In 2024, we celebrate the 100th anniversary of Mt Stromlo Observatory's founding, when it was established as the Commonwealth Solar Observatory in 1924. Its origins, evolution, and history not only intertwine into the history of Canberra, but it has been at the forefront of expanding our knowledge of the Universe, and making some of the biggest discoveries.
The origins of Mt Stromlo go back much earlier though than 1924.
At the turn of the 20th century, there was an international project to establish a world-wide network of telescopes in order to study the Sun constantly - 24 hours a day. Observatories were established in places like the UK, the US, and India.
There was a gap in coverage though - located around the location of the east coast of Australia. Australia had the further advantage of being in the Southern Hemisphere, so during our summer, we could monitor the Sun for longer when the Northern Hemisphere observatories were in winter and could not.
The project was led by the UK and the Smithsonian Institute in the US. One of the astronomers in the UK, Walter Duffield, was originally from Adelaide and part of the discussions to set-up this global network.
Taking the lead, he lobbied Australia to build a solar observatory as part of the international project. Firstly, in the early 1900s, he asked the South Australian government for support. They said this was more a of a federal government project, so to go ask them.
The federal government, while supportive of the idea, had no money, having spent their science budget on the establishment of the Bureau of Meteorology.
During the lobbying phase to support funds, the establishment of the ACT was coming in, and the project found a home in the ACT as a national observatory.
An initial telescope, led by the Victorian astronomer Pietro Baracchi, was to be built in Canberra. It would cost 10,000 pounds to build, and 27 pounds a year to operate. The telescope itself came from a donation from James Oddie. Oddie, who made was in Victoria for the gold rushes, lived in Ballarat and was a known philanthropist. He gave his prized telescope to the effort to establish a national observatory.
Having the telescope, and agreement on initial set-up, five choices of mountains were examined. Mt Ainslie and Black Mountain, while higher than Mt Stromlo, were going to be too close to the future capital - so a more remote location was chosen. Out of the remaining three choices, Mt Stromlo was chosen due to having the best weather.
Originally, known as Mt Strom, the origin of the name is unknown - not being a local Ngunnawal or Ngambri name, nor having a clear association with any origin.
In 1910, construction on the four-room observatory building, eventually called the Oddie Telescope, began. Construction finished in September, 1911, which makes it the first commonwealth building in the ACT.
Baracchi and an assistant spent many months on the mountain, taking measurements on the suitability of the site to host the national observatory.
However, the outbreak of World War I delayed the building of the rest of the telescopes and equipment and establishment of the Commonwealth Solar Observatory, until 1924.
- Brad Tucker is an Astrophysics and Cosmologist at Mt Stromlo Observatory and the National Centre for the Public Awareness of Science at the ANU.
