Reaching for the stars

Reaching for the stars

May 1, 2005

Canada has a remarkable record of excellence in astrophysics. Key federal funding decisions and an organizational approach developed a century ago laid the basis for this ongoing success. In return, astrophysical research has inspired legions of students and amateur astronomers, invented devices and developed technical expertise in co-operation with Canadian industries, and established Canada as an intellectual leader in astrophysics.

How did this develop?

In the early 1900s the Canadian government made the absolutely remarkable decision to allocate the then vast sum of approximately $310,000 to establish the Dominion Observatory (DO) in Ottawa. The intent was to demonstrate Canada’s technical and scientific maturity on the world stage. The DO was the national centre of practical astronomy: precision longitude, latitude, and time. The DO staff began such a vigorous program of astrophysical research that they quickly exhausted the capabilities of the telescope and related equipment. In the Report of the Chief Astronomer of 1911, Dr. J. S. Plaskett urged that Canada build the largest telescope in the world and acquire an unrivalled series of observations that would establish a reputation for Canadian astronomy that would be “second to none.”

The outcome was the Dominion Astrophysical Observatory (DAO) outside Victoria, British Columbia which opened in 1918 with a 72-inch aperture telescope, then the largest in the world. The DAO staff went to work on a program of collaborative, rather than individual, research that quickly dwarfed the efforts of astronomers at U.S. and European observatories. The scientific controversy of the 1920s was the nature of the galaxy and the Universe. The DAO data showed that the Sun was one of many stars that lie in a flattened disk rotating around a distant centre to our galaxy, rather than being located near the centre of the visible stars. This result was celebrated around the world, establishing the Canadian reputation for astrophysical excellence. Moreover, it set Canadian astronomy on a path of addressing fundamental physical questions and making effective use of research consortia to answer “big” questions.

In 1935, the David Dunlap Observatory was opened by the University of Toronto creating a forefront research opportunity for students and professors. It also staked out new research areas of age-dating the universe through the oldest stars, the rapidly developing subject of extragalactic astronomy (everything beyond our own galaxy), and the discovery of the first black hole.

A new era began in the 1970s when Canada was one of the first to step out fully into international astronomy. In an equal partnership with France, Canada built the Canada-France-Hawaii Telescope (CFHT) on a 4,200-metre Hawaiian peak above 40 percent of the atmosphere. The location, the superb mirror of the CFHT (finished in Victoria), and ongoing improvements produced much sharper images than available anywhere—until the advent of the (corrected) Hubble Space Telescope in the early 1990s. Moreover, the CFHT created economic opportunities for optics, electronics, and for high-precision, large-scale construction. In an impressive transformation, the CFHT contract given to the then railway bridge specialists Brittain Steel (now AMEC Dynamic Systems) turned an initial $6 million contract into about $500 million of business in telescope enclosures, and helped provide them with proven capabilities that allowed for numerous spin-off opportunities.

In the 40 years since the CFHT era began, astrophysics has moved on, as has technology. The two have combined to create fascinating new questions whose answers are now almost within our reach, such as those relating to extra-solar planets and “dark energy.” Through a technique of measuring “star wobble,” astronomers, have established that a large fraction of all stars have planetary systems. At the moment, all we know is that they are there. With larger telescopes, it will be possible to directly image Jupiter-size planets around nearby stars to study their properties and to follow the formation process as disks of dust and gas condense into planets. A second major development is the discovery that the expansion of the universe is speeding up. There is no known force in physics that explains this, but characterizing the “dark energy” is a major topic for new telescopes. And, with Extremely Large Telescopes (ELT), we will be able to characterize the first stars ever to form.

New technical developments in adaptive optics will give ELTs their ability to see much finer scale detail than ever before. Air currents and turbulence in our atmosphere “blur” the images of distant objects. Adaptive optics can measure and largely remove the distortion to produce space quality images, but at a vastly lower cost and with much larger telescopes than are currently feasible. The CFHT was a key test-bed for many of the early developments in adaptive optics. Ongoing developments have positioned Canadian astronomers and optics industries to contribute in this rapidly growing field.

How will Canada participate in these exciting intellectual opportunities and reap the associated benefits? Canada has become fully engaged in the ELT era through a new partnership between universities (the Association of Canadian Universities for Research in Astronomy) and the National Research Council. Canada has come to the table with a strong group of scientists, instrument makers, and precision-heavy industry that enable us to play a major role in the scientific direction and economic return of creating and operating what will surely be a landmark scientific facility of the early 21st century.

Canada’s distinctive contribution to astronomy includes definitive measurements of the age of the universe, the evolution of galaxies, and the mass density of the universe. Canadian astronomy citation rates per paper are currently ranked number one in the world, despite the fact that Canadian astronomy funding is significantly lower per capita than in most countries (about 2/3 of Australia, and 1/5 to 1/4 of the U.K., U.S., France, Germany, and Italy).

A largely home-grown set of astronomers continue to devise a uniquely Canadian approach to astronomy—capitalizing on our ability to focus our scientific resources on a critical mass of high-impact facilities. Canada’s success in astrophysics has won our country a position of intellectual distinction among the most advanced nations of the world. It has also inspired Canadian children to pursue careers in science, and has helped pay for itself through its calls upon our industries to collaborate and innovate. Big telescopes help raise our sights to the stars and the edge of the universe, but also help improve lives here on earth.

Ray Carlberg is a Professor at the  Department of Astronomy and Astrophysics, University of Toronto.

The views and ideas expressed in this column do not necessarily reflect those of the Canada Foundation for Innovation or its Board Directors and Members.