Banner image: the Canada-France-Hawaii Telescope at Maunakea, Hawai’i, operational since 1979. The mirror and a number of the instruments were built at DAO

The People

Dr. Gerhard Herzberg

NRC Ottawa researcher Dr. Gerhard Herzberg said he was inspired to identify molecules and atoms by their emission and absorption of light because of astronomical puzzles.

Dr. Herzberg identified molecules in comets, planetary atmospheres, and interstellar space. This led to his Nobel Prize in Chemistry in 1971, work that continues to have wide application in history. 

Dr. Andrew McKellar

DAO astronomer Dr. Andrew McKellar determined in 1940 that carbon-based molecules existed in interstellar space, and measured their temperature at 2.4 degrees above absolute zero. The source of this puzzling temperature was revealed more than two decades later to be caused by heat left over from the Big Bang.

Radio Waves from the Sun

The NRC commenced daily monitoring of radio emissions from our Sun in 1946, and by the end of that year discovered that the solar atmosphere is much hotter than the visible surface of the sun.

Initially done from Ontario, the NRC continues daily solar monitoring from Penticton, BC. Solar activity can affect telecommunications and power grids. This long-term record of the sun's activity is also invaluable for understanding space weather and also provides data for climate modelling.

The Science

Stellar AtmosphereS

Work at the DAO after WWII continued to focus on improving our understanding of stars, including their mass, luminosity, and chemical composition.

Dr. Ann Underhill wrote the first computer program that simulated the atmospheres of stars at a time when other researchers did numerical calculations on hand-cranked adding machines. Dr. Jean McDonald also did ground-breaking work at the DAO in 1955 in modelling stellar atmospheres using University of Toronto's FERUT computer.

the galactic neighbourhood

Staff members expanded on the pioneering work by the DAO's Plaskett and Pearce in the 1920's and 30's by further defining the rotation of the Milky Way at different distances from the galaxy's centre, and in understanding the gas and dust clouds between the stars. A census of how many stars were in the solar neighbourhood and how much dust clouded and reddened our view was conducted at the DAO, work with wide application in astronomy such as measuring distances.

Multiple Star Systems

Upon joining the staff in 1959, Dr. Alan Batten sought to complete the extensive survey of multiple star systems begun by Plaskett in 1907. This culminated in successive editions of the definitive "Catalogue of the orbital elements of spectroscopic binary systems" in the 1960's through the 1980's.

One of the key results was that most of the stars that appear to be a single point of light to our eyes are multiple star systems, which are more common than solitary stars like our Sun.

Radio Astronomy

A focus in Canada on radio telescope technology and the structure of the Milky Way led to the creation of the Dominion Radio Astrophysical Observatory near Penticton, BC, resulting in sophisticated maps of our Galaxy and studies of the molecular clouds in it. The NRC's solar monitoring program was moved to this site and continues to this day.

In 1967, Canadian astronomers successfully linked radio telescopes in Penticton and Algonquin Park, Ontario. This offered the effective resolving power of a radio telescope 3,074 km wide, an internationally celebrated technical achievement routinely employed today as Very Long Baseline Interferometry. 

New Technology

Canadian astronomers in the 1960's began to feel the need for larger telescopes, particularly as many universities in Canada began doing research in forefront of astrophysics involving very faint objects. Canada's partnering in the 3.6-m Canada France Hawaii telescope project began an era of international partnerships in building large telescopes and innovative instrumentation.

These challenging projects also launched a new era of Canadian business being involved in related high tech astronomical engineering. The astronomical technology program at the DAO that grew out of the CFHT project began producing exceptional new instruments to get the most out of telescopes. Some of this work was carried out in Penticton.

Black Holes

In 1983, David Crampton and John Hutchings of the DAO, together with Anne Cowley, found the first black hole with the mass of a star located outside of the Milky Way. In 1984, John Hutchings, Bruce Campbell, David Crampton and radio astronomer Anne Gower discovered that Quasars are at the centre of every galaxy, and are now known to be powered by black holes weighing millions or billions times the mass of our Sun.


In 1980, Gordon Walker and Bruce Campbell of UBC tested their method on the DAO's 1.2-m telescope for improving the precision of velocity measurements in the line-of-sight. They accomplished a factor of 30 improvement.

They moved their device to the CFHT, and tentatively announced in 1988, with colleague Stephenson Yang of UVic, that a planet had been found orbiting the star Gamma Cephei. Variations on their method employed by others have resulted in the discovery of hundreds of exoplanets.