Twinkling of the Stars
Date: Wednesday, 3 September, 2014
Time: 8:00 PM - 9:30 PM
Venue: Kerr Grant Theatre
Location: 2nd Floor, Physics Building, University of Adelaide North Tce Campus
Presented by Dr Laurence Campbell - School of Chemical and Physical Sciences, Flinders University
(Please note: This lecture will be at a higher technical level and not aimed at the general public)
In the 13th century Roger Bacon wrote “Hence we see nothing so frequently of whose cause we know less: it is the scintillation of the stars.” In the following centuries the cause has been a subject of argument, at times acrimonious, among scientists. Even today, the essential characteristics of the phenomenon are not widely known, let alone understood. Yet many of these characteristics can be observed with simple equipment and techniques. I will describe the historical development of the observations and understanding of twinkling, including the major controversies. The story is intertwined with the (at times more acrimonious) development of the theories of light, as well as general progress in astronomy, physics and technology. I will then address the observations that can now be made of twinkling with readily available equipment, ranging from your eyes and one finger to digital cameras. These will include observations made at recent ASSA observation sessions, allowing investigation of the relationship between twinkling and “seeing”.
Laurence Campbell completed a PhD in 1991 at the University of Adelaide on “Stellar Scintillation and its use in Atmospheric Measurements”. Since then he has worked at the University of Adelaide on analysis of meteor observations and (primarily) at Flinders University on numerical simulation of electron-impact processes in planetary and cometary atmospheres. He has maintained an interest in his PhD subject, particularly as an example of the role of physics in understanding the world around us.