Detached Objects (DOs)

[dougettinger]

Does anybody in the Forum have any ideas about the origins of solar system detached objects (DOs) ?

Very, very curious,

[Chris Peterson]

Does anybody in the Forum have any ideas about the origins of solar system detached objects (DOs) ?

In terms of origin, why would you expect them to be any different from all the other TNO and scattered disc objects? It is an inevitability of orbital mechanics that some will be detached objects- it's just a matter of position and orbital elements, both determined by the perturbation history of the objects.

[dougettinger]

Hello Chris,

I am not sure when this recent term of DO's came into being, but the DO's are differentiated from scattered disk objects (SDO's) by their anomalous orbits. Per the DO's definition their orbits are not derived from ejections by the Sun or the outer planets. Their orbits are definitely thought to be derived by capture from interstellar space. Presently, this is the conclusion with the tracking of their trajectories. The other fact about DO's is that they are like KBO's (dwarf planets) and not like comets.

We have had these discussions before about the probability of capture of celestial objects by our solar system from interstellar space. At that time I was not aware of DO's.

So my question still stands. Where did these DO's come from?


Truly a non-believer of the Oort Cloud,

[Chris Peterson]

So my question still stands. Where did these DO's come from?

Exactly where I said. It is an inevitability of orbital mechanics that some TNOs and scattered disc bodies will end up in DO orbits simply due to perturbations over the history of the Solar System. DOs are not any different in origin than any other TNOs.

[dougettinger]

Please excuse my ignorance. What are TNOs?

I have my own reasons for believing that DO's originated elsewhere other than from our solar system and its formation process.
However, I am paraphrasing Wikipedia about DO's source coming from interstellar space. Perhaps this scientific opinion has already changed.

Non-believer of the Oort cloud,

[Chris Peterson]

Please excuse my ignorance. What are TNOs?

I have my own reasons for believing that DO's originated elsewhere other than from our solar system and its formation process.
However, I am paraphrasing Wikipedia about DO's source coming from interstellar space. Perhaps this scientific opinion has already changed.

TNOs are trans-Neptunian objects, the name given to all the icy bodies orbiting outside Neptune's orbit. They are typically classified into three zones- the Kuiper belt, the scattered disc, and the Oort cloud. There's nothing to suggest that these bodies differ in origin, but are simply dynamically distinguished. Where one of these early-formed icy bodies ended up depends on its perturbation history over billions of years (although primarily during the first billion years of the Solar System).

Detached objects are also a small classification of TNOs dynamically distinguished by their large perihelions.

[dougettinger]

Thanks for telling me what TNO's are: I should have known the term. You avoided my one comment about Wikipedia explaining that DO's are from outside the solar system. Did I mis-interpret Wikipedia's explanation?
Doug

[Chris Peterson]

Thanks for telling me what TNO's are: I should have known the term. You avoided my one comment about Wikipedia explaining that DO's are from outside the solar system. Did I mis-interpret Wikipedia's explanation?

I don't find any reference in a Wikipedia article to DOs being extrasolar in origin, nor have I heard it suggested before, nor is there any good reason to believe that, given that capture of interstellar rogue bodies is dynamically unlikely.

Spectroscopically and dynamically, DOs appear to be no different from other TNOs, other than having been perturbed into slightly odd orbits- a process that is much easier to explain than how they would be captured bodies.

[dougettinger]

Hello Chris, I will quote Wikipedia (detach object) which led me to think that DO's could truly be detached. I realize that Wikepedia is not the best authority to cite, but the free encyclopedia does certainly help to keep topics current.

"Such orbits cannot have been created by gravitational scattering by the gas giants (in particular Neptune). Instead, a number of explanations have been put forward, including the encounter with a passing star or a distant planet-sized object."

Doug

[Chris Peterson]

Hello Chris, I will quote Wikipedia (detach object) which led me to think that DO's could truly be detached. I realize that Wikepedia is not the best authority to cite, but the free encyclopedia does certainly help to keep topics current.

"Such orbits cannot have been created by gravitational scattering by the gas giants (in particular Neptune). Instead, a number of explanations have been put forward, including the encounter with a passing star or a distant planet-sized object."

Certainly. That explanation is reasonable, but does not in any way suggest that these objects formed outside the Solar System.

[dougettinger]

The Wiki explanation is then only referring to an "encounter" with the Oort cloud by a passing star or distant planet and not the exchange of any bodies. One fact is hard to believe is that all ejected bodies do not always remain in highly elliptical orbits and eventually collide with the Sun or a planet or be perturbed into other elliptical orbits with perihelia much closer than 1 ly radius. But then my computer modeling experience is very minimal. Thanks for all your time.

Doug