No Really Big Worlds Beyond The Kuiper Belt? Options

[ljk4-1]

No Kuiper Belt Jupiters; No Nemesis

Astronomers have long wondered whether the solar system might have an
unseen giant planet far out in the darkness beyond Pluto and the Kuiper
Belt. If so, it must be very far out indeed.

Nadia Zakamska and Scott Tremaine have set new limits on the existence
of any such massive object.... Earlier this year, Varun Bhalerao and M. N.
Vahia showed that no red-dwarf companion of the Sun (a so-called "Nemesis"
object) can exist within 25,000 astronomical units....

http://SkyandTelescope.com/news/article_1609_1.asp

[Guest_Richard Trigaux_*]

If we read the paper, we find that the accuracy of their work is the detection of 1 Jupiter mass at 200 AU (30 billion kms, 5 times the distance of Pluton). This rules out star-sized bodies at short distance, but still allows for many surprises, such as Jupiter-sized objets at a great distance. If we assume that the effect of the Sun follows a 1/R2 law, at 0.1 light year we could still have 1000 Jupiter mass, or the mass of the Sun. At less than 0.2 light years a small black hole can still hide into the error box.

More realistically we can say:

-This study does not rule out Jupiter sized bodies in the far solar system, especially if they are many (in a belt) or a cloud of gaz in orbit or close vicinity.

-we are still far from detecting the effect of neighbouring stars. A 1000 more resolution would be necessary to detect the effect of Proxima centauri.


This study brings matter for the study of the Pioneer anomaly, or for the study of the anomalies in the cosmic background radiation. (there is an assymettry in this background, which seems related to the solar sytem)

[blobrana]

More realistically we can say:

-This study does not rule out Jupiter sized bodies in the far solar system.

Indeed,
but I wonder how stable those very distant orbits would be, (in the long term), given that passing stars come quite close by every few million years.

I imagine that in a time scale of a few hundred million years, most would be flung out of our system
(er, on the other hand, the sun may acquires new ones)...