A personal tribute to Michael Gadsden

I first met Michael Gadsden in the late 1970s when he visited our Upper Atmospheric Group at Southampton University, UK. At that time I was a new graduate student studying for my Ph.D. under Pamela Rothwell. Mike (as I was later privileged to call him) was interested in developing a collaborative program to study polarization in noctilucent clouds (NLC) using our low-light video cameras. Of course at that time I had never even heard of noctilucent clouds but what an impression he made on us all! Within a couple of months I found myself heading north for Scotland, with my car packed full of video gear, eager to learn all about these fascinating night shining clouds that only occur during the summer months at higher latitudes. True to his nature, Mike gave me the “royal tour” of the ancient city of Aberdeen and its famous university, introducing me to the faculty in the Department of Natural Philosophy as a “heathen from the south” (you have to say it with a Scottish accent) who had “come north for the summer to gain a decent education!” We set up our cameras at the majestic Cromwell Tower Observatory, located in Kings College in the oldest part of the university (circa 1400 AD). Mike had recently refurbished this abandoned observatory and after several weeks of tutoring me while waiting for the Scottish skies to clear, we were eventually rewarded with a wonderful NLC display. It was a most impressive event that lit up the northern sky late at night, with many beautiful iridescent blue-white waves illuminated within the twilight arch. I savored this eerie yet tranquil time, and as the display grew in brightness, it was soon accompanied by a chorus of birds singing as they were tricked by this “false dawn”. I was firmly hooked! Moreover, we gained our first data on circular polarization in NLC on this night and Mike swiftly prepared a letter for publication in Nature [Gadsden, Rothwell, Taylor, 1979. Nature 278]. Therein began a wonderful relation with Mike, first as a mentor and later as a colleague and dear friend