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View Full Version : Is Sedna planet X



errorist
2004-Mar-15, 05:29 PM
Is it coming towards us?? They said it has a very large elliptical orbit.

http://www.space.com/scienceastronomy/new_...ect_040315.html (http://www.space.com/scienceastronomy/new_object_040315.html)

jonfr
2004-Mar-15, 05:48 PM
The gravety needs to be huge for the planet to be going into our solar system, i doubt it.

errorist
2004-Mar-15, 06:11 PM
Comets do it all the time???

zrice03
2004-Mar-15, 07:52 PM
This world is not coming into the inner solar system. It's closest point is actually right around now. Comets are little dinky bits of ice and rock that are easily disturbed by the gravitational effects of other comets and objects like Sedna, here. Sedna, on the other hand, is way too massive to be affected by what's out there.

Think of using a telephone pole to swing around like kids do sometimes, then think of trying to do the same thing with a drinking straw. Disrupting Sedna would be like you and the straw. (i.e. it won't work...)

Faulkner
2004-Mar-15, 07:55 PM
Interesting comment tho', I'd like to see the orbital trajectories plotted out...!?

antoniseb
2004-Mar-15, 08:05 PM
Originally posted by Faulkner@Mar 15 2004, 07:55 PM
Interesting comment tho', I'd like to see the orbital trajectories plotted out...!?
The orbit is plotted out on the Spitzer observatory website.
Basically, it will reach perihelion in 72 years at about 76 AU, and then head out for the next 5000 years to about 850 AU.

VanderL
2004-Mar-15, 08:43 PM
Ok Antoniseb, let's rephrase the question: could it have been Planet X?

Cheers.

errorist
2004-Mar-15, 09:07 PM
If not this one, perhaps the next one they find will be???? Or have they found it and are not telling us???

antoniseb
2004-Mar-15, 09:36 PM
Originally posted by VanderL@Mar 15 2004, 08:43 PM
Ok Antoniseb, let's rephrase the question: could it have been Planet X?
Unfortunately, the reference seems to be lost on me. The implication in this thread seems to be that Planet X is something destined to hit the Earth, but in all the cultural references I recall, it was merely a mysterious planet in the dark reaches of the solar system perhaps people by evil aliens who loved the cold and dark [or sometimes around another star].

errorist seems to be asking if:
- there's a chance that such an object is coming this way, and
- someone on Earth knows about it, and
- they're not telling us about it.

I understand the concern, but fortunately the answers are:
- about one chance in a quadrllion years [with wide margins of error]
- no, no one on Earth knows about such a thing. We are incapable of keeping THAT kind of secret for long.
- yes, if someone does know about such a thing, they haven't tried to sell the story to the press yet to gain financial well-being during the last years of our existence.

Let me go back to that first answer. The most likely way for one of these things to come down and hit us is for two of them to interact near the aphelion of one of them in such a way that the smaller one loses just about exactly all of it's forward orbital motion [a pretty unlikely maneuver]. It would then start the 5000 year fall in toward the sun. The Earth takes up 50 parts in 1e18 of the target area. This object gets two shots at us. If it misses, it will be one SPECTACULAR comet.

VanderL
2004-Mar-15, 10:04 PM
Sorry Antoniseb, I was just speculating on the Planet X story of Sitchin and the likes (Sitchin concluded this from old Babylonian tablets). He and others believe that Earth was repeatedly visited by ET's from Planet X, which returns to Earth every 5000-some years and my question was more meant as a comment on the trajectory of this unknown planet. Could it have changed from an Earth-crossing (cometary) object into the orbit that is seen now. Btw, apart from the interesting interpretation of the tablets, Sitchin's ideas are as far from reality as Sedna's orbit. ;)

Cheers.

Duane
2004-Mar-16, 09:46 PM
it will be one SPECTACULAR comet.


Holy crap yea, it would outshine everything but the sun--from the orbit of Jupiter! Be scary to see what it might bring with it, comets and the like......

Mettalica1
2004-Mar-31, 08:08 PM
No i dont think that Sedena is planet x!!

Planetwatcher
2004-Mar-31, 09:47 PM
In a manner of speaking it is.

damienpaul
2004-Apr-01, 08:35 AM
What manner might that be Planetwatcher? and we are still waiting for your pic :P

galaxygirl
2004-Apr-04, 01:42 AM
Wow, I'm confused. I always thought that Planet X was this large, distant planet that was effecting the orbits of Uranus and Neptune... :huh:

damienpaul
2004-Apr-04, 02:02 AM
Exactly my thinking galaxygirl, with the addition of perturbing all the KBO's etc

galaxygirl
2004-Apr-04, 02:19 AM
So how could Sedna be planet X? It's too small to have any affect on Uranus and Neptune.

Planetwatcher
2004-Apr-04, 08:29 AM
That would be Nemesis that perturbs Uranus, Neptune, Pluto and KBO.
Planet X to my understanding is simply the tenth planet.
Although their is some disaggreement of wheither or not Sedna should be considered a planet, I believe it should have duel citizenship as a planet and a KBO, just like Pluto.

And damienpaul I just posted my picture, except I just happen to have had my mask on. :lol:

DippyHippy
2004-Apr-04, 11:04 PM
I don't think it should be classed as a planet because it's too small and the orbit is too eccentric. I think pretty everyone (that I know of) is agreed that it's most likely the first confirmed KBO to be found.

Likewise, if Pluto were discovered today I'd say the same about that. I used to think that it should still be classed as a planet, but to be honest, I think it should have duel citizenship now.

Helios
2004-Apr-11, 04:00 PM
I guess all astrology has always been wrong, leaving out an entire planet and all.


Sedna backwards is Andes

KeiZka
2004-Apr-11, 08:16 PM
Originally posted by Planetwatcher@Apr 4 2004, 08:29 AM
That would be Nemesis that perturbs Uranus, Neptune, Pluto and KBO.
Planet X to my understanding is simply the tenth planet.
Although their is some disaggreement of wheither or not Sedna should be considered a planet, I believe it should have duel citizenship as a planet and a KBO, just like Pluto.

hm, not to forget quaoar. there was some arguments about it, but they apparently didn't make it as planet. seems it's happening again with sedna... (oh, and quaoar was momentarily, thanks to media, planet x. let's hope media doesn't do same with sedna...)
But referring to Nemesis, i don't know what to think about it. Surely, it can be there, but i find it rather improbable. To think about how fast humankind has developed means to watch starry sky, i think it should've been noticed already... (ok ok, i admit i'm again on my lil' crusade against something i find irregular... but... i get some fun out of it, so don't pay attention to my drabbling :lol: )

DippyHippy
2004-Apr-13, 11:20 PM
I lay the blame for Sedna's alleged planetary status entirely at the feet of NASA because they hyped up the announcement. It was blown totally out of proportion. Before you knew it, there were news stories in the Australian and British media telling the world that a 10th planet had been found and it was purely due to the shambolic way the announcement was made.

Oh well... it'll make for an interesting chapter in a book one day LOL

Tim Thompson
2004-Apr-16, 12:16 AM
Originally posted by galaxygirl@Apr 4 2004, 01:42 AM
Wow, I'm confused. I always thought that Planet X was this large, distant planet that was effecting the orbits of Uranus and Neptune... :huh:
The perturbations of the orbits of the outer planets, which motivated the search that discovered Pluto (http://dosxx.colorado.edu/plutohome.html), never actually existed. The disturbance manifests itself as a difference between the observed position of the planet, at any given time, and the theoretically predicted position. But the theoretical prediction requires a proper knowledge of the masses of the planets. Those masses were not known with sufficient precision until the Voyager spacecraft (http://voyager.jpl.nasa.gov/) visited the outer planets in the 70's & 80's. The trajectory of the spacecraft around the planets allows for a precise determination of the planetary masses. Once those newly determined masses were substituted for the previously used masses, all of the perturbations vanished in the noise. As it stands, there are no unexplained perturbations to the motions of the outer planets, and so we know that there are no nearby, large planets left to discover (see the paper Planet X - No dynamical evidence in the optical observations (http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1993AJ....105.2000S&db_key=AST&high=3e6fbfd69f22134), E. Myles Standish, Astronomical Journal (http://www.journals.uchicago.edu/AJ/) 105(5): 2000-2006, May 1993; Standish is a long time member of JPL's Solar System Dynamics Group (http://ssd.jpl.nasa.gov/group_home.html), and a leading expert on planetary orbit computations).

As for whether or not Sedna (http://www.gps.caltech.edu/~mbrown/sedna/) (the Inuit Goddess of the sea (http://www.hvgb.net/~sedna/story.html)) should be a "planet" (or even Pluto (http://www.nineplanets.org/pluto.html), for that matter), it all strikes me as a useless exercise in semantics. For instance, since when is planethood an either-or option? Why can't Pluto, for instance, be "the smallest planet" and, at the same time, "the largest KBO"? I don't see any problem there, and I don't think Clyde Tombaugh (http://www.klx.com/clyde/), were he here, would object to this kind of planetary dual citizenship.

Then there is the problem of coming up with some objective, hopefully "rigorous" definition of "planet". I prefer the idea put forth by John Stansberry (http://rincon.as.arizona.edu/~stansber/), at the University of Arizona, Steward Observatory, in his "Pluto is a Planet (http://rincon.as.arizona.edu/~stansber/PlutoPlanet.html)", namely, if its big enough to pull itself into something close to a sphere (the minimum energy configuration for any gravitating body), then it's a planet. Sedna (http://www.nasa.gov/vision/universe/solarsystem/planet_like_body.html) is too far out for us to tell yet, but even the largest asteroids (http://www.nineplanets.org/asteroids.html) are definitely potato shaped.

Hoore500
2004-Apr-16, 09:59 PM
Sedna is at least the third new body in Solar system behind Pluto.
Here you are some planetX pics I would like to share with you. Please take a look to them, my student adviser says this is only art. (http://uk.geocities.com/any_who2001/art.html)

:lol: Any of your reactions is welcome to me. I just embrace you my sweetie peetie yankee people.

antoniseb
2004-Apr-17, 12:57 PM
Originally posted by Hoore500@Apr 16 2004, 09:59 PM
... my student adviser says this is only art.
Your student advisor is right. They are nice images, but they are not pictures of Sedna or the other Kuiper Belt Objects [note that there are hundreds of known KBOs further away than Pluto].

If you created these images yourself, and are looking for pointers on how to make a better fake, here's a few tip-offs that these are not pictures of Sedna or anything like it:
- See the best image of Sedna taken by Hubble http://www.universetoday.com/am/publish/hu...na.html?1442004 (http://www.universetoday.com/am/publish/hubble_looks_sedna.html?1442004)
- these are color images, but all the stars are white
- this is a very deep image, but there are no background galaxies
- the stars of the second and third images are the same star-field with a few extra stars in the second image not appearing in the first

Anden
2004-Apr-18, 12:25 PM
Hasn't a new KBO just been discovered as in the month or something?

lightyear77
2004-Apr-18, 12:35 PM
Hi everyone,

I wonder, if they`ve find Sedna way out of the "normal" orbit that earth and the other planets have, will they focus on odd elliptical orbit to find new "planet" or planetoid" like Sedna. I think if they find others like Sedna who have the similar size, it will play a big role whether it`s a planet or not.
I wouldn`t mind thinking our solar system is a 10 planet system, wouldn`t you? B)

Anden
2004-Apr-18, 12:38 PM
Lol. Nice and metric?

astronaut
2004-Apr-21, 05:01 PM
Originally posted by galaxygirl@Apr 4 2004, 01:42 AM
Wow, I'm confused. I always thought that Planet X was this large, distant planet that was effecting the orbits of Uranus and Neptune... :huh:
One thing I can say: I read Sitchin's book, and his work is really something interesting. We can't say now wether Sedna is planet X or not, but I'm convinced there's something out there we're still about to discover, might be in days, in years, but it should happen...
Humanity's creation and past is for sure terribly clear, and people like Sitchin, who work seriously on the topic, are starting to incentivate people to open their eyes and start looking for answers.

RUF
2004-Apr-21, 11:13 PM
It's a large rock, just like Pluto/Charon are.
I think I read somewhere that it may also have a closely orbiting moon, like Pluto and Charon.
Can anyone tell me if they heard that too?

Sp1ke
2004-Apr-21, 11:55 PM
I wouldn`t mind thinking our solar system is a 10 planet system, wouldn`t you?

Or if you're working in Imperial units, there must be another two planets out their for a nice round total of 12
:D :D

Starry7
2004-Apr-22, 12:32 AM
Maybe the whole question of what a planet and what a KBO is will be solved with the New Horizens probe going to Pluto in a few years? I have no problem with both Pluto and Sedna being both a planet and a KBO, but there has to be a way to distinguish between the two. Anyone know what the criteria are?

GOURDHEAD
2004-Apr-22, 02:42 AM
For those who are interested in whether a stellar orbiting body is a planet or not I suggest categories of planets with earth as a standard as follows:

Hyper planet Above 10 jovian masses and below 100 jovian masses or
the mass at which sustained fusion of hydrogen begins

Super planet one to <10 jovian masses

Large planet 10 earth masses to < 1 jovian mass

Planet 0.5 to < 10 earth masses

Hypo-planet 0.01 earth mass to < 0.5 mass

Micro-planet < 0.01 earth mass

The above categories will provide a useful set of handles and preserve the meaning of the word planet as wanderer which each stellar orbiting object satisfies.

Asteroids would become non-stellar objects in their own galactic orbit.

Greg
2004-May-02, 05:01 AM
Not a bad system. As of now there is no standard definition of a planet, so this is better than what we have now.
This is a fairly significant problem since scientists communicate ideas and measure things based on accepted standards. Now that more and more objects are being discovered, both larger and smaller than what we think of as planets, people are realizing that a standard definition is long overdue and will be sorely needed as more "objects" are discovered, both big and small. To be honest, I personally have a problem with naming a spherical object a planet when it is smaller than our own moon.
The KBO definition as based on location and composition than mass, but mass seems to apply to them as well in that they are smaller than alot of moons. An ideal categorization might have to take into account all of these considerations. If we use diameter or mass alone we might consider Mercury too small to be a planet, but its location, composition, and orbit clearly relate to that of the other planets.

Greg
2004-May-02, 05:14 AM
Regarding the Nemesis theory, it is a wild idea at this point, but not entirely excluded from the realm of possibility. After seeing HST&#39;s photo of a gas giant being ejected from a young star system, I realized that the interstellar medium is probably populated with a significant number of lonely wanderers.
If these gas giants have moons as they often do, there could even be heat driven (tidal) life on those moons.
But I shall not digress on that further. It is not inconceivable that a formerly wandering planet may be locked in an eccentric and long orbit around our star not necessarily in the same plane of orbit as the other planets. I think it is less likely that a gas giant was ejected from our system unless it was very early. Such a planet could stir up the ort cloud and move comets our way from time to time, but I think the whole thing is a longshot. We should be able to spot it eventually by looking for clear paths through the ort cloud debris or with ever more powerful telescopes, but I wouldnt hold your breath on discovering anything much larger than pluto.