Red rain in Kerala was a phenomenon observed sporadically from 25 July to 23 September 2001 in the southern Indian state of Kerala. Heavy downpours occurred in which the rain was primarily red, staining clothes and appearing like blood. Yellow, green, and black rains were also reported.
It was initially suspected that the rains were coloured by fallout from a hypothetical meteor burst, but the Government of India commissioned a study which found the rains had been coloured by spores from a locally prolific aerial algae. Then in early 2006, the coloured rains of Kerala suddenly rose to worldwide attention after media reports of a conjecture that the coloured particles are extraterrestrial cells, proposed by Godfrey Louis and Santhosh Kumar of the Mahatma Gandhi University in Kottayam.
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