Two men who painted an anti-war slogan on Sydney's Opera House have been sentenced to nine months of weekend detention.
Mr Saunders and his friend were protesting against the Iraq war
Australian David Burgess, 33, and Briton Will Saunders, 43, were convicted last year of daubing "No War" in giant red letters on the landmark.
They were protesting at Australia's involvement in the US-led invasion of Iraq.
They have also been ordered to pay almost £50,000 in compensation.
The two men will now have to spend every weekend for the next nine months behind bars, after being sentenced to periodic detention.
Saunders, who has worked at the Anglo-Australian Observatory for the last four years, could find himself in more trouble with the immigration authorities, says the BBC's Phil Mercer.
They are expected to review his working visa in light of his jail sentence, our correspondent says.
Lawyers for both men have said they will appeal.