Baracchi was born in Florence and took a degree in civil engineering. In 1876 he sailed for New Zealand, but soon moved on to Australia. He gained work as an assistant at the Melbourne Observatory and was selected to be transferred to Darwin. After completing his task there to measure longitudes, he returned to Melbourne and became acting government astronomer on 30 June 1895 on Robert L. J. Ellery's retirement.
His wife died in 1908. Baracchi retired in 1915 and was succeeded as Government Astronomer of Victoria by Joseph M. Baldwin. In 1922 Baracchi visited Europe for two years and after his return he lived at the Melbourne Club. His son Guido Baracchi (1887–1975) was a founding member of the Communist Party of Australia.
- J. L. Perdrix, 'Baracchi, Pietro Paolo Giovanni Ernesto (1851 - 1926)', Australian Dictionary of Biography, Volume 7, MUP, 1979, pp 166–167
- Biography - Guido Carlo Luigi Baracchi - Australian Dictionary of Biography
- Baracchi, Pietro Paolo Giovanni Ernesto (1851 - 1926) at Bright Sparcs, University of Melbourne