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Astronomers Spot Most Distant Object In the Solar System (sciencemag.org)
sciencehabit writes: Astronomers have found the most distant known object in our solar system, three times farther away than Pluto. The dwarf planet, which has been designated v774104, is between 500 and 1000 kilometers across. It will take another year before scientists pin down its orbit, but it could end up joining an emerging class of extreme solar system objects whose strange orbits point to the hypothetical influence of rogue planets or nearby stars.
In other planetary science news, UCLA professor Jean-Luc Margot has proposed a new definition of the term "planet" which would allow for the inclusion of exoplanets. His metric is laid out in an academic paper available at the arXiv.
In the words of Wikipedia, "Citation needed". The planetary scientists at the IAU meeting had been by and large pursuing a definition involving a body reaching gravitational equilibrium. They've also been leading the charge to get it overturned. There are numerous published papers by planetary scientists who continue to refer to large KBOs and the like as planets. The New Horizons team is particularly notable in continued references to them as planets.
The vote passed via a non-randomly-selected 4% of the IAU's membership who were - as previously mentioned - overwhelmingly not planetary scientists. Letting people who study stars (by the way, a "dwarf star" is still a "star") decide what a planet is is just plain stupid - it's not their field of expertise. The first draft proposal indeed went with the planetary scientists' version - hydrostatic equilibrium being the criteria, and was confirmed on the 18th, with intent to vote on the 24th. Many people left the IAU meeting thinking that this was the version that was going to be voted on, and since they supported either having it or no definition at all, they didn't need to be there. The proposal was changed however on the 22nd. Due to dischord among the IAU members there were "secret" negotiations held on the proposal on the evening of the 23rd, and it looked increasingly unlikely that anything was going to be agreed upon. But then they came out with the current version on the 24th - after most of the membership had left - and had it voted on during the same day, when most of the people remaining were the ones who had been fighting against the planetary scientists' equilibrium definition. They furthermore reverted the standard rules which only allow people in a specific field to vote on matters related to their field, declaring the definition of planet a matter applicable to the whole union, so that everyone, not just planetary scientists, could vote.
There are not little complaints about "the exact wording" - do I really need to go into a breakdown of all of the arguments against it?
The yellowcake is a lie.
Mars does not gravitationally dominate its neighborhood and force things into resonance with it. The vast majority of asteroids are locked into resonances with Jupiter, not Mars. There's only about 1500 known asteroids, the Polana group, which are locked into a 2:1 resonance with Mars (Mars also has 4 trojans which do not appear related to each other).
The Stern-Levison parameter is based around the principle of scattering small bodies, bodies far smaller than the parent, which can be scattered on a single pass at distance b to an angle greater than or equal to a given value. Pluto is a "small body" compared to Neptune, but not so compared to Mars. And Mars's Stern-Levison parameter is, again, far less than Neptune's.
The claim that "a value of over 900 for Mars is more than enough to clear out other bodies" is false even if we ignore this troublesome "small body" aspect. Again, read the Stern-Levison paper. The value of 900 for Mars comes from assuming a scattering angle of one radian from its approach angle, which hardly means ejection or single-pass domination. It assumes 12 billion years for the age, several times older than the solar system. It relies on the "small bodies" having high eccentricities, which would probably not be the case in a gas-giant-less solar system - the lower the eccentricity, the far weaker the scattering potential. And of course, they assume actual small bodies - typical asteroid sizes.
Interestingly enough, I would have been happy with the classification actually laid forth in Stern-Levison (2002). They proposed a size/composition matrix similar to that of stars, with all objects large enough to be in hydrostatic equilibrium included. The mass would be grouped into "subdwarf" (Ceres, Pluto, Charon, etc), "dwarf" (Mercury, Venus, Earth, Mars), "subgiant" (Uranus, Neptune, Saturn), "giant" (Jupiter), and "supergiant" categories, while the composition grouped into "rock" (terrestrial planets, asteroids), "ice" (KBOs, uranus, neptune), and "hydrogen" (saturn, jupiter). So for example Jupiter would be a "hydrogen giant planet". Pluto would be a "rocky subdwarf planet". Titan would be a "icy subdwarf satellite". Etc.
The yellowcake is a lie.