Another is that ''una'' means ''oneness'' and there's a metaphysical and astronomical element to the work. It comprises one sphere inside another. The outer one, four metres in diameter, has 9100 perforations in it. Looking through one of them reveals thousands of tiny light specks reflected on the polished surface.

''The surface itself is reflective: you see the sculpture itself, it's seeing itself and its reflection and you see yourself,'' Buttress said.

The perforations, designed in collaboration with astronomer Dr Daniel Bayliss, from ANU's research school of astronomy and astrophysics to ensure scientific accuracy, represent the stars visible to the naked eye, sized according to their luminosity.

''It's like looking at a microcosm of the universe,'' he said.

Buttress, 48, was commissioned to create the sculpture in March last year and said it took months to research and plot the perforations to represent the stars correctly, using a computer program.

''My interest is in the stars and trying to express the sublime,'' he said.

He studied at Trent University in Nottingham and has created many sculptures in steel, bronze, corten steel and glass. ''This is one of the more modest ones,'' he said.

Buttress has created many works in Asia, Europe and the United States. Last year in Belfast he created RISE, a 40-metre high sculpture comprising two domes, one inside the other, and placed between the Protestant and Catholic communities.

A time-lapse video showing the installation of RISE will be shown at the ANU Drill Gallery as part of an exhibition of Buttress' work that includes paintings, sculptures and maquettes.

As part of the Centenary of Canberra Festival, this exhibition was included in the TOUCH: Sculpture and the Land program celebrating Canberra's public sculpture.

UNA is on display and the exhibition is at the ANU Drill Hall Gallery until June 23. Click here for more information