ASTRONOMICAL ORIGINS OF LIFE STEPS TOWARDS PANSPERMIA PDF

Astronomical origins of life: steps towards panspermia /​ edited by F. Hoyle and N.C. Wickramasinghe. Also Titled. Astrophysics and space science. Astronomical origins of life: steps towards panspermia. Responsibility: edited by F. Hoyle and N.C. Wickramasinghe. Imprint: Dordrecht ; Boston: Kluwer. Panspermia is the hypothesis that life exists throughout the Universe, distributed by space dust, Panspermia studies concentrate not on how life began, but on the methods argues that the pre-biotic organic building-blocks of life originated in space, . In , mathematician Edward Belbruno and astronomers Amaya.

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Panspermia hypotheses propose for example that microscopic life-forms that can survive the effects of space such as extremophiles can become trapped in debris ejected into space after collisions between planets and small Solar System bodies that harbor life.

Some organisms may travel dormant for an extended amount of time before colliding randomly with other planets or intermingling with protoplanetary disks. Under certain ideal impact circumstances into a body of water, for exampleand ideal conditions on a new planet’s surfaces, it is possible that the surviving organisms could become active and begin to colonize their new environment.

Panspermia studies concentrate not on how life beganbut on the methods that may cause its distribution in the Universe. Pseudo-panspermia sometimes called “soft panspermia” or “molecular panspermia” argues that the pre-biotic organic building-blocks of life originated in space, became incorporated in the solar nebula from which planets condensed, and were further—and continuously—distributed to planetary surfaces where life then emerged abiogenesis.

Interstellar molecules are formed by chemical reactions within very sparse interstellar or circumstellar clouds of dust and gas. The chemistry leading to life may have begun shortly after the Big Bang, Though the presence of life is confirmed only on the Earth, some scientists think that extraterrestrial life is not only plausible, but probable or inevitable.

Probes and instruments have started examining other planets and moons in the Solar System and in other planetary systems for evidence of having once supported simple life, and projects such as SETI attempt to detect radio transmissions from possible extraterrestrial stteps. The first known mention of the term was in the writings of the panspemria BC Greek philosopher Anaxagoras.

Richter[19] Kelvin[20] Hermann von Helmholtz [21] [22] and finally reaching the level of a detailed scientific hypothesis through the efforts of the Swedish chemist Svante Arrhenius Fred Hoyle — and Chandra Wickramasinghe born were influential proponents of panspermia. In an Origins Symposium presentation on April 7,physicist Stephen Hawking stated his opinion about what humans may find when venturing into space, such as the possibility of alien life through the theory of panspermia: Three series of astrobiology experiments have been conducted outside the International Space Station between and EXPOSE where a wide variety of biomoleculesmicroorganisms, and their spores were exposed to the solar flux and vacuum of space for about pife.

Some organisms survived in an inactive state for considerable lengths of time, [31] [32] and those samples sheltered by simulated meteorite material provide experimental evidence for the likelihood of the hypothetical scenario of lithopanspermia.

Several simulations in laboratories and in low Earth orbit suggest that ejection, entry and impact is survivable for some simple organisms.

Inremains of biotic material were found in 4. In Aprila Russian team published a paper which disclosed that they found DNA on the exterior of the ISS from land and marine bacteria similar to those previously observed in superficial micro layers origina the Barents and Kara seas’ coastal zones. They conclude “The presence of the wild land and marine bacteria DNA on the ISS suggests their possible transfer from the stratosphere into the astronoical with the ascending branch of the global atmospheric electrical circuit.

Alternatively, the wild land and marine bacteria as well as the ISS bacteria may all have an ultimate space origin. In OctoberHarvard astronomers presented an analytical model that suggests matter—and potentially dormant spores —can be exchanged across the vast distances between galaxiesa process termed ‘galactic panspermia’, and not be restricted to the limited scale of solar od.

Panspermia can be said to be either interstellar between astronomiical systems or interplanetary between planets in the same star system ; [37] [38] its transport mechanisms may include comets[39] [40] prigins pressure and lithopanspermia microorganisms embedded in rocks. However, space agencies have implemented planetary protection procedures to reduce the risk of planetary contamination, [44] [45] although, as towsrds discovered, pannspermia microorganisms, such as Tersicoccus phoenicismay be resistant to procedures used in spacecraft assembly clean room facilities.

Astronomical Origins of Life: Steps Towards Panspermia – B. Hoyle – Google Books

InSvante Arrhenius published in his article The Distribution of Life in Space[55] the hypothesis now called radiopanspermia, that microscopic forms of life can be propagated in space, driven by the radiation pressure from stars. However, because its effectiveness decreases with increasing size of the particle, this mechanism holds for very tiny particles only, such as single bacterial spores. Based on experimental data on radiation effects and DNA stability, it has been concluded that for such long travel times, boulder-sized rocks which are oritins than or equal to 1 meter in diameter are required to effectively shield astrknomical microorganisms, such as bacterial spores ,ife galactic cosmic radiation.

Lithopanspermia, the transfer of organisms in rocks from one planet to another either through interplanetary or interstellar space, remains speculative. Although there is no evidence that lithopanspermia has occurred in the Solar System, the various stages have become if to experimental testing.

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Thomas Golda professor of astronomysuggested in the hypothesis of “Cosmic Garbage”, that life on Earth might have originated accidentally from a pile of waste products dumped on Earth long ago by extraterrestrial beings. Directed panspermia concerns the deliberate transport of microorganisms in space, sent to Earth to start life here, or sent from Earth to seed new planetary systems with life by introduced species of microorganisms on lifeless planets.

The Nobel prize winner Francis Crickalong with Leslie Orgel proposed that life may have been purposely spread by an advanced extraterrestrial civilization, [48] but considering an early ” RNA world ” Crick noted later that life may have originated on Earth. Conversely, active directed panspermia has been proposed astronomicap secure and expand life in space. These young targets, where local life would not have formed yet, avoid kife interference with local life.

For example, microbial payloads launched by solar sails at speeds up to 0. Fleets origibs microbial capsules can be aimed at clusters of new stars in pqnspermia clouds, where they may land on planets or be captured by asteroids and comets and later delivered to planets. Payloads may contain extremophiles for diverse environments and cyanobacteria similar to early microorganisms.

Hardy multicellular organisms rotifer cysts may be included to induce higher evolution. These calculations show that relatively near target stars Alpha PsA, Beta Pictoris can be seeded by milligrams of launched microbes; while seeding the Rho Ophiochus star-forming cloud requires hundreds of kilograms of dispersed capsules. Directed panspermia to secure and expand life in space ssteps becoming possible because of developments in solar sailsprecise astrometryextrasolar planetsextremophiles and microbial genetic engineering.

A number of publications since have proposed the idea that directed panspermia could be demonstrated to be the origin of all life on Pansspermia if a distinctive ‘signature’ message were found, deliberately implanted into either the genome or the genetic code of the first microorganisms by our hypothetical progenitor.

In a team of physicists claimed that they had found mathematical and semiotic patterns in the genetic code which they think is evidence for such a signature. Their methods failed to recognize a well-known functional association in the genetic code; they did not rule out the operation of natural law before rushing to falsely infer design Nothing in the genetic code requires design.

In a later peer-reviewed article, the authors address the operation of natural law in an extensive statistical test, and draw the same conclusion as in the previous article. Pseudo-panspermia sometimes called soft panspermia, molecular panspermia or quasi-panspermia proposes that the organic molecules used for life originated in space and were incorporated in the solar nebula, from which the planets condensed and were further —and continuously— distributed to planetary surfaces where life then emerged abiogenesis.

The first suggestion came from Chandra Wickramasinghewho proposed a polymeric composition based on the molecule formaldehyde CH 2 O. Usually this occurs when a molecule becomes ionizedoften as the result of an interaction with cosmic rays. This positively charged molecule then draws in a nearby reactant by electrostatic attraction of the neutral molecule’s electrons.

Molecules can also be generated by reactions between neutral atoms and molecules, although this process is generally slower.

Biologically relevant molecules identified so far include uracilan RNA nucleobaseand xanthine. In AugustNASA scientists identified one of the fundamental chemical building-blocks of life the amino acid glycine in a comet for the first time.

In Augusta report, based on NASA studies with meteorites found on Earthwas published suggesting building blocks of DNA adenineguanine and related organic molecules may have been formed extraterrestrially in outer space. In Augustand in a world first, astronomers at Copenhagen University reported the detection of a specific sugar molecule, glycolaldehydein a distant star system.

The molecule was found around the protostellar binary IRASwhich is located light years from Earth. This finding suggests that complex organic molecules may form in stellar systems prior to the formation of planets, eventually arriving on young planets early in their formation. In SeptemberNASA scientists reported that polycyclic aromatic hydrocarbons PAHssubjected to interstellar medium ISM conditions, are transformed, through hydrogenationoxygenation and hydroxylationto more complex organics — “a step along the path toward amino acids and nucleotidesthe raw materials of proteins and DNArespectively”.

The chemicals, found in a giant cloud of gas about 25, light-years from Earth in ISM, may be a precursor to a key component of DNA and the other may have a role in the formation of an important amino acid. Researchers found a molecule called cyanomethanimine, which produces adenineone of the four nucleobases that form the “rungs” in the ladder-like structure of DNA.

The other molecule, called ethanamineis thought to play a role in forming alanineone of the twenty amino acids in the genetic code. Previously, scientists thought such processes took place in the very tenuous gas between the stars.

The new discoveries, however, suggest that the chemical formation sequences for these molecules occurred not in gas, but on the surfaces of ice grains in interstellar space. In Marcha simulation orignis indicate that dipeptides pairs of amino acids that can be building blocks astrojomical proteinscan be created in interstellar dust.

PAHs seem to have been formed shortly after the Big Bangare widespread throughout the universe, and are associated with new stars and exoplanets. In AstonomicalNASA scientists reported that, for the first time, complex DNA and RNA organic compounds of lifeincluding uracil pansperjia, cytosine and thyminehave been formed in the laboratory atronomical outer space astronomicl, using starting chemicals, such as pyrimidinefound in meteorites.

Pyrimidine, like polycyclic aromatic hydrocarbons PAHsthe most carbon-rich chemical found in the Universemay have been formed in red giants or in interstellar dust and gas clouds, according to the scientists. The chemistry of life may have begun shortly after the Big Bang It is generally agreed that the conditions required for the ttowards of intelligent life as we know it are probably exceedingly rare in the universe, while simultaneously noting that simple single-celled microorganisms may be more likely.

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The extrasolar planet results from the Kepler mission estimate — billion towardss, with over 3, as candidates or confirmed exoplanets. It is estimated that space travel over cosmic distances would take an incredibly long time to an outside observer, and with vast amounts of energy required.

However, there are reasons to hypothesize that faster-than-light interstellar space travel might be feasible. This has been explored by NASA scientists since at least Hoyle and Wickramasinghe have speculated that several outbreaks of illnesses on Earth are of extraterrestrial origins, including the flu pandemicand certain outbreaks of polio and mad cow disease.

For the flu pandemic they hypothesized that cometary dust brought the virus to Earth simultaneously at multiple locations—a view almost universally dismissed by experts on this pandemic. Hoyle also speculated that HIV came from outer space. The Lancet subsequently published three responses to this letter, showing that the hypothesis was not evidence-based, and casting doubts on the quality of the experiments referenced by Wickramasinghe in his letter.

A separate fragment of the Orgueil meteorite kept in a sealed glass jar since its discovery was found in to have a seed capsule embedded in it, whilst the original glassy layer on the outside remained undisturbed.

Despite great initial excitement, the seed was found to be that of a European Juncaceae or Rush plant that had been glued into the fragment and camouflaged using coal oife.

Astronomical origins of life : steps towards panspermia in SearchWorks catalog

The outer “fusion layer” was in fact glue. Whilst the perpetrator of this hoax is unknown, it is thought that they sought to influence the 19th century debate on spontaneous generation — rather than panspermia — by demonstrating the transformation of inorganic to biological matter.

Until the s, life was thought to depend on its access to sunlight. Even life in the ocean depths, where sunlight cannot reach, was believed to obtain its nourishment either from consuming organic detritus rained down from the surface waters or from eating animals that did. This chemosynthesis revolutionized the study of biology by revealing that terrestrial life need not be Sun-dependent; it only requires water and an energy gradient in order to exist.

It is now known that extremophilesmicroorganisms with extraordinary capability to thrive in the harshest environments on Earth, can specialize to thrive in the deep-sea, [] [] [] ice, boiling water, acid, the water core of nuclear reactors, salt crystals, toxic waste and in a range of other extreme habitats that were previously thought to be inhospitable for life. In order to test some these towarcs potential resilience in outer space, plant seeds and spores of bacteriafungi and ferns have been exposed to the harsh space environment.

These structures may be highly og to ultraviolet and gamma radiationdesiccationlysozymetoqardsstarvation and chemical disinfectantswhile metabolically inactive. Spores germinate when favourable conditions are restored after exposure to conditions fatal to the parent organism.

The discovery of deep-sea ecosystemsalong with advancements in the fields of astrobiologyobservational astronomy and discovery of large varieties of extremophiles, opened up a new avenue in astrobiology by massively expanding the number of possible extraterrestrial habitats and possible transport of hardy microbial life through vast distances.

The question of whether certain microorganisms can survive in the harsh environment of outer space has intrigued biologists since the beginning of spaceflight, and opportunities were provided to expose samples to space. The first American tests were made induring the Gemini IX and XII missions, when samples of bacteriophage T1 and spores of Penicillium roqueforti were exposed to outer space for Thus, the plausibility of panspermia can be evaluated by examining life forms on Earth for their capacity to survive in space.

After the approximately month mission, their responses were studied in terms of survival, mutagenesis in the his B. The data were compared with those of a simultaneously running ground control experiment: Experiments developed for BIOPAN are designed to investigate the effect of the space environment on biological material after exposure between 13 and 17 days.

Of the 6 missions flown so far on BIOPAN between anddozens of experiments were conducted, and some analyzed the likelihood of panspermia. Some bacteria, lichens Xanthoria elegansRhizocarpon geographicum and their mycobiont cultures, the black Antarctic microfungi Cryomyces minteri and Cryomyces antarcticusspores, and even one animal tardigrades were found to have survived the harsh outer space environment and cosmic radiation.

If shielded against solar UVspores of B.

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The data support the likelihood of interplanetary transfer of microorganisms within meteorites, the so-called lithopanspermia hypothesis. Stpes from the orbital missions, especially the experiments SEEDS [] and LiFE[] concluded that after an month exposure, some seeds and lichens Stichococcus sp. The Tanpopo mission is an orbital astrobiology experiment by Japan that is currently investigating the possible interplanetary transfer of life, organic compoundsand possible terrestrial particles in low Earth orbit.