Unpredictable Trinary Exoplanets

[CraigS]

The conjugate of what is reported in the 'Earth's Orbit Unpredictable !' thread ….
New planet discovered in Trinary star system

Until recently, astronomers were highly skeptical of whether or not planets should be possible in multiple star systems. It was expected that the constantly varying gravitational force would eventually tug the planet out of orbit. But despite doubts, astronomers have found several planets in just such star systems. Recently, astronomers announced another, this time in the trinary star HD 132563.
…
With the discovery of this new planet, the total number of discovered planets in multiple star systems lies at eight. While this is rather small numbers from which to draw firm conclusions, it appears that planets can be commonly found orbiting the more remote members of trinary star systems for good periods of time. On the shorter end, the stellar system is anticipated to be 1-3 billion years in aged, based on the amount of stellar activity and amount of lithium present in the star’s atmosphere (which decreases with time). However, fitting of the mass and luminosity onto isochrones suggest the stars may be as much as 5 billion years in age.

In either situation, the planetary system is dynamically stable.
Also based on these eight systems, the team also suggests that planets existing around such far removed members of a multiple star system may be as common as planets around wide binaries, or even single stars.

The bottom line is that purely deterministic physics models in this instance, did not make accurate predictions for the existence of stable planetary orbits. This is exactly what chaotic models tell us, however … ie: chaos and order will occur and we cannot predict where or when it will occur.

Cheers

[renormalised (Carl)]

The have to remember, because they have seem to have forgot their basic maths for planets in orbits around multiple stars, that stable orbits will occur around the stars in multiple system where the planets orbiting in the plane of the system are equal to or less than 1/5th the distance from their parent star as the minimal distance between the stars in their orbits.

Despite star A being a binary, if they're close enough together they will appear as one body gravitationally to the other star B and to any planets orbiting that star. It appears that they are. So, for star B, if the minimal distance between stars A and B in their orbit were, say, 300AU, then the planets of star B could exist in stable orbits out to 60AU, providing they orbited in the plane of the system as whole. If they orbit at high inclinations to the system, the orbits become unstable at much closer separations because the planets are open to the gravitational influence of the component stars more severely. Other stable orbits will occur if the planets orbit the barycentre of the entire system. i.e. they orbit the centre of gravity of the all three stars instead of just one or more components of the system.

However, chaotic motions in the orbits can still occur no matter where they orbit in the system.

[Zaps]

"...because they have seem to have forgot their basic maths..."

Yes, I'm sure that's the case.

[CraigS]

PS: The paper is here.

Cheers

[renormalised (Carl)]

Originally Posted by Zaps

"...because they have seem to have forgot their basic maths..."

Yes, I'm sure that's the case.

Instead of trying to be funny all the time, why not actually contribute to a discussion.

They forget their basic maths simply because, in one breath, they calculate the possibility of stable orbits around stars in multiple systems and write copious papers on the subject. Then, when they find a planet orbiting a multiple system of stars (be it a binary, trinary or more) they feign surprise and then go onto say it was something wholly unexpected because "theory" can't explain why they're there. Either, they're forgetful of previous work done or they don't understand what they're on about and just blow smoke when the occasion arises. Either they don't know which theory to use or all the previous work was a waste of time because they're not going to use it, anyway.

Until recently, astronomers were highly skeptical of whether or not planets should be possible in multiple star systems. It was expected that the constantly varying gravitational force would eventually tug the planet out of orbit. But despite doubts, astronomers have found several planets in just such star systems. Recently, astronomers announced another, this time in the trinary star HD 132563.
…

There's direct proof....it's pretty obvious that their previous skepticism was based on nothing more than not having observed these planets and a case of not fully understanding the dynamics of the physics in these systems. In reality, considering those studies which pointed to stable orbits in multiple star system, it was a case of being too skeptical (read narrow minded) to consider the possibility. Fact is, they exist and now they will have to do the maths in order to understand the physics of these systems.

[renormalised (Carl)]

Originally Posted by CraigS

PS: The paper is here.

Cheers

Thanks, Craig

[Zaps]

Originally Posted by renormalised

They forget their basic maths...

Laughable hubris on your part.

[renormalised (Carl)]

Originally Posted by Zaps

Laughable hubris on your part.

And all I see of you is your arrogance and feigned aloofness. If you don't want to contribute, don't bother. Stay being your "retired scientist". But don't bother to make little facetious comments just because you think its smart. Go find someone and somewhere else here to annoy.

[CraigS]

I think the article may be suffering from either poor journo wording or translation issues.

The paper is far better reading.

Cheers

[renormalised (Carl)]

Originally Posted by CraigS

I think the article may be suffering from either poor journo wording or translation issues.

The paper is far better reading.

Cheers

I agree. I had a quick read of the paper late last night. It's far clearer when it comes to their premises, methodologies and observations. It's very much apparent that the journos have added their "two bits" to the interpretation of what was actually done and what was conveyed to them.

You know, I just wish for once, that journalist would report things factually and in a completely "uninterpreted" manner.