0 Members and 1 Guest are viewing this topic.
"Looks like the outer solar system, with late heavy bombardment, would have come together nicely if there was another Neptune out there to begin with."
"So we let debris drag bring Jupiter and Saturn into resonance with a little bit of orbital migration, scatter Uranus and Neptune out (and use the debris to recircularise) and we get the details more or less right if we let a second Neptune have been there and been ejected, either to infinity or outer Oort cloud."
"Undoubtedly, something massive knocked the hell out of the belt, the question is whether it's there now."[
This theory has been around for quite a while but, as Ian said, thus far there is no evidence whatsoever for its existence.Taken from http://en.wikipedia.org/wiki/Oort_cloud...physicist Richard A. Muller and others have postulated that the Sun has a heretofore undetected companion (brown dwarf or gaseous giant planet) in an elliptical orbit beyond the Oort cloud. This object, known as Nemesis, is theorized to pass through a portion of the Oort cloud approximately every 26 million years, bombarding the inner solar system with comets. Although the theory has many proponents, no direct proof of the existence of Nemesis has been found. Furthermore, many argue that a companion star at such a great distance could not have a stable orbit, as it would probably be ejected by perturbations from other stars.
Please bear in mind that in these pages you are presenting to a general public and your writings are more suited for professional astronomy pages and in fact were probably copied verbatim from them. When faced with a heavy load of acronyms and detail most readers will turn off and ignore your input.
You seem to be quite knowledgable in the area so I will turn the question back towards you.I am quite interested in the size versus numbers statistics of objects growing in condensing clouds expecting objects all the way from groups of molecules right up to 100 solar mass stars to appear in the statistics. The fact that the clouds eventually become mostly transparent implies upper limits to the density of very small particles but I see no reason why the numbers should not continue to increase as size deceases up to some quite small size limit.In the past I have seen people arguing that it stops with small star or Brown dwarf sized objects but I was always suspicious of their arguments. Perhaps you can shed some light on this?