From July to September 2001, heavy downpours of red-colored rain fell across the southern Indian state of Kerala, staining clothes pink.
Yellow, green, and black rain also appeared.
Each milliliter of rain water contained about 9 million red particles.
Godfrey Louis and Santhosh Kumar posted a paper titled "Cometary panspermia explains the red rain of Kerala," arguing that a meteor had deposited extraterrestrial biological cells in the atmosphere.
The colored rain has also been reported in Kerala in 1896, 1957, and again in 2012.
From July to September 2001, heavy downpours of red-colored rain fell across the southern Indian state of Kerala, staining clothes pink. Yellow, green, and black rain also appeared. Each milliliter of rain water contained about 9 million red particles. Scientists estimated that 50,000 kilograms of them fell in total.
A government investigation identified the culprit: airborne spores from Trentepohlia, a common green alga that happens to be bright orange. Field inspectors found that "almost all the trees, rocks and even lamp posts in the region were covered" with it.
But two physicists at Mahatma Gandhi University weren't satisfied. Godfrey Louis and Santhosh Kumar posted a paper titled "Cometary panspermia explains the red rain of Kerala," arguing that a meteor had deposited extraterrestrial biological cells in the atmosphere. They claimed the cells could reproduce at 300 °C and contained no DNA — claims that have never been verified in any peer-reviewed publication.
The colored rain has also been reported in Kerala in 1896, 1957, and again in 2012.
