In 1970 he graduated in Mathematics at the University of Milan and later he studied at the Scuola Normale Superiore di Pisa.

He is the founder of the two web services NEODyS[5] and AstDyS,[6] dedicated to providing general information on all known asteroids.

He also served as member of the Steering Committees of Divisions 1 and F.[8] Among his hobbies, he enjoyed writing science fiction stories.

[9] Milani co-authored a book with Anna Maria Nobili and Paolo Farinella on non-conservative forces on artificial satellites.

More recently, he published a book with Giovanni Federico Gronchi on orbit determination and impact monitoring.