The Meteorite That Changed The Course of Christianity
For more than two centuries, Christianity suffered under the Roman Empire. Christians were arrested, tortured, mutilated, burned, and starved. Christian buildings and the homes of Christians were torn down and their sacred books burned. The religious persecutions came to an end when Emperor Constantine ascended the throne. Unlike his predecessors, the emperor was a great patron of the Church. He built an extraordinary number of basilicas around the length and breadth of the empire, granted privileges to clergy, endowed the church with land and wealth, and even returned property confiscated from Christians by earlier rulers.
Battle of the Milvian Bridge by Giulio Romano, 1520-24.
What made Emperor Constantine convert to Christianity has been debated and discussed by theologians and historians for centuries. It is possible that Constantine's mother exposed him to Christianity from an early age. But many historians believe that Constantine experienced a dramatic event in 312 just before the Battle of the Milvian Bridge began, on the banks of Tiber on the outskirts of modern-day Rome, leaving a profound effect on the future emperor.
Eusebius, one of the Christian Church's early historians, describes a vision that Constantine had while marching towards the site of the battle:
...while he was thus praying with fervent entreaty, a most marvelous sign appeared to him from heaven, the account of which it might have been hard to believe had it been related by any other person.
...about noon, when the day was already beginning to decline, he saw with his own eyes the trophy of a cross of light in the heavens, above the Sun, and bearing the inscription 'conquer by this'.
At this sight he himself was struck with amazement, and his whole army also, which followed him on this expedition, and witnessed the miracle.
At first Constantine was unsure of the meaning of the apparition, but the following night he had a dream in which Christ explained to him that he should use the sign against his enemies. Constantine then commanded his troops to adorn their shields with the Christian symbol, the Chi-Rho, which he had seen in the skies. Constantine's army won the battle, and the new emperor dedicated the victory to Christ whom he believed had helped him.
But what was the celestial event that had such a transforming effect on Constantine?
Geologists believe Constantine had witnessed a meteorite impact, and the crater the impact had left behind is still out there in central Italy. The Sirente crater, located in the highlands north of the Sirente massif, is small and circular, and although there have been a lot of theories about its formation, Swedish geologist Jens Ormö believes it’s an impact crater.
“Its shape fits and it is also surrounded by numerous smaller, secondary craters, gouged out by ejected debris, as expected from impact models,” Ormö explains.
Radiocarbon dating puts the crater's formation at about the same time Constantine had his celestial vision. An impact generating a crater the size of one at Sirente would have been visible from a great distance. Before it hit, the meteorite would have blazed across the sky in a large fireball mesmerizing Constantine and his troops. It would have struck earth with the force of a small nuclear bomb, about one kiloton in yield.
The age of the crater also corresponds to local history. A nearby village was suddenly abandoned possibly because of fire during the 4th century. Catacombs dating to the same period reveal many bodies interred in a hasty manner. A local legend, passed orally, also provides a vivid description of the cataclysmic event. One version of the legend goes thus:
And then, an uproar hit the mountain and quartered the giant oaks announcing the violent arrival of the Goddess. A sudden and intense heat overwhelmed the people and a shout echoed all around, splitting the air with its trail of violence. All of a sudden, over there, in the distance, in the sky, a new star, never seen before, bigger than the other ones, came nearer and nearer, appeared and disappeared behind the top of the eastern mountains.
…Soon the star shone as large as a new sun. An irresistible, dazzling light pervaded the sky. The oak-leaves shuddered, discolored, curled up. The forest lost its sap.
The close spacing in both time and geography between the Milvian Bridge and the Sirente impact site have led researchers to reexamine the historic events. According to one study, Constantine and his military forces were camped only 100 km from the impact site before the battle of the Milvian Bridge. This must have given them a clear view of the mushroom cloud that would have likely arose following the impact, deeply influencing him and turning the tide of the conflict and the course of Christianity.