Ian Halliday
The Canadian astronomer who built a network of fireball cameras across the prairies and recovered the Innisfree meteorite in 1977.
Key facts
- Born
- 1928
- Died
- 2018
- Nationality
- Canadian
- Field
- Astronomer
Ian Halliday worked for many years at the National Research Council of Canada in Ottawa, where he studied meteors and the light they give off as they burn up in the atmosphere.
In 1971 he and his colleagues set up the Meteorite Observation and Recovery Project, known as MORP. It was a network of 12 automatic camera stations spread across the Canadian prairies in Alberta, Saskatchewan and Manitoba, designed to photograph bright fireballs from several places at once so that their paths and likely landing sites could be calculated.
On the evening of 5 February 1977 the cameras recorded a fireball over Alberta. From the photographs, the team worked out where pieces should have fallen, and searchers found the first stone, of about 2 kilograms, in the snow near the village of Innisfree. Further pieces were found later. Innisfree was the third meteorite with a precisely measured orbit, after Příbram and Lost City, and like them it came from the asteroid belt.
Over about 14 years, Halliday's network photographed hundreds of fireballs. His analysis showed how many meteorites of different sizes fall to Earth each year, figures still used to estimate the rate of meteorite falls.
On the timeline
- 5 February 1977Innisfree: Canada's camera network succeeds