The 11th Planet?

[searcher]

Hello everyone, this is my first post in any forum, anywhere at all, if I'm in the wrong area, or this has been discussed before, I am sure you will let me know.
My question is regarding the recent discovery of the so called 10th planet, but it's not really a planet at all. Maybe they could name it "Clayton".
Now, does this mean that there is a possiblity of more discoveries along these lines somewhere out there, relatively close to us, or are there to be no more surprises.
I look forward to your reply.

[blueshift]

Here is my two cents worth..

There are wobbles that can be detected in the orbits of celestial bodies. Stars have these wobbles as well and they give us indicators when companions are nearby, revolving around them..Along with this, the planets in our solar system are causing gravitational wobbles on each other..The wobbles have patterns that match the movement of the other planets and that can tell us which planet is causing which particular wobble..The planets closest to us with the most mass influence produce larger wobbles than the more distant ones..

The present "10th planet" ( or large Kuiper belt object ) was predicted due to an extra, unaccounted for, wobble in Neptune's orbit..If that new object's wobbles can be all accounted for then there are no other bodies further out. If an extra wobble exists we will be suspicious of another revolving body...

To put it short, it is too early to tell. We need to resolve its behavior with more detail that encompasses the shape of the object's orbit.

[John L]

Blueshift is not correct. The supposed wobble in Neptune's orbit was due to bad old data on Neptune's position. Using only modern data the wobble disappears.

Now, as to a 10th and 11th planet, there are probably dozens of objects half the size of Pluto and maybe half a dozen larger than Pluto that orbit within the Kuiper Belt. Does the fact that they orbit within the Kuiper Belt preclude them being considered planets? Should they be called minor planets, super Kuiper Belt Objects, or all of them just called planets? If we make them all planets then should we make the largest members of the asteroid belt into planets, too?

Beyond the Kuiper Belt it is possible that we will find additional objects that can only be called planets. They are so far away and will be so faint that it will take a very comprehensive survey to find them, but I think we eventually will.

[aeolus]

Originally posted by blueshift@Aug 17 2005, 01:56 PM
The present "10th planet" ( or large Kuiper belt object ) was predicted due to an extra, unaccounted for, wobble in Neptune's orbit.

I think this is Pluto you're talking about.

[Joff]

An alternative, highly anthropocentric, approach would be to discard both Neptune and Pluto from the existing list of planets on the grounds that they are not naked-eye objects. (Uranus I understand can occasionally be seen).

Then we just need an additional generic term for anything that orbits the sun, maybe "heliocentrid". The seven planets from Mercury to Uranus would be heliocentrids as would Neptune, Pluto, Sedna, Ceres, and Halley among thouands of (known) others.

[blueshift]

Johm L,

Thanks for the input..Shows you that I had "old data" rattling around in my head..

aeolus--I was referiing to Neptune, not only repeating what I read a while back but accepting that Pluto might not have given us enough data to verify it..

[GOURDHEAD]

Beyond the Kuiper Belt it is possible that we will find additional objects that can only be called planets. They are so far away and will be so faint that it will take a very comprehensive survey to find them, but I think we eventually will.

I hope before they "find" us. After considering all the junk we have observed and speculated about that is orbiting the sun, can we doubt that each star will have an equivalent amount. If it has not accumulated into objects between Earth and Neptune in mass, we can do it when we get there. I would be shocked and awed if we found any star with a gravity well free of planets or the stuff from which planets can be built. Because of the mutual affinities of the elements that constitute carbon in water based life, we can expect it all over the universe. We must be prepared when they "find" us.

[cran]

Blueshift is not correct. The supposed wobble in Neptune's orbit was due to bad old data on Neptune's position. Using only modern data the wobble disappears.

QUOTE (blueshift @ Aug 17 2005, 01:56 PM)The present "10th planet" ( or large Kuiper belt object ) was predicted due to an extra, unaccounted for, wobble in Neptune's orbit.... I think this is Pluto you're talking about.

... hmm... <_< among the cobwebs in my memory, there did indeed remain an unaccounted for variation or wobble in Neptune&#39;s orbit, after Pluto was factored in; Pluto simply did not display the mass required... turns out the analysts were right, and there was a whole mess of stuff yet to be found beyond Neptune
One presumes that the best estimates of mass and distribution of that &#39;mess of stuff&#39; is included in the modern data, thereby bringing calculation and observation of Neptune closer to agreement...

[cran]

We must be prepared when they "find" us.

What makes you think they haven&#39;t, earthman? h34r:

[ivan]

There are the facts that the 11th planet will be discovered. As you can see, the new 10th planet is not Sedna, the other new planet that just discovered. You can see at my thread "11th planet" that I'm asking a question about this. If the new 10th planet is not Sedna is and closer to the Sun, should Sedna be the 11th planet? And, the problem is the Sedna already be categorize as planet?

[Irishman]

Don't forget Quaoar. You forgot Quaoar?
http://www.gps.caltech.edu/%7Echad/quaoar/

Sedna likely won't be considered a planet (Major Planet) because of the highly elliptical orbit. The IAU hasn't announce it's conclusions yet on just what constitutes a "Planet".

From the layperson's perspective, what is a planet? Some object orbiting the Sun directly, larger than an asteroid* and not spewing a tail like a comet. What category do Kuiper Belt and Oort Cloud objects fall into?

* There doesn't appear to be a solid definition of asteroid that defines it's size, either, so while the IAU is defining "planet" they are by default defining asteroids as well.

Searcher, expect more and larger ones to be found, in the vicinity of where these objects are being found.

GOURDHEAD, it is very unlikely there is anyone* on any of these objects which we are discussing, icy bodies orbiting the Sun. Extra-Solar planets are a different story.

*Anyone means any type of life, especially what we would categorize as intelligent or sentient or sapient, depending upon preference.

[Champion_Munch]

There are the facts that the 11th planet will be discovered. As you can see, the new 10th planet is not Sedna, the other new planet that just discovered. You can see at my thread "11th planet" that I'm asking a question about this. If the new 10th planet is not Sedna is and closer to the Sun, should Sedna be the 11th planet? And, the problem is the Sedna already be categorize as planet?

The new "10th Planet" is designated 2003 UB313, and could be larger than 3,000km, much larger than Pluto. It orbits at nearly 100AU (Astronomical Units, distance from Sun to Earth). Sedna is currently closer to the Sun than UB313 is (around 90AU) and is significantly smaller than Pluto. It is unlikely that Sedna will ever be considered a planet.

Like someone mentioned earlier, Senda's orbit is highly eccentric, and may even be a member of the inner Oort Cloud rather than the Kuiper Belt. For a good indication of how erratic this orbit actually is, refer to this image.

Searcher, expect more and larger ones to be found, in the vicinity of where these objects are being found.

Agreed.

with regards

[jkmccrann]

Some could argue that we already have 11 planets, including the current 9 along with Ceres & Charon (as part of a binary-planet system), but I find that argument kind of hard to stomach.........

[howard2]

What makes you think they haven't, earthman? h34r:

Welcome, but I have to warn you, our atmosphere is only hospitable to entities that can tolerate the highly corrosive effects of oxygen. All living things that have evolved here have mitochondria in every cell to react with the oxygen and give us energy we can use. Without the mitochondria, a living cell quickly shrivels up and dies.
Bearing in mind that our experience shows us that biological entities are adapted extremely specifically to the environment in which they evolved. So it is reasonable to assume that it would be extremely rare for extraterrestrials to find our planet hospitable.
Sorry about that. Happy searching, and give our best regards to The Federation of Planets.

[Disinfo Agent]

Welcome to the forum, searcher. Here's a recent thread about the putative 10th planet.

[ToSeek]

One presumes that the best estimates of mass and distribution of that 'mess of stuff' is included in the modern data, thereby bringing calculation and observation of Neptune closer to agreement...

It was the Voyager flyby that provided a better estimate of Neptune's mass and eliminated the need for an additional planet to explain the perturbations.

[Dragon Star]

In-case you all don't know, Cran had his internet connection zapped some time ago, and I don't know if he has the intention of coming back.

[aurora]

Welcome to the forum, searcher. Here's a recent thread about the putative 10th planet.

Searcher posted two messages back in August, and nothing since.

[Kaptain K]

I see that jkmccrann is back to digging up old threads , even after repeated warnings and a temporary banning!

[Mungascr]

Depends how planet is defined by one definition -

planet = a body that is
* non-self-luminous, (ie. not a star or brown dwarf)
* spherical through self gravity,
* orbiting the sun alone not as a natural satellite of another body,

& also perhaps

- geologically differentiated ie denser materials at the core, less dense materials forming a mantle and crustal layer

Thus we have about 15 planets already :

1) Mercury, 2) Venus, 3) Earth, 4) Mars, then
5) Ceres [poss. five and half, five & three quarters, five & seven-eighths, etc .. some of the other largest asteroids],
6) Jupiter [Or do its radio & IR emissions make it ineligable as self-luminous ie. a brown dwarf?],
7) Saturn [ditto], 8) Ouranos *, 9) Neptune [As for Jupiter and Saturn, Ouranos being the only gas giant that does NOT radiate more heat / energy that it receives from the Sun as I understand it.]
10) Pluto, 11) Quaoar, 12) Varuna, 13) UB313 aka "Xena", 14) one or two of the other recently discovered Kuiper belt /trans-Neptunian objects, 15)Sedna

& perhaps many more as yet undiscovered planets beyond Neptune.

Then again if you set a size limit as defining criteria (radius &/or mass) you can rule out Pluto (Plus the asteroids and Kuiper Belt Objects) leaving just 8 planets - 4 terrestrial worlds and four gas giants or you can count only objects with rocky surfaces ruling the gas giants out as something else .. perhaps mini-brown dwarfs or "failed,failed stars." (Incidentally, why do we call brown dwarfs "failed stars" and not "really successful Jupiters"?)

Or you could do what someone (Isaac Asimov, Patrick Moore, Fred Hoyle?) noted and say the solar system consists of the Sun, Jupiter & assorted debris - in terms of where the majority of our solar systems mass / material is distributed! Needless to say very few people use either of those last two options!

Historically, we've said there nine planets but that now needs updating and revision - unless we replace logic with tradition to keep Pluto in and comparably sized bodies out ... incl. slightly bigger ones like 'Xena'.

My own personal preference? The first definition and lots of planets; why not? It provides for clear criteria that can be easily and consistently applied to define and separate 'planet','moon' & 'star'. Okay it means a few more names to memorise but it keeps things nice and interesting plus Pluto can stay and be joined by others of its class plus the larger asteroids - one for the small planets!

* The more accurate Greek spelling variant of Uranus - which is a semi-romanised form of the original Greek god. It's pronounced "Oo-RAH-noss" stress on the second syllable and puts an end to those asinine jokes about the name of the planet between Saturn and Neptune. Hmm. Then again, we could just rename it Voldemort!

Edited (twice) for atrocius late-night spelling. Make that thrice.

[Mungascr]

Irishman noted Sedna doesn't - or mightn't count - as a planet because of its elliptical orbit.

Well I disagree about that because Pluto also has a very elliptical orbit and one that crosses Neptune's while Mercury also has a fairly eccentric and elliptical orbit. (Mercury's orbit is so odd it inspired Einstein's theory to explain it.) A lot of extrasolar planets have extremely elliptical orbits too - so why is Sedna ruled out on that criterion?

I think orbits matter in that an object orbiting something else directly is termed a moon or natural satellite, (or if really small a moonlet or ring particle) of that object. (Example : our moon orbits the Sun indirectly via orbiting us & therefore isn't a planet! Mercury orbits the Sun directly & so is a planet.) Hence Ganymede and Titan although larger than Pluto and Mercury aren't considered planets but otherwise orbit doesn't come into it. I don't see orbital eccentricity or amount of orbital ellipticity versus circularity as a defining criterion.

What might be more likely to rule Sedna out of planetary status is its size /mass being smaller than Pluto's. However, Sedna is almost as large, presumed spherical and is quite possibly geologically differentiated. All those being points in its favour when taking into account its planetary status claim.

Incidentally the largest asteroid Ceres is also near spherical in shape, thought to be geologically differentiated and apparently contains more water than all the Earth's oceans combined - hence why I'd argue it deserves planetary status - perhaps like Pluto joint planetary / asteroidal status. Don't really see why there can't be such overlap although I admit it can potentially confuse things.

As my last post showed finding where to draw the line between planet and .. well something else ... is a bit debatable; esp. at present until the IAU decides on an "official" definition.

Edited coz I'm over-tired.