This subject seems to have had a bit of a revival again. The red rain of Kerala was speculatively linked to a fireball (and meteorite) over Kerala in southern India a few years ago – but was dismissed by mainstream. In the latest incident it may not be so tenuous – but then again, the Panspermia people are having a job to get their theory across even when they claim to have it under the microscope. A paper published in the Journal of Cosmology was designed to get Panspermia back off the ground after taking a bit of a pasting recently – including the red rain incident (http://phys.org/print282309406.html).
It seems a fireball that appeared over Sri Lanka in December 2012 was a meteorite that somewhat controversially, may have contained algae fossils. The research was led by Jamie Wallis of Cardiff University (in the forefront of Panspermia research as a result of Chandra Wickramasinghe) and he is suggesting this is direct evidence of life in comets and asteroids (and their offspring, meteorites). Some 600 plus fragments of the meteorite were sent to Cardiff University by a medical research institute in Colombo. Electron microscopy revealed what appeared to be fossils of algae embedded in the chondrite meteorite and according to Wallis this confirms life on earth had an extraterrestrial origin.
Critics are not impressed however, and have come up with a variety of reasons why this research should be ignored. The stock answer to research in a laboratory which comes up with unwanted results, is contamination. Yes, that has been one of the accusations aimed at Wallis and Wickramasinghe, an attack on the person and his methodology rather than addressing the subject in a clear headed fashion. The researchers hit back by saying the fossils were found deep within the rock matrix and this indicates, surely, they are of ancient origin. This was to no avail apparently as next questioning was about the fragments themselves – were they really from the meteorite. Might they be terrestrial rocks. They also said that lightning might have formed the fragments (if not a meteorite) which is interesting in ways not appreciated by the critics.
Another critic suggested the stones originated on Earth but were flung into space long ago during an impact event and reappeared in the atmosphere in December. Mind, the critics do have some things in their favour. What is surprising is that all the fossil samples were freshwater speciesof algae that live on earth nowadays – so it is possible the rock fragments are contaminated in some way. On the other hand if such algae did have an extraterrestrial origin it would not be surprising they are similar. Whatever, the controversy is bound to continue – and as frustrating as it is to the Wickramasinghe team the rest of us find it stimulating.
See also arxiv.org/abs/1303.1845 for further information or simply go to www.journalofcosmology.com and tease out the article. They have plenty of other articles on Panspermia and other controversial hypotheses.
Funny coincidence but a paper authored by researchers at UC Berkeley and the University of Hawaii have shown that complex molecules can form on icy dust in space suggesting that comets may have brought such molecules to earth and seeded the growth of more complex building blocks of life. This is quite different from what the University of Cardiff people are saying as the algae in the space rock is the same as algae on earth – but see www.geneticarchaeology.com/research/New_evidence_that_comets_could_have_…