Distinguished Research Professor Emeritus Gordon G. Shepherd will deliver the fall term lecture for the Association of Retired Faculty and Librarians (ARFL) at York University on Nov. 1.
Shepherd, of the Lassonde School of Engineering’s Department of Earth & Space Science & Engineering, presents the talk “Earth’s Aurora and Airglow as Seen from Below and Above.” The presentation will take place in the Harry Crowe Room (109 Atkinson College) from 1 to 3 p.m. and is open to all.
The talk explores how the sun totally controls the environment in which we live, through the light it emits (ultraviolet, visible and infrared), through ionized particles (electrons and ions) and through its magnetic field that creates the Earth’s magnetosphere. Of the incredible influence of all this, only the visible light reaches the Earth’s surface; most of the rest is absorbed in the high atmosphere, 80 to 300 kilometres above the Earth’s surface.
The intent of this presentation is to allow attendees to see the consequences of that energy deposition. The most obvious visual manifestation of the energy deposition in the upper atmosphere, accessible to viewers on the ground, is the aurora borealis (or australis), and this is easily seen if you are in the right place at the right time. But equally interesting is the unseen airglow, a high-altitude layer of sub-visual light covering the whole surface of the globe, for which instruments employed on the ground, or from space, make it possible to see anywhere at any time.
The presentation will demonstrate how instruments can be used to make the airglow visible from rocket and satellite platforms flown in space by York University scientists, among others. The largely visual presentation will consist mainly of images of the sun, the aurora and the airglow acquired with space instrumentation; it will summarize the current understanding and significance of these phenomena.
Shepherd is a Fellow of the Royal Society of Canada and the American Geophysical Union. He received the Canada Space Agency’s John H. Chapman Award of Excellence in 2003, the Canadian Aeronautics & Space Institute Alouette Award in 2004, the SCOSTEP Distinguished Scientist Award in 2014 and the COSPAR William Nordberg Medal in 2016.