Finally chapter 23 is ready. I had written the few preceding chapters with 80mg of cortisone daily and I can testify that it was way easier!
Chapter 23: Life in Comets?
In the following chapter we use cometary material and meteoritic material interchangeably because meteorites, especially, carbonaceous chondrites, are the results of the non-volatile frictions of comets
[1].
So far we’ve seen that cometary events were the cause of most, if not all, mass extinctions and probably of the two most severe pandemics recorded in history. Like mass extinctions that were followed by life explosions, the two plagues were followed by a civilizational leap.
Knowing the central role played by virus in the genetic code of life-forms as shown in the previous part
[2], we suspect that the infusion of new viruses triggered the evolutionary leaps that mark the aftermath of cometary-induced mass extinctions.
But how can we explain this strong association between comets and viruses? Can cometary material carry viruses? Can viruses even “survive” the extreme condition of a cometary journey? This chapter provides some answers to these questions.
Organic material in meteorites
All known life forms are based on organic
[3] molecules
[4]. Conversely, most organic molecules are produced by life forms, especially micro-organisms, for example bacteria for the production of insulin
[5] or yeast for the production of ethanol
[6].
For reference, the total annual primary production of biomass is estimated be over 100 billion tons per year
[7] of which as significant amount
[8] is produced by microorganisms particularly bacteria and diatoms (phytoplankton). For example the diatoms alone are responsible for 20 to 50 % of the oxygen produced on Earth each year
[9] and they constitute about 50% of all the organic material found in the oceans
[10].
© Landgrebe
Polarized picture of a fossilized diatom (anthodiscina floreata)
The above suggests that the large quantity of organic material found in comets has to be produced by life-forms. That was the theory held by the vitalists
[11] for centuries. Nowadays researchers like Hoyle or Wickramasinghe make a similar claim:
It is
impossible to synthesize organic materials in appreciable quantity from inorganic materials without the intervention of biological systems[12]
As early as 1908, meteorites were suspected to be an important source of terrestrial organic compounds
[13]. These suspicions were confirmed in the 1960’s with the discovery of organic molecules in space
[14] and in comets
[15]. Since then, cometary organics has been widely documented
[16].
For example, Halley’s Comet alone revealed an impressive variety of organic material:
Analysis of the dust grains streaming from the head [of Halley’s comet] revealed that
as much as one third was organic material. Common substances such as benzene, methanol, and acetic acid were detected, as well as some of the building blocks of nucleic acids.
If Halley is anything to go by, then comets could easily have supplied Earth with enough carbon to make the entire biosphere.
[17]
Not only Halley’s Comet releases a wide array of organic materials but also the emanated quantities are truly astounding:
We know as a matter of fact that
comets do eject organic particles, typically at a rate of a million or more tons a day. This was what Comet Halley was observed to do on March 30-31, 1986. And Comet Halley went on doing just that, expelling organic particles in great bursts, for almost as long as it remained within observational range.
[18]
© ESA
Photograph taken from the probe Giotto showing the nucleus of Halley's Comet
Halley’s Comet is not an oddity, pretty much all the comets closely observed revealed a similar organic signature:
An independent analysis of dust impacting on mass spectrometers aboard the spacecraft Giotto also led to a complex organic composition that was fully consistent with the biological hypothesis.
Broadly similar conclusions have been shown to be valid for other comets as well, in particular Comet Hyakutake and Comet Hale-Bopp.
[19]
Amino acids
Among organic material of cometary origin, there is an unexpected variety of amino acids, which are the building blocks of proteins. No less than 52
non-biological amino acids have been found in the
Murchison meteorite
[20] alone. For comparison, the human body can only produce 20
[21] different amino acids, while about 500
[22] naturally occur on the whole planet.
The Murchison meteorite is not an isolated case. More than 50 years a variety of
extraterrestrial amino acids were found also in the
Orgueil meteorite:
Lawless (1972) concluded that the Orgueil meteorite, it Type I chondrite which fell in France in 1864 contained
several amino acids of extraterrestrial origin. Using gas chromatography, they isolated the
D-isomers of alanine, proline and aspartic acid. (It is well known that virtually all amino acids produced by terrestrial life forms are the L-isomer.) They also found
isomers of several unusual amino acid analogues: cr- aminoisohutyric acid, f -anlinoisohutyric acid, N-methylglycine, N-methylalanilie, and others, which are not found in proteins and are seldom associated with living plants and animal tissues.[23]
Cometary material contains of wealth of amino acids and the quantities are not negligible either, it is estimated that about 3% of the organic carbon in carbonaceous chondrites is in the form of amino acids
[24].
Beside the exotic amino acids found in the Orgueil meteorite, the presence in meteoritic material of more usual amino acids has been widely documented
[25]. The presence of adenine, guanine, cytosine, thymine and uracil, which are the five amino acids
[26] constituting of DNA and RNA, have been reported. Logically, the simplest amino acid, glycine, is the most abundant in chondrite meteorites
[27].
Kerogen:
It’s a complex waxy mixture of hydrocarbon compounds. It is the primary
organic component of oil shale. Optical analysis of the Murchison meteorite and of kerogens is virtually the same
[28], suggesting that the Murchison material contain a significant amount of kerogens.
Sugars:
An analysis of meteoritic material found that they contain sugars, including ribose, which is the backbone of DNA and RNA:
In the powdered samples of two ancient, carbon-filled
meteorites, astronomers have found traces of several sugars that are key to life —
including ribose, the sugary base of RNA
[29]
Organic polymers
POM stands for PolyOxyMethylene it is a polymer of an organic compound: formaldehyde.
The
positive detection of POM in the Allende carbonaceous chondrite is also of considerable interest in connection with the present theory. The chondrites are also probably typical of cometary meteoroids.
[30]
Aromatic molecules:
Aromatic molecules have been positively identified in the Murchison meteorite:
Aromatic material extracted from the Murchison meteorite shows absorption at ~2011 Angstroms
[31]
Space is populated by interstellar dust / grain. The estimated number of comets is 1014 and their tails can reach millions of km making them the major contributors of interstellar dust
[32]:
The sources of biological particles in interstellar clouds are […] an individual comet is a rather insubstantial object. But our solar system possesses so many of them, perhaps more than a hundred billion of them, that in total mass they equal the combined masses of the outer planets Uranus and Neptune, about 1029 grams. If all the dwarf stars in our galaxy are similarly endowed with comets, then the total mass of all the comets in our galaxy, with its 10ll dwarf stars, turns out to be some 1040 grams, which is just the amount of all the interstellar organic particles..
[33]
“Planetary nebulae” mentioned in the quote below are constituted interstellar grains who revealed the optical signature of aromatic molecules:
The expected emission features from an ensemble of naturally-occurring aromatic molecules is shown to be in satisfactory agreement with the emission properties of 'PAH molecules' associated with planetary nebulae.
[34]
The list of organics found comets and interstellar grain (comet dust) keeps increasing:
The range of interstellar organic molecules detected to date has expanded considerably to include water, carbon dioxide, acetone, ethyl cyanide, ethanol, a large number of hydrocarbons including polyaromatic hydrocarbons, acetic acid [vinegar] and also a provisional detection of the amino acid glycine.
[35]
To this list we can add extraterrestrial amino-acids, the five amino acids constituting DNA and RNA, organic polymers (POM), sugars and kerogens
[36].
As early as the 1970’s, Chandra Wickramasinghe and Fred Hoyle started to publish papers about the presence of organics in cometary material. For decades they were ridiculed by mainstream science until the amount of cumulated evidence couldn’t allow a denial anymore. Now mainstream science recognizes that Wickramasinghe and Hoyle were correct
[37].
Remember this quote by the same Wickramasinghe and Hoyle:
It is
impossible to synthesize organic materials in appreciable quantity from inorganic materials without the intervention of biological systems[38].
Since the “biological systems” are the only ones able the produce organic material in massive quantities and since organic materials are found in substantial quantities in comets, the obvious question is “
Do comets carry “biological systems”, especially microorganisms?
Microorganisms found in meteorites
Bacteria
Several researchers
[39] [40]including NASA’s head of astrobiology Richard Hoover have published numerous papers showing the presence of bacteria, fossilized or not, in meteoritic material.
That is the case, for example, for the Murchison meteorite that revealed very detailed cyanobacterial features
[41] through electron microscopy:
© NASA/MSFC
Fossilized cyanobacterial filaments in the Murchison meteorite
The bacterial content of the Murchison meteorite has been also confirmed by optical analysis. The diagram below shows a comparison between the spectra of bacteria E. Coli and the carbonaceous component of the Murchison meteorite.
[42]It displays virtually identical curves:
© Hoyle
The laboratory absorption spectrum of the Murchison meteorite compared with E. coli.
In addition to cyanobacteria and to E-coli, the examination of the Murchison meteorites revealed the presence of a third kind of bacteria that was confirmed through electron microscopy:
One can also note that Pflug has found very many objects in the carbonaceous material of the
Murchison meteorite that are morphologically of distinctive biological forms, as for instance the distinctive bacterium Pedomicrobium.
[43]
© Pflug
Comparison of a structure in the Murchison meteorite (left) with the bacteria pedomicrobium (right).
The Murchison meteorite is not an oddity, the examination of the Martian meteorite ALH84001 also showed the presence of bacteria:
A meteorite originating from Mars known as ALH84001 was shown in 1996 [David McKay] to contain microscopic structures resembling small terrestrial nanobacteria.
[44]
A major controversy followed this discovery. After all, this groundbreaking discovery meant, perhaps too early, that there once was life on Mars. So, the finding was dismissed on the ground of several arguments.
However, 13 years later, the same David McKay, published a paper tackling these arguments one by one, confirming the presence of bacteria in ALH84001, and cherry on the cake, showing the bacterial content in two additional Martian meteorites, namely Nakhla and Yamato-593
[45].
Not only fossilized bacteria were found in meteorites as shown by the examples presented above but researchers also found
viable extraterrestrial bacteria inside a meteorite:
On May 11, 2001, two researchers from the University of Naples claimed to have found
viable extraterrestrial bacteria inside a meteorite. Geologist Bruno D'Argenio and molecular biologist Giuseppe Geraci claim the
bacteria were wedged inside the crystal structure of minerals, but were resurrected when a sample of the rock was placed in a culture medium[46]
From 1997 until 2013, Richard Hoover published several papers proving the existence of indigenous microfossils of bacteria in the following meteorites: Ivuna
[47], Orgueil
[48], Murchison
[49], Murray
[50] and Polonnaruwa
[51].
These numerous discoveries of bacteria inside meteorites were confirmed by, yet, another method, namely optical analysis:
The infrared spectrum of Comet Hale–Bopp at 2.9 AU was shown to match the behavior of a mixture of microbes with a 10% contribution of silicates predominantly contributing only to the 10 μm feature. A very similar spectrum was obtained from the post-impact ejecta in the Deep Impact mission of 2005
[52]
Algae:
As early as 1963 a published paper showed the presence of fossilized algae in the Orgueil meteorite:
In the mid-1960's H. Urey, and later G. Claus, B. Nagy and D.L. Europa (Claus et al., 1963) examined the Orgueil carbonaceous meteorite which fell in France in 1864, microscopically as well as spectroscopically. They claimed to
find evidence of organic structures that were similar to fossilised microorganisms, algae in particular. The evidence included electron micrograph studies, which showed substructure within these so-called 'cells'. Some of the structures resembled cell walls, cell nuclei, flagella-like structures, as well as constrictions in some elongated objects to suggest a process of cell division.
[53]
© Eunostos
A fragment of the Orgueil meteorite exposed in Montauban Museum
These findings were indirectly confirmed one year later. Chlorophyll is one of the hallmarks of algae and porphyrins are the major precursor of chlorophyll. Coincidently or not, porphyrins were found in the Orgueil meteorite:
Hodgson and Baker (1964) found porphyrins in OrgueiI, but virtually no chlorins.
The porphyrins are complex organic molecules which are the foundation of chlorophyll and the oxygen carrying pigments in animal blood.
[54]
Besides the Orgueil meteorite, Claus discovered various diatoms - single-celled algae as known as phytoplankton – in other chondrite meteorites:
Many of the organized elements resemble Chrysophytes (related to diatoms) and Hystricho- spheres (fossilized dinollagellates, cysts and spore cysts of dinoflagellates). Some workers have also found diatoms (Nitzschia australis) and diatom-type structures in chondrites.
[55]
This discovery triggered a lot of controversies. So Pflug designed a method that used state-of-the-art equipment to prepare ultra-thin sections of the Murchison meteorite in a
contaminant free environment
[56]. This approach also kept the original structures of the microfossils intact and the results, once again confirmed the presence of microorganism in meteoritic material:
H.D. Pflug (1984) reopened the issue of microbial fossils in carbonaceous meteorites. Pflug used techniques that were distinctly superior to those of Claus and his colleagues and found a profusion of organized elements comprised of organic matter in thin sections prepared from a sample of the Murchison meteorite. The method adopted by Pflug was to dissolve-out the bulk of the minerals present in a thin section of the meteorite using hydrofluoric acid, doing so in a way that permits the insoluble carbonaceous residue to settle with its original structures intact. It was then possible to examine the residue in an electron microscope without disturbing the system from outside.
The patterns that emerged were stunningly similar to certain types of terrestrial microorganisms. Scores of different morphologies turned up within the residues, many resembling known microbial species.
[57]
In 2018, R.B. Hoover, founder and head of NASA astrobiology research corroborated Pflug's findings of diatom inside the Orgueil meteorite
[58].
A few years earlier, in 2012, the examination of a meteorite conducted by the University of Cardiff in Wales revealed, once again, the presence of diatoms. This finding was confirmed by research teams from United Kingdom, United States and Germany:
On 29 December 2012 a green fireball was observed in Polonnaruwa Province, Sri Lanka. It disintegrated into fragments that fell to the Earth near the villages of Aralaganwila and Dimbulagala and in a rice field near Dalukkane. Rock samples were submitted to the Medical Research Institute of the Ministry of Health in Colombo. The rocks were sent to the University of Cardiff in Wales for analysis, where Chandra Wickramasinghe's team analyzed them and claimed that
they contained extraterrestrial diatoms. From January to March 2013, five papers were published in the fringe Journal of Cosmology outlining various results from teams in the United Kingdom, United States and Germany
[59]
A few months later, in 2013, during an experiment called "Test", Russian cosmonauts Oleg Artemyev and Alexander Skvortsov identified a marine-type alga (phytoplankton) collected from the windows of the International Space Station, which is at a height of 420
[60] kilometers
[61]
Notice that ISS spaceships are launched from Baikonur, which is located in a desert. So the hypothesis of earthly contamination is unlikely.
© Artemjew.ru
Oleg Artemyev conducting the Test experiment.
Bacteria and diatoms are not the only microorganisms found in meteorites. Actually, Hoover found of a whole slew of them associated with ancient cosmic dust:
The discovery of organic material is also confirmed by ice core analysis in which Richard Hoover (2011), discovered
fungi, algae, cyanobacteria, nanobacteria, spores, diatoms, and protozoan in deep ancient ice cores over 4,000 years old, drilled from Lake Vostok, near the south pole.
These creatures were found in association with ancient cosmic dust particles which had fallen from space.
[62]
Viruses:
Positive identification of viruses in meteorites is extremely difficult because of at least two factors:
1/ Viruses are tiny. They are 10 to 100 times smaller
[63] than bacteria.
2/ only fossilized viral material will be possibly accepted while the non-fossilized viruses are automatically discarded as terrestrial contamination.
An indirect evidence of virus in comet is the positive identifications – as described above - of bacteria, which are eagerly colonized by virus (bacteriophages):
Bacteriophages are among the most common and diverse entities in the biosphere. Bacteriophages are ubiquitous viruses,
found wherever bacteria exist. It is estimated there are more than 1031 bacteriophages on the planet, more than every other organism on Earth, including bacteria, combined.
[64]
It is estimated that up to 31%
[65] bacteria are infected by bacteriophages. This percentage climbs to 70% for marine bacteria
[66].
Viruses are also omnipresent and play fundamental roles in the other microorganisms found in meteoritic material. They are a major regulator of phytoplankton (diatoms):
Marine viruses are recognized as a major driving force regulating phytoplankton community composition and nutrient cycling in the oceans
[67]
Likewise, many protozoans harbor viruses:
Increasing evidence is accumulating that many protozoan, but also helminth, parasites harbor a range of different classes of viruses that are mostly absent from humans. Although some of these viruses appear to have no effect on their parasite hosts, others either have a clear direct negative impact on the parasite or may, in fact, contribute to the virulence of parasites for humans.
Besides the indirect evidence listed above and despite the difficulties of identifying fossilized virus, direct evidence also exist.
Fossilized viral particles have been found in meteoritic material first by
H.D. Pflug in 1984
[68] and his finding was confirmed twenty years later by NASA head of astrophysics
Richard Hoover[69]:
© Joseph & Wickramasinghe
The Murchison meteorite revealed what looks like fossil viruses.
For comparison the drawing top right is a modern influenza virus
To strengthen the viruses-meteorites connection, here is the interesting case of very specific bacteriophages: the “Z viruses”
[70]. Unlike virtually all the other lifeforms on Earth whose DNA is made of the four usual nucleotides, namely: A (Adenin), T (Thymine), G (Guanine), and C (Cytosine); the genetic material of the Z virus is made of a unique set of four nucleotides, namely Z, T, G and C.
The unique nucleotide labeled Z stands for
diaminopurine, which is, coincidently or not, a compound found in meteorites:
The
Z base has been unambiguously identified in a carbonaceous meteorite and proposed as a nucleobase that could have been available for the origin of life
[71]
Similarly to the Z virus, the Yaravirus has not even one closely related genome among thousands of viruses’ entries:
Furthermore, we were not able to retrieve viral genomes closely related to Yaravirus in 8,535 publicly available metagenomes spanning diverse habitats around the globe. The Yaravirus genome also contained six types of tRNAs that did not match commonly used codons.
[72]
This oddity strongly suggests that Yaravirus is not from Earth but from space originally.
Another scientific data suggesting that virus initially from space is virtually perfect match between the optical signature of a mix Tobacco Mosaic Virus + E-Coli and the optical signature of GC IRS 6E and GC IRS 7
[73]:
The solid curves in Figure 10 combine the effects of two types of biological material: viral type particles typified by the laboratory data for TMV (Tobacco Mosaic Virus) and it desiccated bacterium represented by the data for E-coli.
[74]
© Wickramasinghe
Normalized optical depths for E. coli - TMV mixtures over the 3.3-3.6 J-Lm waveband (curves). The points are similarly normalized data for GC-IRS6 and GC-IRS7
[1] See Lescaudron, 2014 chapter 18: Comets or Asteroids?
[2] Part III : Viruses are the Drivers of Life
[3] There’s no scientific consensus about what an organic molecule is. They generally contain carbon-hydrogen or carbon-carbon bonds
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[60] About 260 mph
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[73] Two stars in our galaxy
[74] Wickramasinghe N., Hoyle F. (1998) “Infrared Evidence for Panspermia: An Update”
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