Planet 9 and a 3 million years ago Stellar Flyby:

[beecee]

https://phys.org/news/2019-02-exiled-planet-linked-stellar-flyby.html

Exiled planet linked to stellar flyby three million years ago

February 28, 2019, University of California - Berkeley

Some of the peculiar aspects of our solar system—an enveloping cloud of comets, dwarf planets in weird orbits and, if it truly exists, a possible Planet Nine far from the sun—have been linked to the close approach of another star in our system's infancy flung things helter-skelter.

But are stellar flybys really capable of knocking planets, comets and asteroids askew, reshaping entire planetary systems?

UC Berkeley and Stanford University astronomers think they have now found a smoking gun.

A planet orbiting a young binary star may have been perturbed by another pair of stars that skated too close to the system between 2 and 3 million years ago, soon after the planet formed from a swirling disk of dust and gas.

If confirmed, this bolsters arguments that close stellar misses help sculpt planetary systems and may determine whether or not they harbor planets with stable orbits.

Read more at: https://phys.org/news/2019-02-exiled-planet-linked-stellar-flyby.html#jCp

 

the paper:

https://iopscience.iop.org/article/10.3847/1538-3881/ab0109/meta

A Near-coplanar Stellar Flyby of the Planet Host Star HD 106906

Abstract:

We present an investigation into the kinematics of HD 106906 using the newly released GaiaDR2 catalog to search for close encounters with other members of the Scorpius–Centaurus (Sco–Cen) association. HD 106906 is an eccentric spectroscopic binary that hosts both a large asymmetric debris disk extending out to at least 500 au and a directly imaged planetary-mass companion at a projected separation of 738 au. The cause of the asymmetry in the debris disk and the unusually wide separation of the planet is not currently known. Using a combination of Gaia DR2 astrometry and ground-based radial velocities, we explore the hypothesis that a close encounter with another cluster member within the last 15 Myr is responsible for the present configuration of the system. Out of 461 stars analyzed, we identified two candidate perturbers that had a median closest approach distance within 1 pc of HD 106906: HIP 59716 at  pc ( Myr) and HIP 59721 at  pc ( Myr), with the two stars likely forming a wide physical binary. The trajectories of both stars relative to HD 106906 are almost coplanar with the inner disk (Δθ = 54 ± 1.7 and ). These two stars are the best candidates of the currently known members of Sco–Cen for having a dynamically important close encounter with HD 106906, which may have stabilized the orbit of HD 106906 b in the scenario where the planet formed in the inner system and attained high eccentricity by interaction with the central binary.

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So we have mathematical evidence that the hypothesised Planet X or 9 if you prefer, [being rather old school, Pluto still holds that spot imho] may actually exist somewhere. It may also explain some of the anomalies of orbits of comets and KBO's from past reports. From memory of past hypothesised accounts of Planet x, it would obviously have a highly elongated orbit, being taking around 20,000 Earth years to make one orbit. Just as obviously if it is near its Aphelion, this can explain why it hasn't yet been visually detected.

The data and mathematics also could be explanations of other possibilities also.

While we are able to determine the presence of extrasolar planets by the gravitational tugs they have on their parent Star, is this methodology possible within our own system? My thoughts, probably not, simply because we are too  close and actually part of that system. Any thoughts?

Edited February 28, 2019 by beecee