https://soylentnews.org/article.pl?sid=19/01/22/0749230&from=rss
https://arxiv.org/abs/1804.06859
https://soylentnews.org/article.pl?sid=18/06/05/125246
The strange orbits of some objects in the farthest reaches of our solar system, hypothesised by some astronomers to be shaped by an unknown ninth planet, can instead be explained by the combined gravitational force of small objects orbiting the Sun beyond Neptune, say researchers.
The alternative explanation to the so-called 'Planet Nine' hypothesis, put forward by researchers at the University of Cambridge and the American University of Beirut, proposes a disc made up of small icy bodies with a combined mass as much as ten times that of Earth. When combined with a simplified model of the solar system, the gravitational forces of the hypothesised disc* can account for the unusual orbital architecture exhibited by some objects at the outer reaches of the solar system.
[...] "The Planet Nine hypothesis is a fascinating one, but if the hypothesised ninth planet exists, it has so far avoided detection," said co-author Antranik Sefilian, a PhD student in Cambridge's Department of Applied Mathematics and Theoretical Physics. "We wanted to see whether there could be another, less dramatic and perhaps more natural, cause for the unusual orbits we see in some TNOs. We thought, rather than allowing for a ninth planet, and then worry about its formation and unusual orbit, why not simply account for the gravity of small objects constituting a disc beyond the orbit of Neptune and see what it does for us?"
[...] Earlier attempts to estimate the total mass of objects beyond Neptune have only added up to around one-tenth the mass of Earth. However, in order for the TNOs to have the observed orbits and for there to be no Planet Nine, the model put forward by Sefilian and Touma requires the combined mass of the Kuiper Belt to be between a few to ten times the mass of Earth. [...] "It's also possible that both things could be true -- there could be a massive disc and a ninth planet. With the discovery of each new TNO, we gather more evidence that might help explain their behaviour."
*cue the flat earthers claiming.. SEE THERE IS A DISC!
I think Terry Pratchett would want to know if it's on the back of four elephants who stand upon a giant turtle called The Great A'Tuin
https://wiki.lspace.org/mediawiki/Great_A'Tuin