Andrew McKellar was born in 1910 in Vancouver, British Columbia. In 1930, he received his bachelor’s degree from the University of British Columbia in Vancouver, and then enrolled at the University of California in Berkeley where he obtained his master’s degree in 1932 and his doctoral degree in 1933. He specialized in molecular spectroscopy; that is, in the detection and analysis of molecular structure.

In 1933, he became a postdoctoral researcher at the Massachusetts Institute of Technology in Cambridge. It was there that he made his first forays into astronomy by studying the Sun. In 1935, he accepted a position at the Dominion Astrophysical Observatory in Victoria, British Columbia. He began measuring the orbits of binary stars and pursued his own research into molecular spectroscopy.

World War II erupted in 1939 and McKellar became a research officer for the Royal Canadian Navy. He attained the rank of lieutenant commander, all the while pursuing his astronomy work and publishing several significant scientific articles. In 1940, he began using spectroscopy to determine the composition of comets and demonstrated that solar rays modify their sp Read More
Andrew McKellar was born in 1910 in Vancouver, British Columbia. In 1930, he received his bachelor’s degree from the University of British Columbia in Vancouver, and then enrolled at the University of California in Berkeley where he obtained his master’s degree in 1932 and his doctoral degree in 1933. He specialized in molecular spectroscopy; that is, in the detection and analysis of molecular structure.

In 1933, he became a postdoctoral researcher at the Massachusetts Institute of Technology in Cambridge. It was there that he made his first forays into astronomy by studying the Sun. In 1935, he accepted a position at the Dominion Astrophysical Observatory in Victoria, British Columbia. He began measuring the orbits of binary stars and pursued his own research into molecular spectroscopy.

World War II erupted in 1939 and McKellar became a research officer for the Royal Canadian Navy. He attained the rank of lieutenant commander, all the while pursuing his astronomy work and publishing several significant scientific articles. In 1940, he began using spectroscopy to determine the composition of comets and demonstrated that solar rays modify their spectra.

Also in 1940, he was the first to detect the presence of matter in interstellar space when he identified the spectrum of the organic compounds cyanogen (“CN”) and methyne (“CH”). In 1941, he determined the temperature of the cyanogen molecules and deduced that the interstellar medium in which they are found is very cold, approximately -271 °C.

Nearly 25 years later, in 1964, Arno Penzias and Robert Wilson confirmed McKellar’s discovery when they detected microwave light coming from all regions of the sky corresponding to a temperature of -271 °C. This emanation is known as cosmic background radiation: the light emitted several hundred thousand years after the birth of the Universe when the first atoms were created. In 1978, with McKellar having passed away almost twenty years earlier, the Nobel Prize in Physics was awarded to Penzias and Wilson for their part in the discovery that launched the Big Bang hypothesis to the forefront of cosmological theories.

When World War II ended in 1945, McKellar reclaimed his position as researcher at the Dominion Astrophysical Observatory in Victoria and remained there until his death in 1960.
The Dominion Astrophysical Observatory in Victoria.

In 1948, he was the first to provide proof of the existence of the carbon-nitrogen cycle (“CN cycle”) within cold carbon stars. The CN cycle, which had been predicted 10 years earlier, is a chain of thermonuclear reactions in which carbon and nitrogen combine to release enormous amounts of energy. According to the theory, it is this energy that sustains cold carbon stars.

During the 1950’s, McKellar became increasingly interested in giant cold stars (those with surface temperatures as low as 2,000° C) and broadened our knowledge about their size and chemical composition. Among other contributions, he demonstrated that large turbulent movements could agitate their atmospheres.

Succumbing to an incurable disease, he died in 1960 in Victoria, British Columbia, at the young age of 50. He had completed a full day of work at the observatory just four days before he passed away.

McKellar received many awards for his work in astronomy, including being elected as a member of the Royal Society of Canada. In 1962, the Dominion Astrophysical Observatory in Victoria named their 1.2-metre telescope in his honour. The telescope is used to measure the speed of stars and to determine their chemical compositions.

© 2006 An original idea and a realization of the ASTROLab of Mont-Mégantic National Park

Black and white photo of Andrew McKellar

Andrew McKellar (1910-1960).

Royal Astronomical Society of Canada

© Royal Astronomical Society of Canada


black and white photo of the Dominion Astrophysical Observatory in Victoria

The Dominion Astrophysical Observatory in Victoria.

National Research Council of Canada
Herzberg Institute of Astrophysics/Dominion Astrophysical Observatory

© National Research Council of Canada


Arthur Edwin Covington was born in 1913 in Regina, Saskatchewan. In 1938, he received his bachelor’s degree from the University of British Columbia in Vancouver, and obtained his master’s degree from the same institution in 1940. That same year, he enrolled at the University of California in Berkeley where, two years later in 1942, he received his doctoral degree in nuclear physics. At that point, he moved to Ottawa, Ontario, and participated in the war effort by helping develop new radar systems at the National Research Council of Canada.

After the war, Covington proposed a research project that would convert surplus radar equipment into instruments that could study cosmic radiation. His proposal was accepted in 1946 and he began constructing the first Canadian radio telescope. Once the equipment had been calibrated, he decided to measure the radiation emanating from the Sun, or more specifically, it’s “radio flux”: the variations in its energy output at radio wavelengths.

He began collecting data in July of 1946 and quickly realized that the flux changed from day to day. Unable to determine whether these daily variations were r Read More
Arthur Edwin Covington was born in 1913 in Regina, Saskatchewan. In 1938, he received his bachelor’s degree from the University of British Columbia in Vancouver, and obtained his master’s degree from the same institution in 1940. That same year, he enrolled at the University of California in Berkeley where, two years later in 1942, he received his doctoral degree in nuclear physics. At that point, he moved to Ottawa, Ontario, and participated in the war effort by helping develop new radar systems at the National Research Council of Canada.

After the war, Covington proposed a research project that would convert surplus radar equipment into instruments that could study cosmic radiation. His proposal was accepted in 1946 and he began constructing the first Canadian radio telescope. Once the equipment had been calibrated, he decided to measure the radiation emanating from the Sun, or more specifically, it’s “radio flux”: the variations in its energy output at radio wavelengths.

He began collecting data in July of 1946 and quickly realized that the flux changed from day to day. Unable to determine whether these daily variations were related to problems with the instruments or to the presence of dark spots (“sunspots”) found on the Sun’s surface, he decided to use a partial solar eclipse on November 23, 1946, to his advantage: he would monitor any variations in the radio flux as sunspots became covered by the Moon.

Record of the solar activityMuch to his surprise, he determined that the dimmer regions of the Sun – those marked by sunspots – emit much stronger radiation than the more luminous unmarked areas. He thus provided the first direct evidence that sunspots are associated with radiation “hot spots”.

Encouraged by this discovery, Covington began collecting daily data on the Sun’s radio flux in 1947, and succeeded in demonstrating that the number of sunspots is related to the Sun’s radiation flux. He collected data on a continuous basis from that point forward and his measurements were used around the world.

The Algonquin Radio Observatory.In 1951, he constructed a device that would detect the radiation emitted by specific regions on the Sun’s surface. He thus managed to measure the brilliance of the Sun’s corona (the uppermost level of the Sun’s atmosphere) and the temperature of the regions above sunspots (about 1,500,000 °C). His work would greatly contribute to our understanding of the underlying mechanisms that create sunspots.

Covington succeeded in demonstrating that the intensity of solar radiation is related to the magnetic activity of the Sun, which has crucial implications for numerous human activities, such as communications systems, power lines, climate predictions, agriculture, fishing, space exploration, manmade satellites, geophysics, etc.

In 1959, the Algonquin Radio Observatory was established in Ontario and Covington became its director. He took his retirement in 1978 and died in 2001 in Kingston, Ontario, at 88 years old. One of the buildings at the Herzberg Institute of Astrophysics in Penticton was named in his honour in 2003.

© 2006 An original idea and a realization of the ASTROLab of Mont-Mégantic National Park

Black and white photo of Arthur Edwin Covington

Arthur Edwin Covington (1913-2001).

Portrait of Arthur E. Covington held in the Riche-Covington Collection
W.D. Jordan Special Collections and Music Library/Queen's University at Kingston

© W.D. Jordan Special Collections and Music Library/Queen's University at Kingston


Graph depicting Solar Activity

Record of the solar activity during the partial solar eclipse of November 23, 1946.

National Research Council of Canada

© National Research Council of Canada


Black and white photo of the Algonquin Radio Observatory

The Algonquin Radio Observatory.

National Research Council of Canada

© National Research Council of Canada


Anne Barbara Underhill was born in 1920 in Vancouver, British Columbia. She obtained her bachelor’s degree in 1942 and her master’s degree in 1944 from the University of British Columbia in Vancouver. In 1948, she received a doctoral degree from the University of Chicago. Her thesis supervisor was Subramanyan Chandrasekhar, a leading authority in the field of black holes and recipient of the 1983 Nobel Prize in Physics.

In 1948, Underhill completed postdoctoral work at the Copenhagen Observatory in Denmark, and then joined the Dominion Astrophysical Observatory in Victoria, British Columbia, where she stayed until 1962.

Underhill specialized in the study of “early-type stars” or “OB stars”; that is, very hot blue stars. Newly discovered and poorly understood at the time, these stars were surrounded by very thick atmospheres. Underhill collected a lot of data on OB stars at Victoria but quickly realized that no existing mathematical model could interpret her data.

Not one to give up, Underhill took it upon herself to develop and perfect the mathematical equations required to model the atmospheres of OB stars. She Read More
Anne Barbara Underhill was born in 1920 in Vancouver, British Columbia. She obtained her bachelor’s degree in 1942 and her master’s degree in 1944 from the University of British Columbia in Vancouver. In 1948, she received a doctoral degree from the University of Chicago. Her thesis supervisor was Subramanyan Chandrasekhar, a leading authority in the field of black holes and recipient of the 1983 Nobel Prize in Physics.

In 1948, Underhill completed postdoctoral work at the Copenhagen Observatory in Denmark, and then joined the Dominion Astrophysical Observatory in Victoria, British Columbia, where she stayed until 1962.

Underhill specialized in the study of “early-type stars” or “OB stars”; that is, very hot blue stars. Newly discovered and poorly understood at the time, these stars were surrounded by very thick atmospheres. Underhill collected a lot of data on OB stars at Victoria but quickly realized that no existing mathematical model could interpret her data.

Not one to give up, Underhill took it upon herself to develop and perfect the mathematical equations required to model the atmospheres of OB stars. She began in the 1950’s, an era in which the only available computers were mechanical devices that had to be manually operated; it was an arduous task due to the enormous amount of time required to complete each calculation.

In 1962, Underhill became a professor of stellar astrophysics at Utrecht University in the Netherlands where she pursued her work on OB stars. In 1966, she wrote The Early Type Stars, a book that quickly became a standard reference for OB stars.

Nebula M1-67In 1970, Underhill became the director of the new optical astronomy laboratory at the NASA Goddard Space Flight Center at Greenbelt, Maryland. She contributed to the development of the International Ultraviolet Explorer Satellite until 1977, at which point she returned to her work on OB stars.

It was in the 1970’s that Underhill became convinced that Wolf-Rayet type stars are young, not old (an idea that we now know to be incorrect), and she retained this conviction for the rest of her life. Wolf-Rayet stars release colossal quantities of matter into space.

She retired in 1985 and returned to Canada as Professor Emeritus at the University of British Columbia in Victoria. She died in Vancouver at the age of 83. She received numerous awards for her work in astronomy and was elected as a member of the Royal Society of Canada.

© 2006 An original idea and a realization of the ASTROLab of Mont-Mégantic National Park

Black and white photo of Anne Barbara Underhill

Anne Barbara Underhill (1920-2003).

Astronomy and Geophysics, vol. 44, no. 6, 6.35

© Astronomy and Geophysics, vol. 44, no. 6, 6.35


Colour photo of Nebula M1-67

Nebula M1-67 surrounding the Wolf-Rayet star WR124.

Yves Grosdidier, Anthony Moffat, Gilles Joncas, Agnes Acker and NASA
University of Montreal and Strasbourg Observatory, University of Montreal, Gilles Joncas, Agnes Acker and NASA

© NASA


Learning Objectives

The learner will:
  • identify recent contributions, including Canada’s, to the development of space exploration technologies;
  • describe in detail the function of Canadian technologies involved in exploration of space;
  • draw a solar system with all its components;
  • establish the link between atoms and light using different instruments.

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