- About PSI
The idea of Solar system being a finely tuned clock with all the planets and small bodies in their permanent place has been long abandoned. Our current understanding is that there is a constant exchange of mass between the various small body regions, where objects are steadily leaking due to the gravitational perturbations from the two largest reservoirs - the main belt and the Kuiper belt, creating transient populations. I will focus my talk on the specifics of two transient populations -- the Near-Earth Objects (NEOs), which have been the main focus of my studies for several years now, and the Centaurs, which I intend to investigate in the near future.
The term 'NEO' covers asteroids or comets orbiting the Sun with perihelion distance q < 1.3 AU, where most of these objects have been transferred into their current orbits from the main belt. NEOs may pose a threat to Earth's biosphere, because many of their orbits bring them close to Earth and they may eventually impact our planet. However, this also makes them the easiest accessible spacecraft targets for both commercial (e.g. asteroid mining) and scientific purposes of all the objects in the Solar system.
Centaurs reside on unstable orbits between Jupiter and Neptune, and are regarded as transition objects between their source in the Kuiper Belt (KB) and Jupiter family comets (JFCs). As such, they offer an intriguing insight into the small sizes of the Kupier belt population, with their size-frequency distribution being mostly unaltered (unlike the JFCs) by substantial mass loss. However, some of them show comet-like activity even far beyond the orbit of Jupiter, the source of which is not yet fully understood, and could point out on the delivery of water and primitive organic material from the Kuiper Belt into the inner Solar system.