KBO binaries: are they really primordial ?

摘要: Given the large orbital separation and high satellite-to-primary mass ratio of all known Kuiper Belt Object (KBO) binaries, it is important to reassess their stability as bound pairs with respect several disruptive mechanisms. Besides classical shattering dispersing secondary due a high-velocity impact, we considered possibility that kicked off its orbit by direct collision small impactor, or gravitationally perturbed close approach somewhat larger TNO. Depending on values for size/mass/separation binaries used, 2 3 8 can be dispersed in timescale shorter than age solar system current rarefied environment. A contemporary formation scenario could explain why still observe these but no convincing mechanism has been proposed date. The primordial scenarios, which seem only viable ones, must revised increase efficiency order account this dispersal rate. Objects like large-separatioKBO binary n2001 QW$_{322}$ have initially an magnitude more numerous. If KBO are indeed primordial, then show depletion belt cannot result from collisional grinding, rather dynamical ejection.