ANYWHERE'S FINE: Kepler 20 f, with a diameter comparable to that of Earth, is one of the smallest known exoplanets.
Image: NASA/Ames/JPL-Caltech
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ANCHORAGE—In planet formation, slow, steady and small wins the race.
Astronomers using NASA's Kepler spacecraft have found that small planets such as Earth can form around all manner of stars, whereas massive gas giant planets like Jupiter tend to take shape around stars with large concentrations of heavy elements such as iron and oxygen.
The researchers published their findings online in Nature on June 13 and announced the results at the semiannual meeting of the American Astronomical Society being held here this week. (Scientific American is part of Nature Publishing Group.)
In the early years of exoplanetary science, beginning with the first discovery of a planet orbiting a sunlike star in 1995, the majority of known worlds outside of the solar system were giants much like Jupiter—and sometimes much more massive. Those heavyweights have the largest effects on their planetary systems and as such are the easiest to detect. Researchers noticed that the kinds of stars hosting giant planets tended to contain relatively high levels of so-called metals (an astronomer's term for any element heavier than hydrogen or helium.)
The chemical fingerprints of those stars point back to the makeup of the ancient disks of dust and gas from which the planets congealed, hinting that, at least for large worlds, having lots of metals around encourages planets to form. "If there's a lot of stuff in the disk, then we have a higher chance of finding these hot Jupiter planets," said lead study author Lars Buchhave of the Niels Bohr Institute at the University of Copenhagen.
The question was, do small planets—the Earth and Neptune analogues of the galaxy—follow the same trend? With the advent of modern planet-hunting instruments such as Kepler, a space telescope built to seek out Earth-size bodies, astronomers have finally gotten a peek at the smaller denizens of the planetary zoo.
Buchhave and his colleagues took spectral measurements of 152 stars that Kepler has inspected and where the spacecraft has projected the presence of 226 planets in total, most of them smaller in diameter than Neptune and some as small as Earth. (The mission has identified more than 2,000 probable planets altogether, but only dozens have been confirmed with follow-up observations.) They found that the host stars of those diminutive worlds are a diverse bunch, spanning a wide range of metallicities. On average, the small planets orbit stars roughly as metal-rich as the sun, a star of fairly ordinary composition, whereas giant exoplanets tend to inhabit planetary systems more enriched in metals.
That should not come as a total surprise, notes astronomer Andrew Howard of the University of California, Berkeley. After all, according to prevailing theoretical models, a giant planet acquires a solid core and then gathers gases and ices around that core to swell up to a Jupiter-like diameter. So that core must take shape before the gaseous disk dissipates under the intense radiation of the newly formed star. "To form a Jupiter, it's a race against the clock," Howard says. A metal-rich environment speeds the growth of the core, helping a gas giant take shape before it is too late. A smaller, rockier planet, on the other hand, is not as dependent on that ephemeral reservoir of gas; it can grow more gradually, even after the gas in the protoplanetary disk has evaporated.
"In my opinion, it points unambiguously to the fact that the formation of gas giant planets is quite a constrained process," says astronomer Debra Fischer of Yale University. An interesting question to pursue now, she says, is how low stellar metallicity can go before planet formation shuts off entirely.
The finding could bode well for Kepler's attempts and those of other exoplanet-finding campaigns, as small planets such as ours seem not to be picky about where they pop up. "Small planets could be widespread in our galaxy, simply because they don't need a special environment in which to form," Buchhave said.
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Add CommentWhile there may be many low metallicity terresstiral planets in the Milky Way, so far as we know complex lifeforms can only exist on planets with high metallicity.
Reply | Report Abuse | Link to thisBy astronomers' definition of "metal" (any element that's not hydrogen or helium), all terrestrial planets would be of high metallicity. what this article is saying is that small, high metallicity planets can form around low metallicity stars, but they do so slowly. Gas giants, on the other hand, can only form around high metallicity stars, because they need to form their metallic cores quickly so they can start gathering H & He before it all gets blown away.
Reply | Report Abuse | Link to thisThat's an interesting interpretation that seems to be supported only by this article.
Reply | Report Abuse | Link to thisTo quote the abstract of the referenced research report:
"Here we report spectroscopic metallicities of the host stars of 226 small exoplanet candidates discovered by NASA’s Kepler mission, including objects that are comparable in size to the terrestrial planets in the Solar System. We find that planets with radii less than four Earth radii form around host stars with a wide range of metallicities (but on average a metallicity close to that of the Sun), whereas large planets preferentially form around stars with higher metallicities. This observation suggests that terrestrial planets may be widespread in the disk of the Galaxy, with no special requirement of enhanced metallicity for their formation."
While I can't access the entire pay-per-view report, the summary does mention the dependence of gas giant formation on the availability of heavy elements, but it makes no mention of small terrestrial planets somehow accumulating heavy elements in a low metallicity protoplanetary disk.
Since heavy elements are produced by repeated generations of supernovae, as I understand a protoplanetary disk would either have a perponderence of heavy elements or it would not. While terrestrial planets may form in stellar systems with low metallicity, I don't find any mention of any mechanism by which they could somehow accumulate sufficient heavy elements to form a compositition comparable to Earth.
The complex life forms that we know, here on Earth, are 'heavily' dependent on the availability of many heavy elements, such as iron.
"...but it makes no mention of small terrestrial planets somehow accumulating heavy elements in a low metallicity protoplanetary disk"
Reply | Report Abuse | Link to thisSure it does - you even quoted it from the abstract: "We find that planets with radii less than four Earth radii form around host stars with a wide range of metallicities". It's clear to me that a "wide range" would include low-metallicity stars.
I think your misunderstanding is stemming from the fact that astronomers don't use the terms "metal" and "heavy element" in the same way that chemists do. The astronomers' definitions are much broader.
If I can chime in. The typical definition of 'metallicity' (i.e. the proportion of elements heaver than helium) is just the relative number of heavier atomic species than hydrogen, measured relative to the solar values. So 'low metallicity' simply means that there are fewer atoms of the heavier elements in a proto-stellar nebula, not that they're absent. There can of course be slightly different mixes of the heavier elements, but I don't think these particular results in the Nature paper are detailed enough to measure that.
Reply | Report Abuse | Link to thisSo while a system may be low in heavy elements relative to our solar system, it may still form smaller planets with a similar elemental mix to our terrestrial planets. Much of the final elemental composition of a small planet is a function of the rough and tumble of planet formation, at the whim of dynamical chaos. However, for giant planets, a deficit of heavier material makes it very hard for the enormous cores of these worlds to form *fast* enough to also accumulate the gaseous envelopes that eventually dominate their mass. The formation of lower mass planets is a more lengthy process and does not hinge on capturing vast amounts of the gas that is being evaporated from the system from almost the moment it coalesces from a nebula/molecular cloud.
And now for something completely different, please refer to the interpretations of a Science News reporter:
Reply | Report Abuse | Link to thishttp://news.sciencemag.org/sciencenow/2012/06/scienceshot-alien-earths-have.html?ref=hp
In my interpretation, the most telling statement is:
"Here we report spectroscopic metallicities of the host stars of 226 small exoplanet candidates..."
This indicates to me that only the spectroscopic matallicity of host stars was evaluated; that the candidate small exoplanets have not even been confirmed yet. Nothing has been determined about the metallicity of any possible small exoplanets. As I indicated, in the absence of contradictory evidence, I would expect that the metallicity of any small terrestrial exoplanets would proportionately reflect the metallicity of their protoplanetary disks, as indicated by the metallicity of their stellar progeny.
As I understand, the many recusions of nuclear fusion products dispersed by generations of supernovae increase both the atomic weight of individual elements and the abundance of proportionally heavier elements available within a protoplanetary disk.
Reply | Report Abuse | Link to thisA stated by http://en.wikipedia.org/wiki/Chemistry_of_life#Starting_materials:_the_chemical_elements_of_life
"Around two dozen of the 94 naturally-occurring chemical elements are essential to various kinds of biological life. Most rare elements on Earth are not needed by life (exceptions being selenium and iodine), while a few common ones (aluminum and titanium) are not used. Most organisms share element needs, but there are a few differences between plants and animals. For example ocean algae use bromine but land plants and animals seem to need none. All animals require sodium, but some plants do not. Plants need boron and silicon, but animals may not (or may need ultra-small amounts).
Just six elements—carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus—make up almost 99% of the mass of a human body (see composition of the human body for a complete list). In addition to the six major elements that compose most of the human body, humans require smaller amounts of possibly 18 more."
The elements required by the human body, as an example of complex life, is detailed in http://en.wikipedia.org/wiki/Composition_of_the_human_body#Elemental_composition
Of course, in addition to the critical trace elements necessary for human life, we also require an enormous supporting cast of simpler life forms with their own requirements.
I presume that a terrestrial planet that (assuming that it has an extra large iron core producing a significant protective magnetic field like the Earth's, etc.) must have adequate abundancies of necessary chemical elements to produce a diverse biosphere supporting the development of complex life forms.
Your comment is an odd one.
Reply | Report Abuse | Link to thisExactly what grounds do you base your comment that "so far as we know complex lifeforms can only exist on planets with high metallicity." considering that we have yet to discover any extraterrestrial life anywhere, and proving your statement true would require multiple discoveries around different systems to make the comparisons that would reveal those kinds of limits.
What you might be thinking of is the educated "speculation" of some scientists that expound on their own personal 'plausible sounding" hypothesis on the limitations life faces elsewhere in the universe, none of which have any proof to back them up.
If every field of science invents a private own terminology not connected to the terms in other sciences, this would produce a mesh much worse than the one in Babel's tower times. Using the name "Metals" to describe any element heavier than Hydrogen and Helium as the author of this interesting article does is somehow an insult for people having a degree in chemistry, and for most high-school students that do know that in the periodic table of the elements three main types of elements can be distinguished, initially called Metals, Non-metals and Metalloids, Noble elements (Those not reacting to form molecules with any type of the others, such as Helium and Neon).... I'm in doubt about whether the affirmation that "Astronomers use the name metals for anything heavier than Helium" is at all true. Salut +
Reply | Report Abuse | Link to thisThere's always the danger of assuming cause and effect.
Reply | Report Abuse | Link to thisFor instance, perhaps conditions that lend themselves to formation of jupiters also result in elevated metallicity, but as a result of and not the cause of elevated metallicity. And perhaps local SNe are only the primary means of raising metallicity. Perhaps metallicity can increase even stellar formation by in a stellar merger, by way of helium burning and alpha- and r-process nucleosynthesis.
Secondly, perhaps formation of jupiters require particularly-stable resonant planetary nurseries which only exit around wide-binary companion stars which accelerate planet formation before H2 dissipates from the protoplanetary disk. And perhaps wide-binary companion stars require an additional close-binary stellar pair as a source of energy and angular momentum to fuel the wide separation of the wide-binary pair. In other words, perturbation of a central binary pair by the other star may cause the close-binary orbits to decay and transfer their energy and angular momentum to increase the separation of the wide-binary pair.
And decay of a close-binary pair (of either star) may ultimately result in their merger in a luminous red nova (LRN), which raises the metallicity of the photospheres of both stars.
So jupiters may require a wide-binary companion star with a resonant planetary nursery, and wide-binary companions may require a close-binary stellar pair to feed off of, and a close binary pair may merge to create elevated metallicity. So jupiters may be indirectly rather than directly related to elevated metallicity.
Our own sun has a somewhat-elevated metallicity and a Jupiter which may have formed in a resonance nursery of a progenitor companion star. That companion start may still be in orbit, as Proxima Centauri. Both the sun and Proxima may have both formed as close-binary pairs in a quadruple star system, with the central binary pair merging in an LRN at 4.567 Ga. And the perturbation of Proxima's close-binary pair may have raised its solar orbit to 270,000 AU, where it is temporarily being deflected into a hyperbolic orbit around the passing star, Alpha Centauri.
Proxima may have formed the outer giant planets: Jupiter, Saturn, Uranus, Neptune, the Kuiper belt and the Oort cloud comets in succession its resonant planetesimal nurseries. Similarly, Jupiter may have formed Venus, Earth, Mars and the asteroid belt in succession around its own 2:1 to 3:1 resonant planetary nurseries.
"In the specialized usage of astronomy and astrophysics, the term "metal" is often used to refer collectively to all elements other than hydrogen or helium,"
Reply | Report Abuse | Link to thishttp://en.wikipedia.org/wiki/Metal
Salut+ back at you.
G'day
"Nothing has been determined about the metallicity of any possible small exoplanets."
Reply | Report Abuse | Link to thisBy definition, a small planet would need to be predominantly composed of heavier-than-helium (>He) elements, since they would lack sufficent mass to keep the solar wind from blowing away anything more than trace amounts of H or He.
As I indicated, in the absence of contradictory evidence, I would expect that the metallicity of any small terrestrial exoplanets would proportionately reflect the metallicity of their protoplanetary disks, as indicated by the metallicity of their stellar progeny."
Actually, small planets would contain a DISproportionately high concentration of >He elements, since the vast majority of the H & He that wasn't captured by the gravity of gas giants or the star itself would be rapidly blown out of the developing solar system. So, while the earliest stages of the disk would be mostly H & He, the later stages would be almost exlcusively >He, which would gradually accrete into small, rocky worlds.
"I presume that a terrestrial planet... must have adequate abundancies of necessary chemical elements to produce a diverse biosphere supporting the development of complex life forms."
Only if you're using a VERY tight definition of "terrestrial". Planet-hunting astronomers typically use a pretty loose definition - a planet with diameter and mass similar to the earth's. They don't (yet) factor in whether or not it has environmental conditions favorable to life, since the technology to measure such things is still very much in its infancy.
If I understand you, does the absence of evidence that complex life forms cannot exist on low metallicity planets justify speculation that they can?
Reply | Report Abuse | Link to this"By definition, a small planet would need to be predominantly composed of heavier-than-helium (>He) elements, since they would lack sufficient mass to keep the solar wind from blowing away anything more than trace amounts of H or He."
Reply | Report Abuse | Link to thisIs it not possible that a small/terrestrial planet could form without abundances of heavy elements that are most likely necessary for the development of complex life forms?
I think this study indicates that low metallicity star systems (much lower than the Sun) can produce small/terrestrial planets. There is no evidence available that these planets can accumulate heavier than iron trace elements (that are likely necessary to support complex life) from a protoplanetary disk that did not contain them in quantities proportional to our own.
BTW, I know that astronomers consider carbon to be a metal. Please see http://en.wikipedia.org/wiki/Supernova_nucleosynthesis
Reply | Report Abuse | Link to this"Supernova nucleosynthesis is the production of new chemical elements inside supernovae. It occurs primarily due to explosive nucleosynthesis during explosive oxygen burning and silicon burning. Those fusion reactions create the elements silicon, sulfur, chlorine, argon, sodium, potassium, calcium, scandium, titanium and iron peak elements: vanadium, chromium, manganese, iron, cobalt, and nickel. As a result of their ejection from individual supernovae, their abundances grow increasingly larger within the interstellar medium."
"There is no evidence available that these planets can accumulate heavier than iron trace elements (that are likely necessary to support complex life) from a protoplanetary disk that did not contain them in quantities proportional to our own."
Reply | Report Abuse | Link to thisIn fact, that is exactly what the article illustrates. Heavy Jupiter-like planets can NOT form in low-metallicity systems - possibly because the light gases are blown away before they can accumulate.
Hydrogen and Helium being the lightest of them all, will be blown away first. (There's so much of the two, that some will probably be left in some form.)
Heavier elements - and in particular elements heavier than iron - are less likely - indeed least likely - to be blown away.
This leaves us with the amusing conclusion, that low metallicity stars will be surrounded by planetary systems with a higher than average metallicity and vice versa.
In agreement with the observations described in the article.
(Yes, they have not analyzed the composition of the planets, but small planets are unlikely to be composed mainly of light elements - they would evaporate too quickly.)
To Madscientist 1972 and jtdwyer
Reply | Report Abuse | Link to thisThe pertinent question is the source from where the metallicity in a small terrestrial planet like our earth my appear. I could be either or combination of any one of following
i) From protoplanetary disc
ii) From a supernova
iii) From some asteroids independent of i)
iv) From the planet itself to be formed during
initial years of the life of planet
v) From a star other than the host stars of the
planet
A study of metallicity of planets in our solar system may provide some cue. Our solar system contains all sort of planets ranging from hot jupiter to rock earth and there appears to be no relation between distance from Sun to mass/size/composition
A very interesting perspective is offered in
Reply | Report Abuse | Link to thishttp://news.sciencemag.org/sciencenow/2012/06/you-owe-your-life-to-rock.html
"For much of its history, life on Earth existed as only single-celled organisms. Certain proteins critical for multicellular life, and presumed to have been equally critical for its evolution from single-celled ancestors, require heavy-metal elements, especially copper, zinc, and molybdenum, says John Parnell, a geoscientist at the University of Aberdeen in the United Kingdom. Previous studies suggest that multicellular life evolved sometime between 1.6 billion and 1.2 billion years ago. Researchers thought that before that innovation, these vital metals were locked away from environments where life thrived—either sequestered in the oxygen-poor depths of the ocean or held in ancient ore deposits in Earth's crust, waiting to be eroded."
It suggests not only that heavy elements be available within a planet, but volcanic activity and erosion of critical elements was necessary for the development of multicellular life after more than 2 billion years of the Earth's existence.
To Jtdwyer and Madscientist72
Reply | Report Abuse | Link to thisRef : Comments of Jtdwyer at 7
6 primary elements and 18 secondary elements necessary for the body of human beings - as per Wikilink. Are all these elements present in Sun from whose protoplanetary disc earth is presumed to be formed? If yes, we can safely presume that metallicity in a planet may emerge from protoplanetary disc of a star. Otherwise metallicity in a planet may be sourced from evolution of planet itself or from some asteroid or from some intra galactic body
To snowballsolarsystem (10)
Reply | Report Abuse | Link to thisYours is a very analytical interpretation of the formation of our planetary system but also appear to be quite complex and loaded with speculation. You are linking the origin of outer 4 planets and Oort cloud to Proxima Centuri and seeking birth of inner 4 planets and asteroid belt from Jupiter. In this process, you are keeping Sun totally out of picture. If your interpretation would have been right,
1) Why distance between Sun and Proxima is so wide to the extent of about 4.2 billion light years away. If you state that both Sun and Proxima had been part of same binary system then distance between Sun and planets should have been much more
11) Why planets rotate around Sun and not proxima Centuri
At one point, you are stating that pair of close binary system may merge to form a luminous red nova while at another point you are also stating that both Sun and Proxima may have formed as a close binary pair as a part of a quadruple star system. Is this not an intrinsic contradiction?
To Vinodsehgal (20),
Reply | Report Abuse | Link to thisIt's impossible to squeeze the theory into the 2500 character limit, so bear with me if you will.
So our quadruple-star system may have formed with interplay between 4 closely-spaced stellar members that may have formed inside of 1 AU. Hierarchy emerged in the form of a wide binary pair in which each wide-binary component was itself composed of a close binary pair: 2 + 2 = 4. Perturbation of the close-binary pairs by the other wide-binary companion caused energy and angular momentum to transfer from the two close-binary pairs to the wide-binary pair, increasing their separation.
Since perturbation is proportional to the inverse cube of the distance to the perturbator, at Oort cloud distances, close encounters with passing stars such as Alpha Centarui may have been dominant in perturbing Proxima's close-binary pair.
The central close-binary pair merged at 4.567 Ga to form a solitary Sun and the close-binary pair of the companion has apparently also merged more recently (when?) to form a solitary Proxima.
11) Why planets rotate around Sun and not Proxima Centauri? The Sun has 8 times the mass of Proxima, so the circular barycentric protoplanetary disk converted to an eccentric heliocentric orbit as Proxima's orbit inflation progressively overran the gas protoplanetary disk. The barycentric protoplanetary disk may have contained too much angular momentum to assume a tighter orbit around Proxima.?
Resonant planetesimal nurseries can form around either inner (2:1) heliocentric resonances with the companion Proxima or around outer (4:3) barycentric resonances with Proxima. But planetesimals/planets formed around outer resonances are subsequently overrun by Proxima in its continued orbit inflation, and formerly circular barycentric orbits are converted into highly-eccentric heliocentric orbits.
So inner and outer resonant nurseries form two dynamical classes of planetesimals/planets/comets: well behaved circular Class I planetesimals and highly-eccentric Class II planetesimals. Uranus (1.27 g/cm3) may be a low-density Class II planet formed further from the sun as colder temperatures than the Class I planet Neptune (1.638 g/cm3). Then Uranus was tossed backwards in its orbit toward the sun when it was overrun by Proxima during a close encounter with one member of the rapidly-rotating close-binary pair. And the subsequent circularizing an the highly-eccentric Class II orbit of Uranus accounts for its highly-inclined axial tilt.
"heavier than iron trace elements (that are likely necessary to support complex life)"
Reply | Report Abuse | Link to thisConsidering that me currently have exactly ONE planet's worth of biological data, statements about what is "likely necessary" to support ANY type of life is speculation, not science.
One little problem with your theory - the Proxima-aCenA-aCenB trinary system is currently moving closer to the sun (see http://en.wikipedia.org/wiki/Proxima_Centauri#Distance_and_motion). If the sun had once been part of the system as a double-binary and was flung out, they would be moving apart.
Reply | Report Abuse | Link to thisMadScientist72,
Reply | Report Abuse | Link to thisYes, both Alpha and Proxima currently have a positive radial velocity toward the sun, but I suggest the cause is Proxima's temporary (unbound) hyperbolic orbit around Alpha Centauri, a passing binary star twice the size of our sun and 18 times closer, so Proxima is currently experiencing 650 times the gravitational attraction to Alpha Centauri as to the Sun and is very much in its temporary grip.
To Snowballsolarsystem
Reply | Report Abuse | Link to thisAs you have stated, quadruple star star system was formed within 1 AU within which 4 stars were closely held. Within this distance, how do you define widely held binary pair and closely held binary pair in terms of distance and mass.
OK, then - to be more definitive, based strictly on the available evidence, complex life requires the availability of heavy elements. Presuming that complex life can form in the absence of necessary heavy elements is speculation not supported by any direct evidence.
Reply | Report Abuse | Link to thisAgain referring to http://news.sciencemag.org/sciencenow/2012/06/you-owe-your-life-to-rock.html
"Certain proteins critical for multicellular life, and presumed to have been equally critical for its evolution from single-celled ancestors, require heavy-metal elements, especially copper, zinc, and molybdenum, says John Parnell, a geoscientist at the University of Aberdeen in the United Kingdom."
"Presuming that complex life can form in the absence of necessary heavy elements is speculation not supported by any direct evidence."
Reply | Report Abuse | Link to thisPresuming that complex life CANNOT form in the absence of heavy elements is also speculation, based on a non-scientfic assumption that one planet's life represents the norm for the entire universe.
To vinodsehgal1957@yahoo.com
Reply | Report Abuse | Link to thisThe gas that condensed had too much angular momentum to form a single star and divided into 4 masses with 'interplay'. The close and wide binary pairing only arose, in the process of 'core collapse', as hierarchy emerged in the form of the 2+2 pairing, of the two largest stars and the two smallest.
In globular clusters, binary stars forestall core collapse until the binaries merge, and in our own pairing, once the binary Proxima merged (when?), Proxima and the Sun may continue the very-slow process of core collapse in which passing stars, such as Alpha Centauri, will perturb the pair, bringing them every closer together.
LOL! Since there is no evidence that any other life exists on any other planet, especially out side the Solar system, what evidence is there that this planet's life does _not_ represents the norm for the entire universe?
Reply | Report Abuse | Link to thisAre we to believe that anything is possible until proven not to exist, or only that which has been proven exists?
Are you a U.S. citizen or a British subject?
To Snowballsolarsystem
Reply | Report Abuse | Link to this1.0 Do you meant to state that one component of close binary merged with Proxima Centuri and another member merged with our Sun, Sun and Proxima dispersed away from each other (presently at about 4.2Gly) and ultimately Sun and Proxima Centuri shall also merge due to perturbation from Alpha Centuri? Planets in our solar system emerged from a protoplanetary disk rotating Proxima.
2.0 "The gas that condensed had too much angular momentum to form a single star and divided into 4 masses with 'interplay'."
Why single star split into only 4 masses - with one pair having small mass and another pair having large mass?
What made the conditions so "fine-tuned" to have exactly 4 stars - 2 with large masses and 2 with small masses.
If one believes in strong anthropic principle then it can be well understood but a coincidence does not appeals
You Owe Your Life To Natural Selection Of RNA. Period.
Reply | Report Abuse | Link to thisConsciousness-spirituality are brainchildren, and the brain is a progeny of mono-cells communities evolution:
From
Universe-Energy-Mass-Life Compilation
http://universe-life.com/2012/02/03/universe-energy-mass-life-compilation/
C. Know Thyself. Life Is Simpler Than We Are Told Including Origin-Nature Of Brain-Consciousness-“Spirituality”***
The origin-reason and the purpose-fate of life are mechanistic, ethically and practically valueless. Life is the cheapest commodity on Earth.
As Life is just another mass format, due to the oneness of the universe it is commonsensical that natural selection is ubiquitous for ALL mass formats and that life, self-replication, is its extension. And it is commonsensical, too, that evolutions, broken symmetry scenarios, are ubiquitous in all processes in all disciplines and that these evolutions are the “quantum mechanics” of the processes.
Human life is just one of many nature’s routes for the natural survival of RNAs, the base primal Earth organisms.
Life’s evolution, self-replication:
Genes (organisms) to genomes (organisms) to mono-cellular to multicellular organisms:
Individual mono-cells to cooperative mono-cells communities, “cultures”.
Mono-cells cultures evolve their communication, neural systems, then further evolving nerved multicellular organisms.
Human life is just one of many nature’s routes for the natural survival of RNAs, the base Earth organism.
It is up to humans themselves to elect the purpose and format of their life as individuals and as group-members.
Dov Henis (comments from 22nd century)
http://universe-life.com/
***המקור והמהות של "רוחניויות", כולן וירטואליות.
הרוחניויות נובעות מהמאמינים, לסיפוק ולשימוש שלהם.
.