(Indiana University, Bloomington, Indiana, USA)

This video was featured in the exhibition, “Augustus: The Art of Command,” which was shown in the Ara Pacis Museum (Rome, Italy) from April to September 2014 on the occasion of the two thousandth anniversary of the death of Rome’s first emperor. The video presents a 3D reconstruction of the northern Campus Martius, a part of the city of special interest to Augustus and which he was the first to develop. Several key monuments survive from Augustus’ intervention, including the first obelisk brought to Rome (the so-called Montecitorio Obelisk) and the Ara Pacis, a 10 x 11 m altar open to the sky decorated with a series of reliefs that represent the peak of Roman art in the Augustan age. The monuments have been re-erected in new sites in the modern city, and the area of the ancient city where they originally stood has changed beyond all recognition. Only through a 3D reconstruction model could this part of Rome be restored to the way it appeared in the reign of Augustus (30 BC – 14 AD).
The team behind the video resurveyed the monuments and created a scientific 3D reconstruction model accurate to +/- 1 cm. It also used altazimuth data from NASA’s highly accurate Horizons System in order to simulate the path of the sun through the sky during the reign of Augustus.
The concept is that the video illustrates the proximity and alignment of the Obelisk and Ara Pacis. It also illustrates the innovative published research of Albèri Auber, who showed that the obelisk functioned as the gnomon of a giant meridian whose purpose was to facilitate calculation of the leap year by the Romans. In the thirty six years prior to construction of this monumental complex, the Romans had miscalculated the leap year, which was already in error by three years when Augustus assumed responsibility as pontifex maximus for the maintenance of the religious calendar.
The informational value of the video is high: it shows the way in which the shadow cast by the gnomon onto the meridian moves from year to year in the four-year cycle from one leap year to the next, returning to the initial position in the fourth year. Before the video was created, Albèri Auber had only been able to describe this phenomenon in words and with a static, 2D graphic that was quite hard for people outside the field of gnomonics to read.
The entertainment value consists in the lyrical style of the video used to reinforce the beauty of the monumental complex created by Augustus.
In short, the video demonstrates the strengths of Virtual Heritage to bring antiquity to life, make complex mathematical-astronomical calculations intuitively obvious through dynamic illustrations, and inspire young people and the general public to better appreciate the richness of our cultural heritage.

Keywords: 3D reconstruction, archaeoastronomy, Roman archaeology