question, but how do you get an axis tilt of 177.36 degrees? Surely this is a tilt of 12.64 degrees. So do you use the magnetic poles as the reference; but in that case, when Earth switchs it's magnetic field, will all these axis tilts then be incorrect, or what if the other planets also have magnetic fields which switch?
The other alternative I see is on direction of rotation, but if that is the case, Venus also has an equator near the elliptic - just spinning in the opposite direction to us.
To be is to do - Descartes. To do is to be - Sartre. Dooby dooby do - Frank Sinatra.
Not that the LANGUAGE of science uses kilometers, meters and all that wonderful other metric stuff, right? Why do you think all basic science classes in US public education forces us to learn all those conversions from MM to CM to meters and beyond? Or was my boondocks of a school district just that far ahead?
I'm an American. Big deal if they use something other than Imperial measurements, scientists use metric (and the US should use metric for so many reasons, anyway). Go use Google, something of a query like "122KM to MPH" or "83M to FT"