The entrance to the Plutonium cave.
However, today, scientists have lifted the mythological curtain behind this seemingly supernatural phenomenon. According to a study published in the Journal of Archeology and Anthropology in February last, a fissure in the earth’s surface, is located deep inside the cave has produced CO 2 concentrations “death ” . Specifically, with a portable gas analyzer, Mr. Hardy Pfanz and a team of volcanologists found CO 2 with a concentration of 4-53% at the mouth of the cave and the highest at 91% inside. This concentration is more than enough to kill all living things.
“Mammalian species (including humans) can start to have problems at less than 5% CO 2, ” Pfanz told CNN. “At 7%, the longer you stay, the more severe the symptoms like sweating, dizziness, increased heart rate. Higher concentrations lead to suffocation due to lack of oxygen as well as blood, brain cells … acidified.”
Therefore, all animals that enter the cave quickly collapse. Pfanz revealed that during the research, the team found the carcasses of several birds, mice and more than 70 beetles.
During the day, this gas is scattered by sunlight. The cave becomes most dangerous at dawn, the volcanic gas that accumulates overnight enough to kill all living things nearby.
At dawn, carbon dioxide concentrations reach 50% at the bottom of the lake in the cave, up to 35% at 10 cm but begin to decline rapidly at 40 cm and above. This elevation accumulation also explains the ghostly recorded event, that when the Roman priests led the ox near this “gate of hell” , the ox died but the man was fine: simple Simply put, a person standing upright is much taller than an animal, thus avoiding the release of toxic gases.
Like in the past, today, Plutonium still attracts thousands of visitors each year. Italian archaeologist Franceso D’Andria – who rediscovered the cave in 2013 – said he and his colleagues also found evidence of a stage once erected around Plutonium to serve the Ancient travelers.
The ancient Greek geographer Strabo once described: “ Any animal that goes inside will face instant death . The bulls that were led inside all collapsed and were dragged outside. I threw in a few sparrows and they immediately fell , ” he wrote.
The graphic simulates the buildings surrounding Plutonium, including the seats for the audience.
Strabo realized this reaction was related to the gas – “space is full of smoke, so dense that the ground cannot be clearly seen” – but does not understand why the gas affects the animals but the monks and did not bother. He said that they may be protected by gods or simply monks who held their breath when entering the cave.
However, Mr. Pfanz’s research has also revealed the mystery behind this: the monks and the animals are of different heights ! It is known that CO 2 is heavier than oxygen, so it will sink to the bottom, forming a toxic “gas lake” on the ground. Therefore, the animals will “have enough” and the monks will be safe.
“The noses of the animals are right in the middle of the lake , ” Pfanz said.
In addition, Mr. Pfanz said that the monks knew well about the origin of the “breath of death” as well as the change in gas concentrations at different times of the day. The study results also show that the concentration of CO 2 is high at dawn and dusk because gas was dispersed sunlight. However, archaeologist D’Andria disagrees with this view. He said that, based on the many oil lamps found at the cave entrance, “it is very likely that many religious activities were carried out at night”.
Thus, the “gate to hell” is actually a hiding place for a rather dangerous scientific phenomenon. However, the ancient city of Hierapolis still becomes one of the attractions that attract thousands of tourists not only because of the Plutonium cave but also because it has hot springs. If you have the opportunity to visit this place, remember to pay attention to safety!