Polonnaruwa (meteorite)

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Polonnaruwa
Type Alleged meteorite.[1]
Composition Olivine.[2]
Country North Central Province, Sri Lanka
Region Araganwila village
Coordinates 7 52' 59.5" N; 81 9' 15.7" E [3]
Observed fall Alleged.[1]
Fall date Allegedly fell on 29 December 2012.[1]
Found date Not published.[2]
TKW Not published.[2]

The Polonnaruwa meteorite is an alleged meteorite that fell on 29 December 2012 close to the city of Polonnaruwa in Sri Lanka, and recovered soon after by Chandra Wickramasinghe's team.[2][4][5][6]

Twelve days after the Polonnaruwa meteorite was "seen falling" to Earth, Chandra Wickramasinghe published in the online fringe science[7] Journal of Cosmology that, after studying some electron micrographs, his team discovered fossilized diatoms (microscopic phytoplankton) inside the meteorite as well as cells similar to those found in the Red rain in Kerala that fell in 2001.[2][5] In addition, his team of scientists reported in a separate article that they are certain that it is a meteorite that originated from a comet and that it also contained living diatoms.[5][6]

The rock is not deemed by peer scientists to be a meteorite,[1][8][9] so it was not recorded in the international Meteoritical Society database.[1]

Criticism

Though Wickramasinghe claimed that these microscopic shapes constitute strong evidence for panspermia,[2] astrobiologists have determined in the past that morphology cannot be used unambiguously as a tool for primitive life detection.[10][11][12]

On 15 January 2013 a diatom expert, Patrick Kociolek, verified that the forms pointed out in the paper are indeed diatoms. Then he added: <templatestyles src="Template:Blockquote/styles.css" />

"There certainly is not any sign of this being fossilized material. (...) the diversity present in the images represent a wide range of evolutionary history, such that the 'source' of the diatoms from outer space, must have gone through the same evolutionary events as here on Earth. There are no extinct taxa found, only ones we would find living today. For me it is a clear case of contamination with freshwater."

— Patrick Kociolek, [1]

Meanwhile, PZ Myers, who studies evolutionary developmental biology, questions "why a space organism would evolve to look exactly like a species that evolved in a completely different environment, and how it could have converged in all its details on such remarkable similarity to a specific Earthly species? Why, we might even suggest that it clearly looks like contamination."[13] While ignoring the environmental influence in evolution, a proponent of the panspermia hypothesis, Brig Klyce, contends that since life on Earth and life from space are closely related, resemblance would be expected.

Wickramasinghe's research paper was not peer reviewed by experts prior to publication, and early on, there were claims that Wickramasinghe's article was not an examination of a meteorite but of some terrestrial rock.[1][14] Scientists from the Peradeniya University Geology Division, and the Department of Forensic Medicine, as well as the Arthur C. Clarke Institute for Modern Technologies in Sri Lanka examined fragments of the alleged meteorite, and concluded that it is a terrestrial rock formed by lightning strikes (fulgurite).[9][15][16] The silica and quartz bulk content confirms the terrestrial fulgurite explanation, and further discards the meteorite hypothesis, as any silica in a meteorite would be present in trace amounts.[17] Another proposed explanation holds that the alleged meteorite did arrive from space, but is associated with the billions of tonnes of terrestrial material that asteroid impact events have previously blasted into space during the Earth's geological history.[18]

Rebuttal

Wickramasinghe's team remark that they are aware that a large number of unrelated stones have been submitted for analysis, and have no knowledge regarding the nature, source or origin of the stones their critics have examined, so Wickramasinghe clarifies that he is using the stones submitted by the Medical Research Institute in Sri Lanka.[3]

In response to the criticism from other scientists, Wickramasinghe performed X-ray diffraction [6] and isotope[3] analyses to verify its meteoric origin. His analysis revealed a 95% silica and 3% quartz content,[6] and interpreted this result as a "carbonaceous meteorite of unknown type".[6] In addition, Wickramasinghe's team remarked that the temperature at which sand must be heated by lightning to melt and form a fulgurite (1770 °C) would have vaporized and burned all carbon-rich organisms and melted and thus destroyed the delicately marked silica frustules of the diatoms,[3] and that the oxygen isotope data confirms its meteoric origin.[3]

Wickramasinghe's team also argues that since living diatoms require nitrogen fixation to synthetize amino acids, proteins, DNA, RNA and other life-critical biomolecules, a population of extraterrestrial cyanobacteria must have been a required component of the comet (Polonnaruwa meteorite) "ecosystem".[3]

Following a 29 April 2013 media briefing, Professor of Geology Athula Senarathna of the University of Peradeniya who carried out a research on the alleged meteorite, said that "there could not be any truth in Prof. Chandra Wickramasinghe's claim".[8]

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Lua error in package.lua at line 80: module 'strict' not found.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Lua error in package.lua at line 80: module 'strict' not found.
  4. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  5. ↑ 5.0 5.1 5.2 Lua error in package.lua at line 80: module 'strict' not found.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 Lua error in package.lua at line 80: module 'strict' not found.
  7. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  8. ↑ 8.0 8.1 Lua error in package.lua at line 80: module 'strict' not found.
  9. ↑ 9.0 9.1 Lua error in package.lua at line 80: module 'strict' not found.
  10. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  11. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  12. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  13. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  14. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  15. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  16. ↑ Lua error in package.lua at line 80: module 'strict' not found.
  17. ↑ Meteorite or meteowrong?. Department of Earth and Planetary Sciences, Washington University in St. Louis. Quote: "If you can see quartz with the naked eye, then the rock is not a meteorite."
  18. ↑ Lua error in package.lua at line 80: module 'strict' not found.
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