Jupiter Tonans
Jupiter Tonans, or, in Latin spelling, Iuppiter Tonans was the aspect of Jupiter venerated in the Temple of Iuppiter Tonans, which was vowed in 26 BCE by Augustus and dedicated in 22 BCE on the Capitoline Hill; the Emperor had narrowly escaped being struck by lightning during the campaign in Cantabria. An old temple in the Campus Martius had long been dedicated to Iuppiter Fulgens. The original cult image installed in the sanctuary by its founder was by Leochares, a Greek sculptor of the 4th century BCE.
In the 1st century Vitruvius observed the propriety or decorum required for temples of Jupiter Tonans, that they be hypaethral, open to the sky. The 1st century poet Lucan also mentions the temple of Jupiter Tonans in Rome.
The sculpture at the Prado is considered to be a late 1st century replacement commissioned by Domitian. The Baroque-era restoration of the arms has given Jupiter a baton-like scepter in his raised hand.