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"Shooting Stars and Hairy Stars"

A Scientific Meeting of the Astronomy Unit

Marking the 70th Birthday and Retirement of Prof. Iwan Williams, Former Dean of the Faculties of Informatics, and Engineering and Mathematical Sciences


2nd December 2009


All talks will be held in the Arts Lecture Theatre


The aim of the meeting is to provide an overview of the current state of knowledge regarding the smaller members of the Solar System, which, over the working life of Iwan Williams has increased exponentially. One of the most successful of the space missions has been Cassini, which is orbiting Saturn. It has given additional insight into many aspects of the Saturnian System, but in particular it has cast new light on our understanding of the ring system and of inter-relationships between the rings and the small moons that also orbit in the same locality. An other significant development over the last 20 years has been the discovery of a family of objects orbiting beyond Neptune and popularly known as the Edgeworth-Kuiper belt. This belt may be the source of some comets (Hairy stars) and also some of the Moons of the outer planets. our understand of comets has also gone through some changes, from initially being thought of as a loose agglomeration of small dust grains (the flying sand-bank model) to the dirty snowball model which became modified to the snowy dirt-ball model and currently some believe that comets could be an agglomeration of distinct large pieces, the rubble-pile model. Shooting Stars (properly called meteors and caused by particles smaller than a frozen pea burning up in the earth's atmosphere) originate from comets and can give us an insight into the true nature of comets. Finally, many planets have now been discovered about other stars, with very different set ups from our solar system and the stability of such systems over a long time interval is interesting in its own right, but also as a way of deepening our understanding our own Solar System.


2:25pm          Prof. David Burgess (QMUL)


2:30pm          Prof. Carl Murray (QMUL)

                        "The Twists and Turns of Saturn's F Ring"

3:15pm          Dr. Richard Donnison (QMUL)

                        "The stability of moons and planets"

3:40pm          Break (20 mins)

4:00pm          Prof. Alan Fitzsimmons (QUB)

                        "At the Edge of Darkness: Today's Kuiper-belt"

4:45pm          Prof. Iwan Williams (QMUL)

                        "From Flying Sand-Banks to Rubble Piles"

5:30pm          End of Meeting