New large planets further out in the Solar System?

[RGClark]

Astronomers are Predicting at Least Two More Large Planets in the Solar System.
by Nancy Atkinson on January 15, 2015
http://www.universetoday.com/118252...t-two-more-large-planets-in-the-solar-system/

Bob Clark

 

[Urwumpe]

Astronomers are Predicting at Least Two More Large Planets in the Solar System.
by Nancy Atkinson on January 15, 2015
http://www.universetoday.com/118252...t-two-more-large-planets-in-the-solar-system/

Bob Clark

Such an article pops up every two years and highly surprisingly, such a planet is never found... This one even provides some small orbital data about one of the planets, but I can't read the article for telling how they arrive at predicting a second one by their method.

As I can tell, both studies rely on minor perturbations of the orbits of small objects in the solar system.

[ame="http://en.wikipedia.org/wiki/Kozai_mechanism"]Kozai mechanism - Wikipedia, the free encyclopedia[/ame]

Important is that this theoretical model has a very hard mathematical limit: It expects a restricted three-body problem. The further you go away from the restricted three-body problem in the observation data (more than one large planet and the sun, or no longer a significant difference in mass between the planet and the object of study), the less can the mechanism be used as explanation.

So... should somebody find a link to the full article, I would really like to read it, but I have not high hopes, that this is not one of the "we still exist and we need more funding" articles, that flood the journals during the cold and dark season.

 

[PhantomCruiser]

Maybe it's just Russell's teapot, but further out than he'd thought. :dry:

 

[fsci123]

http://arxiv.org/pdf/1406.0715v2.pdf

This may be it

 

[MattBaker]

Not that hard to believe, Sedna's orbit for example:

An orbital period of over 11,000 years and we only know about it because it's going to be at perihelion later this century. Why shouldn't there be a similar, or even bigger, object that is at aphelion right now? It could have been last at perihelion and somewhat visible (for modern technology) at times like 2,500 years ago, when astronomy was limited to human eyes.

 

[Urwumpe]

"Using a Monte Carlo approach, we create a synthetic population of ETNOs with semimajor axis..."

Ouch.... :facepalm:

So, they first of all create a huge random cloud of simulated particles with some position and velocity constraints. Then they propagate each of this particles until it reaches perihelion. They cite all the assumptions behind the approach, so its easy to empirically check the data with slightly different assumptions.

And then compare the idealized monte-carlo population with the real planets and note differences. And of course there are differences, since there is no reason to assume that the Monte-Carlo-population is extremely accurate.

 

[statickid]

I feel like it would be just as good an argument to say "It's improbable that we've discovered EVERY sun-orbiting body in the solar system." :lol:

 

[Urwumpe]

I feel like it would be just as good an argument to say "It's improbable that we've discovered EVERY sun-orbiting body in the solar system." :lol:

Exactly - its no theory that you can use for finding the planets.

 

[RisingFury]

And then compare the idealized monte-carlo population with the real planets and note differences. And of course there are differences, since there is no reason to assume that the Monte-Carlo-population is extremely accurate.

Now you're just talking out of your ass.