Cork Astronomy Club was honoured to welcome Dr Ann-Marie Madigan, Assistant Professor of Astrophysics at University of Colorado, Boulder. There’s something odd going on in our solar system, and presence of a new planet (‘planet 9′) or a black hole have been proposed to account for it, but Dr Madigan has other ideas.
Prof Madigan’s favoured explanation is a new Kuiper belt, further out than the actual Kuiper belt, and containing about 10 Earth masses of material. If found, will it be called the Madigan Belt? You heard it here first.
Dr Madigan explained: While the planets move on nearly-circular orbits in a disk, the icy bodies beyond Neptune appear to cluster together in a highly-inclined and eccentric structure. Astronomers have invoked the presence of a new planet (‘planet 9′) or even a black hole in explanation!
In her talk she showed that these theories are unnecessary. In analogy with spiral arms and bars in galaxies, the collective gravity of individually small but collectively massive bodies can create such structure in the outer solar system. This explanation predicts that there is a (highly-inclined) disk of minor planets, more massive than the Kuiper Belt, awaiting discovery at the edge of our solar system.
This lecture was held via Zoom.