Authors_;
* Mr. Rupak Bhattacharya-Bsc(cal) Msc(JU) 7/51 Purbapalli, Po-sodepur; Dist 24 Parganas(north), Kol-110,West Bengal, India**Professor Pranab kumar Bhattacharya MD(cal) FIC Path(ind); Now Professor&HOD of Pathology At Calcutta School of Tropical Medicine CR avenue Kol-73 Ex Professor of pathology&HOD RIO,& Institute of Post Graduate Medical Education & Research,244 a AJC Bose Road, Kolkata-20, west Bengal, India **Miss Upasana Bhattacharya- Student, Mahamayatala, Garia, kol-86,only daughter of Prof.PK Bhattacharya***Mr.Ritwik Bhattacharya B.com(cal) Somayak Bhattacharya BHM MSC Student PUSHA,7/51 purbapalli, Po-sodepur Dist 24 parganas(north) , Kolkata-110,West Bengal, India******** Mrs. Dalia Mukherjee BA(hons) Cal, Swamiji Road, South Habra, 24 Parganas(north) West Bengal, India**** Mrs Oaindrila Mukherjee-student ,Swamiji Road, South Habra, 24 Parganas(north), West Bengal, India
* Mr. Rupak Bhattacharya-Bsc(cal) Msc(JU) 7/51 Purbapalli, Po-sodepur; Dist 24 Parganas(north), Kol-110,West Bengal, India**Professor Pranab kumar Bhattacharya MD(cal) FIC Path(ind); Now Professor&HOD of Pathology At Calcutta School of Tropical Medicine CR avenue Kol-73 Ex Professor of pathology&HOD RIO,& Institute of Post Graduate Medical Education & Research,244 a AJC Bose Road, Kolkata-20, west Bengal, India **Miss Upasana Bhattacharya- Student, Mahamayatala, Garia, kol-86,only daughter of Prof.PK Bhattacharya***Mr.Ritwik Bhattacharya B.com(cal) Somayak Bhattacharya BHM MSC Student PUSHA,7/51 purbapalli, Po-sodepur Dist 24 parganas(north) , Kolkata-110,West Bengal, India******** Mrs. Dalia Mukherjee BA(hons) Cal, Swamiji Road, South Habra, 24 Parganas(north) West Bengal, India**** Mrs Oaindrila Mukherjee-student ,Swamiji Road, South Habra, 24 Parganas(north), West Bengal, India
Panspermia Theory?
The big yet unsolved question is “are we alone in this universe?” If and even multi universes are present then is there also chance of development of life in planet or phantasmal in those universe? Paul Devis of Australian center for astrobiology Macquire university retired the claim of astrobiologists that life is cosmic in pattern bound to arise under earth like conditions and likely to spread across the galaxies. He raised first question ‘are we alone in the cosmic eternity” Or life also existed in extraterrestrial planets or atmosphere or in asteroids where from it came through a rocket system, our heavenly mom late Mrs Bani Bhattacharya, of 7/51 Purbapalli, sodepur, 24 Parganas(north) Kol-110,west Bengal, used to tell our brothers and sister in our child hood such peculiar stories? She had auditory hallucination. She had a false belief of Panspermia? People from extra terrestrial of other galaxies,other planets used to tell her various stories or used to speak with her. Really civilized life also exist in extraterrestrial planets or atmosphere or other universe? If it was so, on the countless other planets that may circle other sun, in same distances from their sun, as our earth circle our sun in a distance, life may exist. It may exist as organic molecule like carbon molecule based life, as life on our earth [then there the evolutionary pattern would be same as it happened in our earth] or they may be different. Based on other molecule (say silica based, Iron based, sulpher based) with other type of evolutionary system and adaptation to their environment. Francis Crick, the Nobel Laureate for discovering the double Helix structure of DNA molecule, once wrote ostensibly to answer “ Enrico Framis”- another Nobel laureate for his famous question “ …if there are intelligent beings in the galaxy why are they only in earth?” and Crick assessed the hypothesis known as “ Directed Panspermia hypothesis”, that is to say a variant of Arrethenious 19th century theory modified, in that Crick considered “whether life was deliberately planted in earth by some God?” i.e. evolution from extraterrestrial space?. Answer that Francis Crick gave to Enrico Framis “ ….that life on earth could well have originated elsewhere in the galaxy and that there had been time enough for intelligent beings to evolve elsewhere. A suitable environment and to have dissipated prokaryotic and Eukariotic microorganisms by rocket or asteroid to this planet where life may have developed” Crick however admitted that the theory of “Directed Panspermia” although suffered from possible paucity of evidences.
In the great darkness of Space Time, between stars there are Condensed Dark Matter(composed of gas, dusts, organic matter) with dozens of different kinds of organic molecules. The abundance of these molecules further suggests that stuff of life is everywhere in the cosmos. The possibility of life is on some of thousands of planets in our Milky Way galaxy even or in other galaxies of universe or may be in other universes if there are multi universes as per string theory. Life may never arose some where, on the other hand it may arose and died and or never evolved beyond the simplest form or in some planets there may be life which developed more intelligent civilization, more advanced then human civilization on the surface of earth. The biologists and physicists say that our planet “the Earth” is perfectly suitable one for evolution now. Moderate temperature, liquid water, Oxygen, Nitrogen in air, green house effect and so on were helpful for development of life here. We the earthlings are supremely well adapted to this environment, because we grew up here in three-dimensional form from three-dimensional molecule very complex organic molecule DNA/RNA in three dimensional-time on this earth.
In the beginning of our universe, many says there was the Big Bang, and only physics, the mostly and yet undiscovered laws of universe. Then chemistry came along at milder temperatures; when elementary particles quarks with its color ultimately formed nucleons and then atoms; These united to give more and more complex organic molecules ever most complex largest molecule on earth the RNA, DNA, enzymes, genes, epegenes which in turn associated into organized aggregates and membranes, defining the most primitive cells out of which life emerged in this planet. CHEMISTRY may be then considered is the science of matter and of its transformations, and LIFE in this planet is its highest form of expression of chemistry. Chemistry and notably supra molecular chemistry thus entertained a double relationship with biology of life in this planet. The progression from elementary particles to the nucleus, the atom, the molecule, the super molecule RNA and the supra molecular assembly of bio organic represents steps up the ladder of supra intelligence complexity that happened here. Particles interacted to form atoms, atoms to form molecules, molecules to form super molecules and supra molecular assemblies, etc. At each level a novel features appeared that however did not exist at a lower one. Thus a major line of development of chemistry to form life is towards more and more complex systems and the emergence of complexity. The highest level of complexity is that expressed in that highest form of matter, living matter, life, which itself culminated in the human brain, the plasticity of the neural system, epigenesis, consciousness and thought. For this what took the active role is the Darwinian evolutions that might also be brought into parallel with the recent development, via procedures of both chemical synthesis and molecular biology, of molecular diversity methods that combined the generation of large repertoires of molecules with highly efficient various selection procedures , adaptations, conflicts, to obtain products presenting specific properties the techniques of amplification by replication used in these methods would bear relation to the spontaneous generation of the target superstructures by the operation of self processes.
.A further major development along these lines, concerns the design of molecular species displaying the ability to form by self-replication.
With respect to the frontiers of life itself arises three basic questions to my mind which may be today asked: How it appeared in cosmos? Where are places it appeared? Why it appeared?
The first concerns the origin of life on this planet the earth only as we know it, of our biological world. But is it trues only this planet? The second considers the possibility of extraterrestrial life, within or beyond the solar systems, beyond galaxies, or beyond even our universe. The third question wonders why life has taken the forms we know; it has as corollary the question whether other forms of life can (and do) exist: is there “artificial life”?; it also implies that one might try to set the stage and implement the steps that would allow, in a distant future, the creation of artificial forms of life. Such an enterprise, which one cannot (and should not) at the present stage outline in detail except for initial steps, rests on the presupposition that there may be more than one, several expressions of the processes characterizing life. It thus invites to the exploration of the “frontiers of other lifes” and of the chemical evolution of living worlds.
Questions have been addressed about which one may speculate, let one’s imagination wander, perhaps even set paths for future investigations. However, where the answers lie is not clear at present and future chemical research towards ever more complex systems will uncover new modes of thinking and new ways of acting that we at present do not know about and may even be unable to imagine.
An excess of L-amino acids was detected in Murchison and Murray, two meteorites of the carbonaceous chondrite class ,although some discrepancies in the reported results remain to be yet resolved. Cronin et al. (1) originally discarded the evidence for small excesses of L-enantiomers in Murchison as controversial and possibly caused by terrestrial contamination. Later, however, they themselves found an enantiomeric excess of various amino acids that have never been reported, or are of limited occurrence, on Earth (2,3). The detection of a significant 15N enrichment in individual amino acid enantiomers from Murchison, when was compared with their terrestrial counterparts, it confirmed that the source of these amino acids was extraterrestrial and not any terrestrial contamination. Carbonaceous chondrites formed ~4.5 billion years ago (i.e., before the origin of life on Earth). There is still some controversy regarding the actual origin of those meteoritic amino acids (i.e., on the meteorite parent body via Strecker synthesis in liquid water [1,4] or in the interstellar medium followed by incorporation into the parent body [2, 5]. Experiments with interstellar ice analogues have shown that the UV-light–induced synthesis of amino acids was possible under the types of conditions likely to be found in interstellar dust (5, 6). No matter which scenario is the correct one, the finding of an excess of L-amino acids in carbonaceous chondrites strongly suggests that the excess is of extraterrestrial origin and existed in the solar system before the origin of life on Earth.
The experiments further indicated that at least some amino acids do not undergo complete racemization during their residence in space, transit to Earth, atmospheric entry, and surface impact. The -methyl amino acids found to exhibit considerable excess of the L-enantiomer in the Murchison meteorite are reportedly quite resistant to racemization (2). Racemization half-lives of meteoritic -amino acids, the ones used for protein synthesis in contemporary terrestrial organisms, were calculated from models, taking into account the various environments that such an amino acid was exposed to in space (7). In the temperature range between 150 and 300K, the racemization half-lives varied between amino acids by approximately 5 orders of magnitude, with glutamic acid and iso-leucine predicted to retain an enantiomeric excess much longer than phenylalanine, aspartic acid, and alanine. These calculations suggested that the reported D/L value for glutamic acid in Murchison of 0.3 (8) was close to the original value, whereas that of alanine (D/L = 0.5) could correspond to original values in the range of 0.5 to 0.35 (7 ). Note, however, that others did not observe any enantiomeric excess in alanine (3 ). Other experiments suggested that amino acid racemization at high temperatures, as may be encountered during atmospheric entry and surface impacts of space bodies, would be very rapid (9 ). Incorporation into rocks of a size to prevent their being heating all the way through should, however, overcome this problem. The presence of a variety of amino acids in meteorites raises the further question of whether not only the source of enantiomeric excess in terrestrial amino acids but also possibly the provenance of pre-biotic amino acids themselves was extraterrestrial. Meteorites are actually considered unlikely to have made a significant contribution to the total amount of pre-biotic organics (10, ). In contrast, impacts of carbonaceous asteroids and comets during the period of heavy bombardment 4.5–3.8 billion years ago are thought to have been important sources not just of amino acids but also a variety of prebiotic organic molecules (11, 12). Even greater amounts of organic material are likely to have been accreted from interplanetary dust particles, which are currently contributing ~3.2 x 105 kg year-1 of intact organics. How large a portion of the total inventory of organics on early Earth came from extraterrestrial sources depends on a variety of factors, foremost among them the actual composition of Earth’s early atmosphere and hence the extent of endogenous production. Whereas Miller and Urey assumed a fully reducing early terrestrial atmosphere for their famous experiments, it is now thought that it was non reducing or slightly reducing (12–14). The efficiency of organic synthesis decreases rapidly as a function of the H2/CO2 ratio. It has been calculated that with UV light as the energy source, a yearly production of 2 x 1011 kg organics would have occurred in a reducing atmosphere, whereas only 3 x 108 kg year-1 would be produced in a neutral atmosphere (H2/CO2 = 0.1) (12). Recent experiments suggested that high-energy particles, but not UV light, were able to generate amino acid precursors under mildly reducing conditions (10). The delivery to Earth of large amounts of extraterrestrial carbonaceous compounds, including many of the building blocks of life, might actually fall under a new expanded definition of panspermia (15). Originally, however, the term panspermia referred to the transfer of some form of viable extraterrestrial organism. Theoretically, the transfer of such organisms between planets within our solar system is possible on rocks ejected by large impacts (16). A majority of these ejecta were heated to temperatures that would kill all microbes; however, some remain almost un shocked (17). Further heating during the ascent through the atmosphere of the home planet requires that the ejecta be of a size that prevents heating to 100°C all through, with a diameter of >0.2 m estimated as necessary. Similar heating occurs during the entry into and passage through the atmosphere of the target planet and the landing there. In between, microbes would have to survive thousands of years of travel through space. Space is a very hostile environment in which UV and ionizing radiation, extreme vacuum, and very cold temperatures individually, and even more so in combination, are potentially lethal (10). Theoretical and experimental results indicate, however, that protection from these sterilizing factors may be possible (10). The ability of some bacteria to form spores makes them attractive candidates for extraterrestrial organisms that might have introduced life to Earth (18). Spores represent a dormant state. This offers the advantage of the absence of (detectable) metabolism and high resistance to a variety of physical insults, including those imposed by prolonged space travel. Only a small proportion of spores were found to survive space travel of up to 6 years (i.e., a minute fraction of the actual time they may have to spend in space during transfer between planets [ 18]). A single living organism may be enough to seed life on another planet, however.
Panspermia theories offer the advantage of overcoming the difficulties arising from the shortness of the time interval during which life on Earth must have become established. Life could not have arisen, or would have been destroyed if it did, during the heavy bombardment period that ended about 3.8 Gyr ago. Microfossils and stromatolites indicate that life must have originated more than 3.5 Gyr ago, and evidence of biologically mediated carbon isotope fraction puts the existence of life back even farther, to ~3.8 Gyr ago. This leaves a very narrow window of time for the emergence of terrestrial life and adds some plausibility to scenarios in which a preformed extraterrestrial life form started life on Earth. Ultimately, however, postulating an extraterrestrial origin not just for organic bio molecules but for entire organisms simply shifts the location of the origin of life, without addressing the underlying questions of how life arose and at what point during this process homo chirality became established.
Clearly the questions of life’s origin and the relationship of its emergence to the phenomenon of homochirality are the subject of active investigation. To conclude this review, we are struck by the ‘‘symmetry’’ of some of the possible mechanisms linking these questions and the expressions of these in aspects of biology. Homochirality, a prerequisite of life’s emergence in some scientists’ view, might arise as a consequence of the roles played by cosmology (e.g., by cold dark matter and cold dark energy) and occur at the far edge of galaxies. The conjunction of these (the dark) with our increasing understanding of the processes that control nuclear fusion and supernovas in providing both the building blocks and the energy (the light) to drive life’s processes leads us to conclude with a quote alluding to the symmetry of light and dark. Thus the darkness bear its fruit, and prove itself
Life in other universes- possible with symmetry breaking!
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Copy Right- Copy Right of this comment in the Journal "Science News" belongs to Professor Pranab kumar Bhattacharya and his first degree relatives only as per copy right act & rules of Intellectual Property Right Rules 3D/107/1201 a,b/ RDF Copy Right rules/ SPARC copy Right rules-2006/ and Protect intellectual Property Right(PIP) copy right rules of USA-2012.Please do not Infringe and be enough careful for your own safety if you are not direct Blood relation to prof Pranab Kumar Bhattacharya . No person, No NGOS [ except the authors& first degree relatives] in the state of West Bengal or in any states of India or in any abroad countries are authorized to use this article, with any meaning full, scientific sentences or with scientific and meaning full words laid out in this article either in the class room/ or in mass teaching programme including CME or in any form what so ever it is with any content of this article or while in writing any book or for his/her personal/ home use, or collective works or for any future Research or implementation as a policy matter or,[ except the authors ]or by Xeroxing and distributing the article/ or by printing/saving/broadcasting the article from any website of internet services,displayed without proper copy right clearance from the authors or from his family members or future copy right owner by written forms.
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