July 25, 2001 – Kottayam and Iduki districts, in Kerala, India –
A stunning phenomenon blew the society’s mind as red rain poured down from the sky after a very loud thunderclap and flash attracted their attentions. The mysterious rain didn’t last for no more than a few minutes. However, a series of red rain was reported within ten days since the noted day. At the same time, leaves in the surrounding of the area looked “burnt”. In September, the red rain stopped.
1. The History
Red rain or blood rain phenomenon has been debated for centuries. The first red rain ever reported is in the 8th century B.C., as written down on Homer’s Iliad. It was believed that the rain was actual blood and a bad omen until the 17th century A.D. By that time, people tried to find natural reasons to provide answers for the phenomenon. In the 19th century, some new theories were discussed. Some said that the red rain is caused by red dust dissolved in the water, or influenced by certain micro-organisms.
2. Theories for Kerala’s Red Rain
There were some theories provided to explain the phenomenon in Kerala at the beginning, such as:
- Dust Rain from Arabian Dessert
Days before the red rain fell, a cloud of dust was detected in the atmosphere near to Kerala. It rouse a speculation that the red rain was caused by the dust. This theory has been excluded once scientists didn’t find desert sand as one of the particles in the rain.
- Dust as a Result of Mayon Volcano Eruption in Philippine
K.K. Sasidharan Pillai, a senior scientific assistant in the Indian Meteorological Department stated that the red rain might be caused by dust and acidic materials of Mayon Volcano, Philippine, which erupted in June and July, 2001. It could explain why the leaves around the red rain area looked like being “burnt”. He thought the Eastern or Equatorial jet stream was the one to be responsible to transport the materials to Kerala. However, the theory was also eliminated soon after volcanic particles couldn’t be found in the rain.
- Exploding Materials from a Meteor
At first, Centre for Earth Science Studies (CESS) stated a possibility that the red particles in the rain was coming from a meteor which exploded and dispersed about one ton of materials. However, the theory was later doubted since they had no idea how the debris of the meteor kept on falling down to the same location for a long time, unaffected by the wind.
Later, CESS found out that the particles which caused the unusual color of rain were more like spores. The sample of the particles were later sent to Tropical Botanical Garden and Research Institute (TBGRI) for further investigation. The spores were apparently lichen-forming alga from the genus Trentepohlia. The spores could be found both from the rainwater and the trees at the area. Thus, both CESS and TBGRI concluded that the explanation of the red rain could be found around the trees at the area.
The scientists decided to visit the location of the red rain on August 16, 2001. They found a stunning discovery. Almost all the plants and rocks were covered with Trentepohlia with a lot of quantity, which was possible to cause such a rain of spores. They reported that the heavy rains in Kerala weeks before the red rain could have caused the widespread growth of lichens. Later, the spores were upraised to the atmosphere by the evaporation process. The spores were then back to the ground as the rain came.
The scientists were not 100% sure about the theory, but they couldn’t find more satisfactory explanation about what could cause such phenomenon.
Other than the Kerala red rain, similar phenomenons were also ever reported in Europe many times, and the newest report was in November 15, 2012 to December 27, 2012, when the rain fell in Sri Lanka.