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Panspermia (Gk. πάς/πάν (pas/pan, all) σπέρμα (sperma, seed)) is the hypothesis that "seeds" of life exist already all over the Universe, that life on Earth may have originated through these "seeds", and that they may deliver or have delivered life to other habitable bodies. Greek ( IPA: or simply IPA: — Hellenic) has a documented history of 3,500 years, the longest of any single natural language in the Indo-European language family. ...
Look up Hypothesis in Wiktionary, the free dictionary. ...
This article is about life in general. ...
For other uses, see Universe (disambiguation). ...
This article is about the tv programme Life on Earth. ...
Exogenesis (Gk. "outside origin") is a more limited hypothesis that proposes life on Earth was transferred from elsewhere in the Universe but makes no prediction about how widespread it is. Because the term "panspermia" is more well-known, it tends to be used in reference to what would properly be called exogenesis. Greek ( IPA: or simply IPA: — Hellenic) has a documented history of 3,500 years, the longest of any single natural language in the Indo-European language family. ...
The hypothesis is notable as a topic in science-fiction and quasi-religious circles such as Raëlism.[citation needed] For the song from The Rocky Horror Show, see Science Fiction/Double Feature. ...
A gathering of Raëlians in South Korea Raëlism is an UFO religion that is known by the names of Raëlian Church, MADECH from 1974 to 1976,[1] and International Raëlian Movement afterwards. ...
Hypothesis The first known mention of the idea was in the writings of the 5th century BC Greek philosopher Anaxagoras.[citation needed] The panspermia hypothesis was dormant until 1743 when it appeared posthumously in the writings of Benoît de Maillet, who suggested that germs from space had fallen into the oceans and grown into fish and later amphibians, reptiles and then mammals. In the nineteenth century it was again revived in modern form by several scientists, including Jöns Jacob Berzelius (1834),[1] Kelvin (1871),[2] Hermann von Helmholtz (1879) and, somewhat later, by Svante Arrhenius (1903). Panspermia can be said to be either interstellar (between star systems) or interplanetary (between planets in the same star system). Mechanisms for panspermia include radiation pressure (Arrhenius), lithopanspermia (microorganisms in rocks) (Kelvin).[3][4] Directed panspermia from space to seed Earth (Orgel and Crick, 1973)[5] or sent from Earth to seed other solar systems (Mautner 1979, 1997)[6][7] has also been proposed. The 5th century BC started the first day of 500 BC and ended the last day of 401 BC. // The Parthenon of Athens seen from the hill of the Pnyx to the west. ...
Anaxagoras Anaxagoras (Greek: ΑναξαγόÏας, c. ...
Benoît de Maillet, from Description de lÉgypte Paris, 1735. ...
For other uses, see Fish (disambiguation). ...
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Reptilia redirects here. ...
Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ...
Jöns Jakob Berzelius Statue of Berzelius in the centre of Berzelii Park, Stockholm Jöns Jakob Berzelius (August 20, 1779 - August 7, 1848) was a Swedish chemist. ...
For other persons named William Thomson, see William Thomson (disambiguation). ...
Hermann Ludwig Ferdinand von Helmholtz (August 31, 1821 – September 8, 1894) was a German physician and physicist. ...
Svante August Arrhenius (February 19, 1859 – October 2, 1927) was a Swedish chemist and one of the founders of the science of physical chemistry. ...
There is as yet no compelling evidence to support or contradict it, although the majority view holds that panspermia — especially in its interstellar form — is unlikely given the challenges of survival and transport in space. One new twist to the theory by engineer Thomas Dehel (2006) proposes that plasmoids ejected from the magnetosphere may move the few spores lifted from the Earth's atmosphere with sufficient speed to cross interstellar space to other systems before the spores can be destroyed. [8] [9]
Sir Fred Hoyle (1915–2001) and Chandra Wickramasinghe (born 1939) were important proponents of the hypothesis who further contended that lifeforms continue to enter the Earth's atmosphere, and may be responsible for epidemic outbreaks, new diseases, and the genetic novelty necessary for macroevolution. This extension has also been adopted by proponents of Cosmic ancestry. Sir Fred Hoyle (June 24, 1915 – August 20, 2001) was a British astronomer, notable for a number of his theories that run counter to current astronomical opinion, and a writer of science fiction, including a number of books co-authored by his son Geoffrey Hoyle. ...
Nalin Chandra Wickramasinghe (1939-) is professor of Applied Mathematics and Astronomy at Cardiff University; Director of Cardiff Centre for Astrobiology. ...
Macroevolution refers to evolution that occurs at or above the level of species, in contrast with microevolution, which refers to smaller evolutionary changes (typically described as changes in allele frequencies) within a species or population. ...
An extreme form of panspermia proposed by Brig Klyce the hypothesis states: Intelligent life is neither the product of supernatural creation nor was it spontaneously generation through abiogenesis (the Origin of Life) but has always existed in the universe. ...
Panspermia per se does not remove the need for life to originate somewhere, but does extend the time frame and environments available. Similarly, it does not necessarily suggest that life originated only once and subsequently spread through the entire Universe, but instead that once started it may be able to spread to other environments suitable for replication. (In the strongest version of panspermia, life never originated, but always existed — this axiom would require amending the big bang theory.) The mechanisms proposed for interstellar panspermia are hypothetical and currently unproven. Interplanetary transfer of material is well documented, as evidenced by meteorites of Martian origin found on Earth. However, claims that these carry evidence of extraterrestrial lifeforms — let alone viable dormant lifeforms — have either been proven unfounded as a result of terrestrial contamination, misinterpretation, or hoaxing; or are currently hotly disputed.[citation needed] For other uses, see Big Bang (disambiguation). ...
A Martian meteorite is a meteorite, that has landed on Earth but is believed to have originated from Mars. ...
Interestingly, space probes may also be a viable transport mechanism for interplanetary cross-pollination in our solar system (or even beyond). However, NASA has implemented strict abiotic procedures to avoid planetary contamination. Italic textBold text Technicians work on the Ulysses space probe. ...
Evidence Until a large portion of the galaxy is surveyed for signs of life or contact is made with other civilizations, the panspermia hypothesis in its fullest meaning will remain difficult to test. There is, however, circumstantial evidence for exogenesis: Circumstantial evidence is lesbian sex with a huge glass dildo unrelated facts that, when considered together, can be used to infer a conclusion about something unknown. ...
Narrow time window for geogenesis The Precambrian fossil record indicates that life appeared soon after the Earth was formed. This would imply that life appears in several hundred million years when conditions are favourable. |Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park File links The following pages link to this file: Evolution Origin of life Panspermia Stromatolite ...
|Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park File links The following pages link to this file: Evolution Origin of life Panspermia Stromatolite ...
The Precambrian or Cryptozoic is the period of the geologic timescale from the formation of Earth around 4500 million years before the present (BP) to the evolution of abundant macroscopic hard-shelled fossils, which marked the beginning of the Cambrian, some 542 million years BP. Remarkably little is known about...
Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park. ...
For the non-adjoining national park by the same name in British Columbia, see Glacier National Park (Canada). ...
For other uses of the term, see Fossil (disambiguation) Fossils are the mineralized remains of animals or plants or other artifacts such as footprints. ...
Osborne (talk) 20:17, 5 December 2007 (UTC):For the programming language, see algae (programming language) Laurencia, a marine red alga from Hawaii. ...
The Precambrian (Pre-Cambrian) is an informal name for the supereon comprising the eons of the geologic timescale that came before the current Phanerozoic eon. ...
For other uses, see Fossil (disambiguation). ...
- Generally accepted scientific estimates of the age of the Earth place its formation (along with the rest of the Solar system) at about 4.55 Ga.
- The oldest known sedimentary rocks are somewhat altered Hadean formations from the southern tip of Akilia island, West Greenland. These rocks have been dated as no younger than 3.85 Ga. The Greenland sediments include banded iron beds, thought to be the result of oxygen released by photosynthetic organisms combining with dissolved iron to form insoluble iron oxides. Carbon deposits in the rock show low levels of carbon-13. Kerogen deposits (derived from organic matter) are isotopically light (i.e. more negative δ13C values) which is indicative of photosynthesis (see Schidlowski, 1988). However, this interpretation is under doubt as the Akilia rocks have undergone high-temperature metamorphosis which is known to be fractionating itself (Gilmour & Wright, 1997). There is also a lack of corroborating sulphur isotope fractionation (Nisbet, 2000). Both the sedimentary origin and the carbon content of the rocks have been questioned (Lepland et al, 2005).
- Fossilized stromatolites or bacterial aggregates, the oldest of which are dated at 3.5 billion years old, suggest that photosynthesis might be exogenic. The bacteria that form stromatolites, cyanobacteria, are photosynthetic. Most models of the origin of life have the earliest organisms obtaining energy from reduced chemicals, with the more complex mechanisms of photosynthesis evolving later.
- During the Late Heavy Bombardment of the Earth's Moon about 3.9 Ga (as evidenced by Apollo lunar samples) impact intensities may have been up to 100x those immediately before or after (Cohen et al., 2000). From analysis of lunar melts and observations of similar cratering on Mars' highlands, Kring and Cohen (2002) suggest that the LHB was caused by asteroid impacts that affected the entire inner solar system. This is likely to have effectively sterilised Earth's entire planetary surface, including submarine hydrothermal systems that would be otherwise protected (Cohen et al., 2000).
- The best estimate of the origin of the Universe, from the Wilkinson Microwave Anisotropy Probe, is 13700 million years ago (13.7 Ga). However, at least one subsequent cycle of star birth/death is required for nucleosynthesis of the C, N and O essential to life, and this process may have taken up to several Ga to produce sufficient quantities (Gilmour et al., 1997). This puts the earliest possible emergence of life in the Universe at ~12.7 Ga, although there is large uncertainty in the length of the necessary time period.
If life originated on Earth it did so in a window of at most 1 Ga (4.55 Ga to 3.5 Ga), most plausibly 400 Ma (3.9 Ga to 3.5 Ga), and possibly <100 Ma (3.9 Ga to 3.85 Ga) if the Greenland (3.85 Ga) isotope signal is correct. If life originated elsewhere, the window expands to ~9 Ga. That full length of time might not be available on a single planet, but the Earth has provided a life-friendly environment for at least 3.5 Ga. Earth as seen from Apollo 17 Modern geologists consider the age of the Earth to be around 4. ...
This article is about the Solar System. ...
Giga-annum, usually abbreviated as Ga, is a unit of time equal to 10^9 years. ...
Two types of sedimentary rock: limey shale overlain by limestone. ...
The name Hadean refers to the geologic period before 3800 million years ago (mya). ...
Akilia island is in West Greenland, about 22 kilometers south of Nuuk (Godthab), at 63. ...
Leaf. ...
Carbon-13 is a stable isotope of carbon. ...
Kerogens are chemical compounds that make up a portion of the organic matter in sedimentary rocks. ...
Stable isotopes are chemical isotopes that are not radioactive. ...
Photosynthesis splits water to liberate O2 and fixes CO2 into sugar The leaf is the primary site of photosynthesis in plants. ...
Quartzite, a form of metamorphic rock, from the Museum of Geology at University of Tartu collection. ...
There are three types of isotope fractionation: equilibrium fractionation kinetic fractionation mass-independent fractionation Categories: Physics stubs ...
This article is about the chemical element. ...
Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park. ...
Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ...
Orders The taxonomy is currently under revision. ...
For the definition, see Life. ...
In ring theory, a ring R is said to be reduced if it has no non-zero nilpotent elements. ...
The Late Heavy Bombardment (LHB) was a period approximately 3. ...
This article is about Earths moon. ...
Project Apollo was a series of human spaceflight missions undertaken by the United States of America (NASA) using the Apollo spacecraft and Saturn launch vehicle, conducted during the years 1961 – 1975. ...
Adjectives: Martian Atmosphere Surface pressure: 0. ...
For other uses, see Asteroid (disambiguation). ...
This article is about the Solar System. ...
A hydrothermal vent A hydrothermal vent is a fissure in a planets surface from which geothermally heated water issues. ...
Artist depiction of the WMAP satellite at the L2 point The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite whose mission is to survey the sky to measure the temperature of the radiant heat left over from the Big Bang. ...
Cross section of a red giant showing nucleosynthesis and elements formed Stellar nucleosynthesis is the collective term for the nuclear reactions taking place in stars to build the nuclei of the heavier elements. ...
For other uses, see Carbon (disambiguation). ...
General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ...
This article is about the chemical element and its most stable form, or dioxygen. ...
Extremophiles Evidence has accumulated that some bacteria and archaea are more resistant to extreme conditions than previously recognized, and may be able to survive for very long periods of time even in deep space. These extremophiles could possibly travel in a dormant state between environments suitable for ongoing life such as planetary surfaces. Phyla Crenarchaeota Euryarchaeota Korarchaeota Nanoarchaeota ARMAN The Archaea (pronounced ) are a group of prokaryotic and single-celled microorganisms. ...
An extremophile is an organism, usually unicellular, which thrives in or requires extreme conditions that would exceed optimal conditions for growth and reproduction in the majority of mesophilic terrestrial organisms. ...
- Bacteria and more complex organisms have been found in more extreme environments than thought possible, such as black smokers or oceanic volcanic vents. Some extremophile bacteria have been found living at temperatures above 100 °C; A study revealed that a fraction of bacteria survive heating pulses up to 250 degrees C in vacuum, while similar heating at normal atmospheric pressure leads to the total sterilization of samples.[10] Other bacteria can thrive in strongly caustic environments, and others at extreme pressures 11 km under the ocean.[11]
- Semi-dormant bacteria found in ice cores over a mile beneath the Antarctic lends credibility to the idea that the components of life might survive on the surface of icy comets.
- There are bacteria that do not rely on photosynthesis for energy. In particular, endolithic bacteria using chemosynthesis have been found inside rocks and in subterranean lakes.
- Deinococcus radiodurans is a radioresistant bacterium that can survive high radiation levels.
- Dormant bacteria have been isolated from insects in amber 10s Ma old.[12]
- Recent experiments suggest that if bacteria were somehow sheltered from the radiation of space, perhaps inside a thick meteoroid, they could survive dormant for millions of years.
- Duplicating the harsh conditions of cold interstellar space in their laboratory, NASA scientists have created primitive cells that mimic the membranous structures found in all living things. These chemical compounds may have played a part in the origin of life.[13]
A black smoker in the Atlantic Ocean Black smokers are a type of hydrothermal vent found on the ocean floor. ...
For other uses, see Celsius (disambiguation). ...
Causticity is, in chemistry, the property of a substance that causes corrosion, the deterioration of a material. ...
Ice Core sample taken from drill. ...
Greek ἀνταρκτικός, opposite the arctic) is a continent surrounding the Earths South Pole. ...
Endolith lifeform found inside an Antarctic rock An endolith or cryptoendolith is an organism (archaea, bacterium, or fungus) that lives inside rock, coral, animal shells, or in the pores between mineral grains. ...
Chemosynthesis is the biological conversion of 1 or more carbon molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic molecules (e. ...
Binomial name Brooks & Murray, 1981 Deinococcus radiodurans (strange berry that withstands radiation, formerly called Micrococcus radiodurans) is an extremophilic bacterium, and is the most radioresistant organism known. ...
Radioresistant organisms are capable of living in environments with very high levels of ionizing radiation, such as nuclear power plants. ...
Spores Spores are another potential vector for transporting life through inhospitable and inimical environments, such as the depths of interstellar space. Spores are produced as part of the normal life cycle of many plants, algae, fungi and some protozoans,[14] and some bacteria produce endospores or cysts during times of stress. These structures may be highly resilient while metabolically inactive, and some can function when favorable conditions are restored after exposure to radiation, temperature extremes, dessication, or other conditions fatal to the parent organism. The term spore has several different meanings in biology. ...
For other uses, see Plant (disambiguation). ...
Osborne (talk) 20:17, 5 December 2007 (UTC):For the programming language, see algae (programming language) Laurencia, a marine red alga from Hawaii. ...
For the fictional character, see Fungus the Bogeyman. ...
Protozoa (in Greek protos = first and zoon = animal) are single-celled creatures with nuclei that show some characteristics usually associated with animals, most notably mobility and heterotrophy. ...
An endospore is a dormant, tough, non-reproductive structure produced by a small number of bacteria from the Firmicute family. ...
Wider range of potential habitats for life Another line of evidence comes from research that shows there are many more potential habitats for life than Earth-like planets. - The presence of past liquid water on Mars, suggested by river-like formations on the red planet, was confirmed by the Mars Exploration Rover missions. In December of 2006, Michael C. Malin of Malin Space Science Systems published a paper in the journal Science which argued that his camera (the Mars Observer Camera) had found evidence suggesting water was occasionally flowing on the surface of Mars within the last five years.
- Water oceans might exist on Europa, Enceladus, Triton and perhaps other moons in the Solar system. Even moons that are now frozen ice balls might earlier have been melted internally by heat from radioactive rocky cores. Bodies like this may be extremely common throughout the Universe. Lake Vostok in Antarctica, which has been sealed for millions of years, and which may contain unusual life or be sterile, is a possible testing ground for ways to explore these moons.
- Bacteria have been discovered living within warm rock deep in the Earth's crust.
Artists Concept of Rover on Mars (credit: Maas Digital LLC) Marvin the Martian, Spirit rover Mission patch Duck Dodgers, Opportunity rover Mission patch NASAs Mars Exploration Rover (MER) Mission is an ongoing robotic mission of exploring Mars, that began in 2003 with the sending of two rovers — Spirit...
Michael C. Malin (born 1950) is an American astronomer, space-scientist, and CEO of Malin Space Science Systems. ...
Malin Space Science Systems is a San Diego, California company that designs, develops, and operates instruments to fly on unmanned spacecraft. ...
Science is the academic journal of the American Association for the Advancement of Science and is considered one of the worlds most prestigious scientific journals. ...
Apparent magnitude: 5. ...
Apparent magnitude 11. ...
Triton (trye-tÉ™n, IPA: , Greek ΤÏίτων), or Neptune I, is the planet Neptunes largest moon. ...
Lake Vostoks location within Antarctica (NASA) Lake Vostok is the largest of more than 70 subglacial lakes in Antarctica. ...
Evidence of extraterrestrial life The majority view in the scientific community seems to be an acceptance that the existence of intelligent life elsewhere in the Universe is highly probable due to the sheer number of potential sites where life could take hold.[citation needed] A small core of researchers continue to monitor the skies for transmissions from other stars, with the Search for Extra-Terrestrial Intelligence (SETI) project being the most popular example. This article is about the search for extra-terrestrial intelligence. ...
However, the special theory of relativity holds that travel over the vast distances between stars would be limited to the speed of light, and so take such a long time that many scientists think it unlikely that such travel would be practical for life forms as we know them. Despite this, over the past century thousands of people have reported UFO sightings in countries all over the world. These reports have caused disagreements among experts as to their validity,[15] and no undisputed evidence has ever been published in a mainstream scientific journal to suggest that intelligent alien species have visited the Earth. Special relativity (SR) or the special theory of relativity is the physical theory published in 1905 by Albert Einstein. ...
UFO can mean: Unidentified flying object United Future Organization, a Japanese-Brazilian electronic jazz band UFO, the rock band that previously featured Michael Schenker UFO, the Gerry Anderson TV series United Farmers of Ontario, a political party that formed the government in Ontario from 1919 to 1923 U.F.O...
Still under investigation/undetermined - The Red Rain of Kerala. In 2003, Satyanarayana et al. proposed that the rain was coloured red by a dust cloud from the Persian Gulf.[16] Their paper was then published in Aerosol Science and Technology.[17] Dr. Godfrey Louis has analyzed the dust and reported finding spores that he has hypothesised are of extraterrestrial origin. In April 2006, Louis published his findings in Astrophysics and Space Science.[18][19][20] Louis claimed that the red particles "reproduce plentifully", and that they did so even in "water superheated to nearly 300 °C".
 Microstructures in ALH84001 claimed to be of biogenic origin - A meteorite originating from Mars known as ALH84001 was shown in 1996 to contain microscopic structures resembling small terrestrial nanobacteria. When the discovery was announced, many immediately conjectured that the fossils were the first true evidence of extraterrestrial life — making headlines around the world, and even prompting U.S. President Bill Clinton to make a formal televised announcement to mark the event. As of 2003 however, most experts agree that these are not indicative of life, but may instead be formed abiotically from organic molecules. It has not yet conclusively been shown how they formed and recent advances in nanobe research has made the find interesting again.
- An Indian and British team of researchers led by Chandra Wickramasinghe reported evidence at the 46th annual meeting of the International Society for Optical Engineering (SPIE) in San Diego, California on April 29, 2001 that air samples gathered from the stratosphere by the Indian Space Research Organization contained clumps of living cells. Wickramsinghe calls this "unambiguous evidence for the presence of clumps of living cells in air samples from as high as 41 kilometers, well above the local tropopause, above which no air from lower down would normally be transported".[21] A reaction report at NASA Ames indicated skepticism towards the premise that Earth life cannot travel to and reside at such altitudes, but noted that some microbes can remain dormant for millions of years, possibly long enough for an interplanetary voyage.[22] Max Bernstein, a space scientist associated with SETI and Ames, argues the results should be interpreted with caution, noting that "it would strain one's credulity less to believe that terrestrial organisms had somehow been transported upwards than to assume that extraterrestrial organisms are falling inward".[21]
- On May, 2001, two researchers from the University of Naples claimed to have found live 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. They believe that the bacteria were not terrestrial because they survived when the sample was sterilized at very high temperature and washed with alcohol. They also claim that the bacteria's DNA is unlike any on Earth.[23] They presented a report on May 11, 2001, concluding that this is the first evidence of extraterrestrial life, documented in its genetic and morphological properties. Some of the bacteria they discovered were found inside meteorites that have been estimated to be over 4.5 billion years old, and were determined to be related to modern day Bacillus subtilis and Bacillus pumilus bacteria on Earth but appears to be a different strain.[24]
- Narlikar et al. (2003) took air samples at 41 km over Hyderabad, India — above the tropopause where mixing from the lower atmosphere is unexpected — from which rod and coccoid bacteria were isolated. Two bacterial and one fungal species were later independently isolated from these filters which were identified as Bacillus simplex, Staphylococcus pasteuri and Engyodontium album respectively (Wainwright, 2003).[25] The experimental procedure suggested that these were not the result of laboratory contamination, although similar isolation experiments at separate laboratories were unsuccessful. That these are common terrestrial organisms is not necessarily contraindicative of panspermia, since a prediction of the hypothesis is that life throughout the Universe is derived from the same ancestral stock. Assuming they are not contaminants, did the micro-organisms come from the Earth or space? That there were no volcanic eruptions — the only known way for terrestrial particles to mix up beyond the tropopause — prior to sampling suggests against a terrestrial source. In either case, Wainright (2003) points out that some part of the panspermia hypothesis is validated: either terrestrial micro-organisms are indeed derived from space, or they are capable of contaminating our local space in a viable form. Measuring the isotope ratios of carbon and nitrogen in the micro-organisms from the stratosphere could reveal whether they come from Earth or space.
- Of three biological experiments on the Mars lander Viking, two gave results that were initially indicative of life. However, the similar results from heated controls, how the release of indicative gas tapered off, and the lack of organic molecules in soil samples all suggest that the results were the result of an abiotic chemical reaction rather than biological metabolism. Later experiments showed that terrestrial clays could reproduce the results of the two positive Viking experiments. Despite this, some of the Viking experiments' designers remain convinced that they are diagnostic for life.
Red rain collected in buckets From 25 July to 23 September 2001, red rain sporadically descended upon the southern Indian state of Kerala. ...
A map showing countries commonly considered to be part of the Middle East The Middle East is a region comprising the lands around the southern and eastern parts of the Mediterranean Sea, a territory that extends from the eastern Mediterranean Sea to the Persian Gulf. ...
Dr. Godfrey Louis is a solid-state physicist at Mahatma Gandhi University, Kottayam. ...
Structures on ALH84001 meteorite Photo credit: NASA File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
Structures on ALH84001 meteorite Photo credit: NASA File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
Meteorite fragment ALH84001 ALH 84001 (Allan Hills 84001) is a meteorite found in Allan Hills, Antarctica in December 1984 by a team of US meteorite hunters from the ANSMET project. ...
Willamette Meteorite A meteorite is a natural object originating in outer space that survives an impact with the Earths surface without being destroyed. ...
Mars is the fourth planet from the Sun in the solar system, named after the Roman god of war (the counterpart of the Greek Ares), on account of its blood red color as viewed in the night sky. ...
Meteorite fragment ALH84001 ALH 84001 (Allan Hills 84001) is a meteorite found in Allan Hills, Antarctica in December 1984 by a team of US meteorite hunters from the ANSMET project. ...
A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ...
Structures found on meteorite fragment ALH84001 Nanobacteria (sometimes Nannobacteria ) are claimed to be cell-walled microorganisms with a diameter well below the generally accepted lower limit (about 0. ...
Green people redirects here. ...
Federal courts Supreme Court Circuit Courts of Appeal District Courts Elections Presidential elections Midterm elections Political Parties Democratic Republican Third parties State & Local government Governors Legislatures (List) State Courts Local Government Other countries Atlas US Government Portal For other uses, see President of the United States (disambiguation). ...
William Jefferson Bill Clinton (born William Jefferson Blythe III[1] on August 19, 1946) was the 42nd President of the United States, serving from 1993 to 2001. ...
An organic compound is any member of a large class of chemical compounds whose molecules contain carbon, with exception of carbides, carbonates, carbon oxides and gases containing carbon. ...
A nanobe Nanobes are tiny filamental structures first found in some rocks and sediments. ...
Aerial View of Moffett Field and NASA Ames Research Center. ...
This article is about the search for extra-terrestrial intelligence. ...
Giga-annum, usually abbreviated as Ga, is a unit of time equal to 10^9 years. ...
Binomial name Bacillus subtilis (Ehrenberg 1835) Cohn 1872 Gram-stained Bacillus subtilis Sporulating Bacillus subtilis Bacillus subtilis is a Gram-positive, catalase-positive bacterium commonly found in soil. ...
For other uses, see Hyderabad. ...
The tropopause is between the troposphere and the stratosphere. ...
This article is about volcanoes in geology. ...
The two Viking spacecraft each carried four biological experiments to the surface of Mars in the late 1970s. ...
Viking mission profile. ...
It has been suggested that this article or section be merged with scientific control. ...
For other uses, see Clay (disambiguation). ...
Mr Bound July 8, 2005 20:13 (UTC) Categories: Possible copyright violations ...
Surveyor 3 was the third lunar lander of the Surveyor program that explored the Moon. ...
Apollo 12 was the sixth manned mission in the Apollo program and the second to land on the Moon. ...
Falsified - In 1962, Claus et al. announced the discovery of 'organised elements' embedded in the Orgueil meteorite. These elements were subsequently shown to be either pollens (including that of ragwort) and fungal spores (Fitch & Anders, 1963) that had contaminated the sample, or crystals of the mineral olivine.
On May 14, 1864 the carbonaceous chondrite Orgueil meteorite landed near Orgueil in southern France. ...
SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ...
Species See text The Genus Senecio of the daisy family (Family Asteraceae) includes ragworts and groundsels. ...
For the fictional character, see Fungus the Bogeyman. ...
This article or section is in need of attention from an expert on the subject. ...
The mineral olivine (also called chrysolite and, when gem-quality, peridot) is a magnesium iron silicate with the formula (Mg,Fe)2SiO4. ...
For the plant, see Glycine (plant). ...
This article is about the class of chemicals. ...
“Space dust†redirects here. ...
Hoaxes - A separate fragment of the Orgueil meteorite (kept in a sealed glass jar since its discovery) was found in 1965 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 dust. The outer 'fusion layer' was in fact glue. Whilst the perpetrator of this hoax is unknown, it is thought he sought to influence the 19th century debate on spontaneous generation — rather than panspermia — by demonstrating the transformation of inorganic to biological matter.
On May 14, 1864 the carbonaceous chondrite Orgueil meteorite landed near Orgueil in southern France. ...
Genera Andesia Distichia Juncus - Rush Luzula - Woodrush Marsippospermum Oxychloë Prionium Rostkovia The Juncaceae, or the Rush Family, is a rather small monocot flowering plant family. ...
Coal dust is a fine powdered form of coal. ...
Abiogenesis, in its most general sense, is the hypothetical generation of life from non-living matter. ...
Objections to panspermia and exogenesis - Life as we know it requires heavy elements carbon, nitrogen and oxygen (C, N and O, respectively) to exist at sufficient densities and temperatures for the chemical reactions between them to occur. These conditions are not widespread in the Universe, so this limits the distribution of life as an ongoing process. First, the elements C, N and O are only created after at least one cycle of star birth/death: this is a limit to the earliest time life could have arisen. Second, densities of elements sufficient for the formation of more complex molecules necessary to life (such as amino acids) only occur in molecular dust clouds (109–1012 particles/m³), and (following their collapse) in solar systems. Third, temperatures must be lower than those in stars (elements are stripped of electrons: a plasma state) but higher than in interstellar space (reaction rates are too low). This restricts ongoing life to planetary environments where heavy elements are present at high densities, so long as temperatures are sufficient for plausible reaction rates. Note this does not restrict dormant forms of life to these environments, so this argument only contradicts the widest interpretation of panspermia — that life is ongoing and is spread across many different environments throughout the Universe — and presupposes that any life needs those elements, which the proponents of alternative biochemistries do not consider certain.
- Space is a damaging environment for life, as it would be exposed to radiation, cosmic rays and stellar winds. Studies of bacteria frozen in Antarctic glaciers have shown that DNA has a half-life of 1.1 million years under such conditions, suggesting that while life may have potentially moved around within the Solar System it is unlikely that it could have arrived from an interstellar source.[30] Environments may exist within meteorites or comets that are somewhat shielded from these hazards.
- Bacteria would not survive the immense heat and forces of an impact on Earth — no conclusions (whether positive or negative) have yet been reached on this point. However most of the heat generated when a meteor enters the Earth's atmosphere is carried away by ablation and the interiors of freshly landed meteorites are rarely heated much and are often cold. For example, a sample of hundreds of nematode worms on the space shuttle Columbia survived its crash landing from 63 km inside a 4 kg locker, and samples of already dead moss were not damaged. Though this is not a very good example, being protected by the man-made locker and possibly pieces of the shuttle, it lends some support to the idea that life could survive a trip through the atmosphere.[31] The existence of Martian meteorites and Lunar meteorites on Earth suggests that transfer of material from other planets to Earth happens regularly.
- Occam's Razor implies that when developing a hypothesis, we should avoid making evidentially unsupported presumptions about things if at all possible. See heuristic arguments. From this perspective, geogenesis appears to be the default assumption when compared with panspermia or exogenesis. The former assumes a single step: that life originated on Earth, where it is now commonly observed, excluding the presumption that life formed elsewhere, in places where it has never been observed before. Geogenesis eliminates the unsupported presumption of life existing beyond the Earth, but requires a lot to happen in a relatively short time frame in order for life to arise. Exogenesis assumes that it must require a longer period of time than could be offered on Earth. Given that an understanding of life's emergence remains speculative, however, the perception of which presumption (life beyond Earth or life emerging rapidly) is preferable can be less than clear, however.
- Supporters of exogenesis also argue that on a larger scale, for life to emerge in one place in the Universe and subsequently spread to other planets would be simpler than similar life emerging separately on different planets. Thus, finding any evidence of extraterrestrial life similar to ours would lend credibility to exogenesis. However, this again assumes that the emergence of life in the entire Universe is rare enough as to limit it to one or few events or origination sites. Exogenesis still requires life to have originated from somewhere, most probably some form of geogenesis. Given the immense expanse of the entire Universe, there is a higher probability that there exists (or has existed) another Earth-like planet that has yielded life (geogenesis) than not. This explanation is more preferred under Occam's Razor than exogenesis since it theorizes that the creation of life is a matter of probability and can occur when the correct conditions are met rather than in exogenesis that assumes it is a singular event or that Earth did not meet those conditions on its own. In other words, exogenesis theorizes only one or few origins of life in the Universe, whereas geogenesis theorizes that it is a matter of probability depending on the conditions of the celestial body. Consider that even the most rare events on Earth can happen multiple times and independent of one another. However, since to date no extraterrestrial life has been confirmed, both theories still suffer from lack of information and too many unidentified variables.
For other uses, see Carbon (disambiguation). ...
General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ...
This article is about the chemical element and its most stable form, or dioxygen. ...
For other uses, see Plasma. ...
Interstellar Space was one of the last albums recorded before the death of John Coltrane in 1967. ...
Alternative biochemistry is the speculative biochemistry of alien life forms that differ radically from those on Earth. ...
For other uses, see Radiation (disambiguation). ...
Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ...
A solar wind is a stream of particles (mostly high-energy protons ~ 500 keV) which are ejected from the upper atmosphere of a star (in the case of a star other than the Earths Sun, it may be called a stellar wind instead). ...
Perito Moreno Glacier Patagonia Argentina Aletsch Glacier, Switzerland Icebergs breaking off glaciers at Cape York, Greenland This article is about the geological formation. ...
Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ...
Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ...
Photo of a burst of meteors with extended exposure time A meteor is the visible path of a meteoroid that enters the Earths (or another bodys) atmosphere, commonly called a shooting star or falling star. ...
Ablation is defined as the removal of material from the surface of an object by vaporization, chipping, or other erosive processes. ...
Worlds second largest Meteorite in Culiacan, Mexico A meteorite is a relatively small extra-terrestrial body that reaches the Earths surface. ...
Classes Adenophorea Subclass Enoplia Subclass Chromadoria Secernentea Subclass Rhabditia Subclass Spiruria Subclass Diplogasteria Subclass Tylenchia The nematodes or roundworms (Phylum nematoda from Greek (nema): thread + -ode like) are one of the most common phyla of animals, with over 80,000 different described species (over 15,000 are parasitic). ...
Space Shuttle Columbia (NASA Orbiter Vehicle Designation: OV-102) was the first spaceworthy space shuttle in NASAs orbital fleet. ...
The mesosphere (from the Greek words mesos = middle and sphaira = ball) is the layer of the Earths atmosphere that is directly above the stratosphere and directly below the thermosphere. ...
A Martian meteorite is a meteorite that has landed on Earth but is believed to have originated from Mars. ...
Lunar Meteorite Allan Hills 81005 A Lunar meteorite is a meteorite that is known to have originated on the Moon. ...
For the House television show episode, see Occams Razor (House episode). ...
For other uses, see Heuristic (disambiguation). ...
Directed panspermia A second prominent proponent of panspermia was the late Nobel prize winner Professor Francis Crick, OM FRS, who along with Leslie Orgel proposed the theory of directed panspermia in 1973. This suggests that the seeds of life may have been purposely spread by an advanced extraterrestrial civilization. Crick argues that small grains containing DNA, or the building blocks of life, fired randomly in all directions is the best, most cost effective strategy for seeding life on a compatible planet at some time in the future. The strategy might have been pursued by a civilization facing catastrophic annihilation, or hoping to terraform planets for later colonization. Later, after biologists had proposed that an "RNA world" might be involved in the origin of life, Crick noted that he had been overly pessimistic about the chances of life originating on Earth.[32] See: Francis Crick. Francis Harry Compton Crick OM FRS (8 June 1916 – 28 July 2004), (Ph. ...
For other Orders see Order of Merit (disambiguation). ...
The Fellowship of the Royal Society was founded in 1660. ...
Leslie Eleazer Orgel (born Jan 12, 1927 in London) is a chemist. ...
Artists conception of a terraformed Mars in four stages of development. ...
The RNA world hypothesis proposes that RNA was, before the emergence of the first cell, the dominant, and probably the only, form of life. ...
Francis Harry Compton Crick OM FRS (8 June 1916 – 28 July 2004), (Ph. ...
Directed panspermia in reverse, from Earth to new solar systems, has been proposed to expand life in space.[33]For example, microbial payloads launched by solar sails at speeds up to 0.0001 c (30,000 m/s) would reach targets at 10 to 100 light-years in 0.1 million to 1 million years. Fleets of microbial capsules can be aimed at clusters of new stars in star-forming clouds where they may land on planets, or 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.[34]
The probability of hitting the target zone can be calculated from  where A(target) is the cross-section of the target area, dy is the positional uncertainty at arrival; a - constant (depending on units), r(target) is the radius of the target area; v the velocity of the probe; (tp) the targeting precision (arcsec/yr); and d the distance to the target (all units in SIU). Guided by high-resolution astrometry of 1×10−5 arcsec/yr, almost nearby 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.[35] The figure shows the launching of solar sail ships with effective thicknesses that will achieve final velocities as shown. The figure also shows the dispersion and capture of the microbial payload at the target solar system.
Directed panspermia is altruisitic and may be motivated by life-centered “panbiotic ethics” that aims to secure and propagate our form of gene/protein organic life, and to establish life as a controlling force in nature.
Theoretically, by humans traveling to other celestial bodies such as the moon, there is a chance that they carry with them microorganisms or other organic materials ubiquitous on Earth, thus raising the curious possibility that we can seed life on other planetary bodies. The same can be said for unmanned probes manufactured on Earth. This is a concern among space researchers who try to prevent Earth contamination from distorting data, especially in regards to finding possible extraterrestrial life. Even the best sterilization techniques can not guarantee that potentially invasive biologic or organic materials will not be unintentionally carried along. So far, however, in the limited amount of space exploration conducted by humans, "terrestrial pollution" does not appear to be a problem although no concrete studies have investigated this. The harsh environments encountered throughout the rest of the solar system so far do not seem to support complex terrestrial life. However, it should be noted that matter exchange in form of meteor impacts has existed and will exist in the solar system even without human intervention. As evidence, some argue that anomalies found within Martian meteorite ALH 84001 indicate that bacteria could travel from planet to planet without intelligent help. meteorite fragment ALH84001 ALH84001 (a contraction of Allen Hills 1984 #001) is a meteorite found in Allen Hills, Antarctica in December 1984 by a team of US meteorite hunters from the ANSMET project, among 7,000 others. ...
Deliberate directed panspermia would seed space objects. The securing of future life would need to balance against interference with science. This interference can be minimized by targeting remote solar systems where life would not have evolved yet. Seeding a few hundred young solar systems would secure future life while leaving billions of stars pristine for exploration.
There exists speculation on a connection to the Titius-Bode Law, arguing that Earth may have received seeds of life by directed panspermia, because the extraterrestrial senders knew that Earth belonged to a solar system with stable Titius-Bode structure. See: External Link "Directed Panspermia and Titius-Bode"
References in popular culture - Panspermia is in the X-Files episode "Bio-Genesis".
- In the opening sequence of Spore, a protein laden comet crashes to the player's planet, triggering life and the start of the cellular phase of game play.
- The opening of the animated music video for Pearl Jam's "Do the Evolution" features a comet crashing into a barren Earth, followed by scenes depicting simple organisms gradually evolving into more complex lifeforms.
- The novel The Gripping Hand by Larry Niven and Jerry Pournelle mentions that panspermia is a commonly accepted theory in that Universe. Niven also extensively writes about both directed and non-directed panspermia in his Known-Space novels.
- The film Panspermia by computer graphics artist Karl Sims features a world of complex and diverse species created by using "artificial evolution".[36] It has become one of the most influential works in the fields of both computer graphics and artificial life.[37] It was edited into the "Seeds of Life" segment of the computer graphics compilation Beyond the Mind's Eye.
- The film Evolution contains alien creatures who evolved from cells of life brought down from a meteorite.
- The musical group Panspermians[38] derives its name from the theory.
X-Files intro from first 8 seasons The X-Files was a popular 1990s American science fiction television series created by Chris Carter. ...
Spore is a multi-platform god game under development by Maxis and designed by Will Wright that allows a player to control the evolution of a species from its beginnings as a multicellular organism, through development as a sapient and social land-walking creature, to levels of interstellar exploration as...
This article is about the rock group. ...
Do the Evolution is a song by Pearl Jam, from the album Yield. ...
Dan Brown (born June 22, 1964) is an American author of thriller fiction, best known for the 2003 bestselling novel, The Da Vinci Code. ...
Deception Point book cover Deception Point (2001) is a thriller novel by Dan Brown, the author of The Da Vinci Code, Angels and Demons, and Digital Fortress. ...
Mission to Mars is a 2000 science fiction movie directed by Brian de Palma about a rescue mission to Mars following a disaster during the first manned voyage to the planet. ...
The Gripping Hand is a 1993 novel by Larry Niven and Jerry Pournelle. ...
This article does not cite any references or sources. ...
Jerry Eugene Pournelle, Ph. ...
Karl Sims is a researcher formerly with the MIT Media Lab who is most well known for using genetic programming to evolve virtual creatures that competed in various simulated environments as described in this paper. ...
The Minds Eye series consists of several art films rendered using computer-generated imagery of varying levels of sophistication, though it is far outstaged by the CGI used in recent movies such as the The Lord of the Rings adaptations, and even by the early examples in Jurassic Park. ...
Promotional poster for Evolution Evolution is a 2001 comedy sci-fi movie directed by Ivan Reitman. ...
Science fiction The theory of panspermia has been explored in a number of works of science fiction, notably Jack Finney's The Body Snatchers (four times made into a film) and the Dragonriders of Pern books of Anne McCaffrey. In John Wyndham's book, The Day of the Triffids (also made into a film), the first person narrator, writing in historical mode, takes care to reject the theory of panspermia in favour of the conclusion that the eponymous carnivorous plants are a product of Soviet biotechnology. The book and film of The Andromeda Strain examines the consequences of a pathogenic extraterrestrial organism arriving on Earth. Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ...
Jack Finney (October 2, 1911 - November 16, 1995) was an American author. ...
The Body Snatchers is a 1955 science fiction novel by Jack Finney, originally serialized in Colliers Magazine in 1954, which describes Earth being invaded by seeds which have drifted to Earth from space. ...
The Dragonriders of Pern is an extensive fantasy/science fiction series of novels and short stories primarily written by Anne McCaffrey. ...
Anne Inez McCaffrey (born April 1, 1926) is an American science fiction author best known for her Dragonriders of Pern series. ...
John Wyndham (July 10, 1903 – March 11, 1969) was the pen name used by the often post-apocalyptic British science fiction writer John Wyndham Parkes Lucas Beynon Harris. ...
The Day of the Triffids is a post-apocalyptic novel (categorised by author Brian Aldiss as a cosy catastrophe) written in 1951 by the English science fiction author John Wyndham. ...
An eponym is a person (real or fictitious) whose name has become identified with a particular object or activity. ...
CCCP redirects here. ...
The structure of insulin Biotechnology is technology based on biology, especially when used in agriculture, food science, and medicine. ...
This article is about the novel. ...
In contrast, Stephen Baxter's Titan suggests the possibility of geocentric panspermia: the astronaut's final dying act is to release bacteria into a Titanian lake. The theme is continued as the resultant beetle-like civilisation purposefully colonise new star systems. Stephen Baxter (born in Liverpool, 13 November 1957) is a British hard science fiction author. ...
Titan is a 1997 science fiction novel by Stephen Baxter. ...
Titan (, from Ancient Greek Τῑτάν) or Saturn VI is the largest moon of Saturn and the only moon known to have a dense atmosphere. ...
Some works of science fiction advance a derivative of the theory as a rationalization for the improbable tendency of fictional extraterrestrials to be strongly humanoid in form as well as living on earth-compatible worlds (see Class M planet) and having similar levels of technology. In a Star Trek: The Next Generation episode ("The Chase"), the humanoid aliens, which include the humans themselves, are results of the genetic codes spread through the Universe by the Ancient humanoids and were placed by the Ancient humanoids themselves. The Class M planet Earth. ...
The title as it appeared in most episodes opening credits. ...
The term humanoid refers to any being whose body structure resembles that of a human. ...
Ancient humanoids were a race of humanoids in the fictional Star Trek universe that were one of the universes oldest sentient species. ...
Recent Experiment After enduring a 12-day orbital mission and a fiery reentry, an unmanned spacecraft, Foton-M3, awaits retrieval in a field in Kazakhstan. The 5,500-pound capsule, seven-feet in diameter, housed experiments testing the lithopanspermia theory. The capsule contained, among other things, lichen that were exposed to the radiation of space. Scientists also strapped basalt and granite disks riddled with cyanobacteria to the capsule's heat shield to see if the microorganisms could survive the brutal conditions of reentry. Alas, this batch didn't arrive alive but the scientists believe that it was at a disadvantage. "When compared to a real meteorite," says Rene Demets, the European Space Agency's coordinator for space biological experiments for this mission, "the heat penetrates quite deeply into our test samples"[39] See also |
