Australia's Great Melbourne Telescope has been reassembled to celebrate the 150th anniversary of its installation at the Melbourne Observatory in 1869. Once the second-largest telescope in the world and the largest in the southern hemisphere, the 48-in (1.2 m) reflecting telescope has been restored thanks to an 11-year volunteer effort after being severely damaged in a bushfire in 2003.
The Great Melbourne Telescope was originally built in 1868 by Thomas Grubb in Dublin, Ireland before being disassembled and shipped to Melbourne for installation in the observatory next to the Royal Botanical Gardens. After it was properly adjusted, it was used for decades for a variety of research projects.
When the Melbourne Observatory closed in 1944, the telescope was sold to the Australian Government's Mount Stromlo Observatory near Canberra and was upgraded with a new 50-inch (1.3 m) pyrex mirror, followed by a new equatorial mount and state-of-the-art instruments in the 1990s, including a computerized digital imaging telescope for the study of dark matter.
Unfortunately, bushfires in January 2003 destroyed the observatory, reducing the telescope to its heavy cast-iron backbone and not much else. In 2008, staff and volunteers from Museums Victoria uncovered the remains and set about restoring it as a joint project of Museums Victoria, the Astronomical Society of Victoria, and the Royal Botanic Gardens Victoria with the aid of a AU$600,000 (US$405,000) grant from the Victorian State Government.
The restoration effort required over 1,000 engineering drawings and over 500 workshop sessions as well as 30,000 volunteer hours by engineering and astronomy experts. The work involved cleaning and cataloging the surviving parts, and manufacturing of almost 400 missing components, and what one volunteer claims is a world record for the most WD40 required for the cleaning effort.
"We had only 65 percent of the original parts, a few historical photos and some technical drawings as a starting point," says Senior engineering curator, Matthew Churchward."We want to make sure we are retaining the historical integrity of the telescope by returning it to its 1860s specifications, using similar materials and manufacturing techniques to the original."
Now on display at the Pumping House at Scienceworks in Melbourne, the ultimate goal is to reinstall the telescope in the Telescope House at the Melbourne Observatory. The next step will be to secure AU$1.5 million to make the telescope fully functional again and the centerpiece of a new public astronomy program.
"Our aim is to restore the telescope to operating condition so that the next generation of astronomy enthusiasts can peer through its giant eyepieces and be awe-inspired by magnificent views of celestial objects in our southern skies," says Engineering curator, Matilda Vaughan.
Source: Museums Victoria