Canada lost a well known member of its first generation of radio astronomers on April 25, 2002 when Lorne Doherty died after a long illness.
Lorne was born in Montreal in 1922. He received Bachelor of Electrical Engineering degree at McGill University in 1944, a degree made possible by scholarships awarded for an exceptional academic record. His thesis work for a Ph.D. in Electrical Engineering (Cornell University, 1952) was on radio wave propagation. He continued this work during the 1950’s after joining the National Research Council, Ottawa, in 1952 and became quite well known in this field for his experimental work on the tropospheric propagation of microwave signals. This included below-the-horizon transmission of microwaves from Ottawa to Toronto, and from Ottawa to Dorval airport, Montreal, as well as, on the Great Lakes, measurements of the transmission of microwaves over water.
By the early 1960’s, Lorne’s interests were drawn to the promising and rapidly developing science of radio astronomy. At this time NRC was starting to build a radio observatory in Algonquin Park to the north of Ottawa, the Algonquin Radio Observatory. Lorne became involved at an early stage. He was a leading member of a small team that got the first telescope at the observatory operating. This was a 33 ft diameter reflector telescope which served as a test-bed for the 150 ft telescope still being constructed. When the 150 ft telescope was completed (c. 1966) it provided a record collecting area at the time for short cm wavelengths. To exploit this feature, Lorne undertook a major observing program in collaboration with NRC colleague John MacLeod: measurement of the 2.8 cm flux of the entire 3CR catalog of radio sources. These observations significantly extended the spectral index information on these source to higher frequencies. Lorne and John also collaborated on galactic radio astronomy, mapping at 2.8 cm such source as: W48, W51, Orion A, and the structurally complex NGC 2024.
Because of his engineering background Lorne was able to contribute substantially to the instrumentation of the observatory. He was chairman of the observatory receiver committee for many years, and for decades a persistent advocate of outfitting the observatory telescopes with the best possible low-noise receivers. Lorne was also the principle champion for the building of a telescope polarizer. In later years, with the planned refurbishing of the telescope he worked on means of improving the telescope pointing.
Lorne was also a key organizer in bringing about a very fruitful collaboration within the Herzberg Institute of Astrophysics: that between the (then) Astronomy Section and the Spectroscopy Section. This led directly at ARO to the first detection anywhere of a number of cm wavelength molecular lines.
Lorne will be especially remembered as an always calm and rational voice in discussions and meeting of all kinds and as one who took painstaking care in everything he undertook. These qualities served him well when he was asked to represent Canadian radio astronomy as a member of the Canadian Frequency Allocation Committee. A major part of this job was the defence of radio astronomy frequencies at international allocation meetings.
Lorne officially retired from the Herzberg Institute of Astrophysics, NRC, in 1986, and set about fulfilling two long-time ambitions: with his wife Harriet he spent much of one year touring the wine regions of France following which he enrolled in a university economics course. He completed his NRC career by returning to frequency allocation work for about two years.
Lorne is survived by Harriet, by six children and by eleven grandchildren one of whom (so far) is studying astrophysics.
Tom Legg
June, 2002