Astroecology: Difference between revisions
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==Astroecology== |
==Astroecology== |
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| ⚫ | Astroecology concerns the interactions of biota with space environments. It studies resources for life on planets, asteroids and comets, and around various stars, in galaxies, and in the overall universe. The results of these studies allow estimating the future prospects for life, from planetary to galactic and cosmological scales <ref name = 'one' > {{Citation | last = Mautner | first = M. N.| title = Planetary Bioresources and Astroecology. 1. Planetary Microcosm Bioassays of Martian and Meteorite Materials: Soluble Electrolytes, Nutrients, and Algal and Plant Responses| journal = Icarus | volume = 158 | pages = 72-86 | year = 2002}} </ref> <ref name = 'two' > {{Citation | last = Mautner| first = M.N.| title = Life in the Cosmological Future: Resources, Biomass and Populations | journal = British Interplanetary Soc | volume = 58 | pages = 167-180 | year = 2005}} </ref> <ref name = 'twoa' > {{Cite book | last = Mautner | first = M.N. | author-link = M. N. Mautner| title = Seeding the Universe with Life: Securing Our Cosmological Future | publisher = Legacy Books, Washington D. C | date = 2000 }}</ref> |
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Experimental astroecology studies the biological resources in actual space materials from meteorites; the term “astroecology” was first applied in this context. <ref name = 'one' /> Early results have shown that meteorite/asteroid materials can support the growth of microorganisms, algae and plant cultures. Analysis of the essential nutrients (C, N, P, K) in meteorites yielded information for calculating the amount of biomass which can then be constructed asteroid resources. <ref name = 'one' /> |
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| ⚫ | Astroecology concerns the interactions of biota with space environments. It studies resources for life on planets |
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For example, results suggest that carbonaceous asteroids can yield a biomass on the order of six hundred million trillion (6e20) kgs. Available energy, and microgravity, radiation, pressure and temperature also affect astroecology. Also relevant are the ways by which life can reach space environments, including natural <ref name = 'three' > {{Citation | last = Kelvin | first = Lord.| title = | journal = Nature | volume = 4 | pages = 262 | year = 1871}} </ref> <ref name = 'four' > {{Citation | last = Weber | first = P.| last2 = Greenberg| first2 = Jose | title = Can spores survive in interstellar space?| journal = Nature | volume = 316 | pages = 403-407 | year = 1985 }} </ref> and directed panspermia <ref name = 'five' > {{Citation | last = Crick | first = F.H.| last2 = Orgel ] first2 = L.E. | title = Directed Panspermia| journal = Icarus | volume = 19 | pages = 341-348 | year = 1973 }} </ref> <ref name = 'six' > {{Citation | last = Mautner | first = M. | last2 = Matloff | first2 = G.L.| title = A Technical and Ethical Evaluation of Seeding the Universe | journal = Bulletin Amer. Ast. Soc | volume = 32 | pages = 419-423 | year = 1979}} </ref> <ref name = 'seven' > {{Citation | last = Mautner | first = M.N.| title = Directed Panspermia. 2. Technological Advances Toward Seeding Other Solar Systems | journal = J. British Interplanetary Soc | volume = 50 | pages = 93-102 | year = 1997}} </ref> |
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For human-based biological expansion into space, life-centered astroethics with a panbiotic commitment to propagate life are also relevant. <ref name = 'six' /> <ref name = 'seven' /> <ref name = “ eight” > {{Citation | last = Mautner | first = M.N.| title = Life-Centered Ethics, and the Human Future in Space | journal = Bioethics | volume = 23| pages = in press | year = 2009}} </ref> |
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Theoretical astroecology can quantify the |
Theoretical astroecology can quantify the amount of potential life, or the total biomass that could be supported over the duration of a biosphere ( BIOTA, Biomass Integrated Over Times Available l measured in kilogram-years). The biological resources, and the potential biomass and time-integrated biomass have been estimated for solar systems and for habitable zones around various stars, for the galaxy and or the universe. <ref name = 'two' /> <ref name = 'twoa' /> |
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For example, the limiting elements N and P in the estimated |
For example, the limiting elements N and P in the estimated 1e22kg carbonaceous asteroids could support 6e20kg biomass for the expected 5e9 years of the main-sequence Sun, yielding a future time-integrated BIOTA of 3e30kg-years in the Solar System. <ref name = 'one' /> <ref name = 'two' /> <ref name = 'twoa'/> |
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On the largest scale, cosmoecology concerns life in the galaxy and in the universe over cosmological |
On the largest scale, cosmoecology concerns the scope of life in the galaxy and in the universe over cosmological time periods. On these timescales, life may be limited by the available energy. Based on biological requirements of 100 Watts /kg biomass (Watts per kilogram biomass to sustain biological activity), radiated energy about red giant stars and white and red dwarf stars could support BIOTA up to 1e46 kg-years in the galaxy and 1e57 kg-years in the universe. |
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As an upper limit, the ultimate amount of life would be achieved if all matter was incorporated into biomass and then slowly converted to energy to sustain the biomass. This would yield 1e48 kg-years of time-integrated biomass in the galaxy and 1e59 kg-years of time-integrated biomass in the universe. <ref name = 'two' /> <ref name = 'twoa' /> |
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In summary, the results of experimental and theoretical astroecology |
In summary, the results of experimental and theoretical astroecology suggest an immense potential for future life in the universe. This potential may be realized through human action guided by life-centered astroethics. |
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==Experimental Astroecology: Biological Cultures on Meteorites== |
==Experimental Astroecology: Biological Cultures on Meteorites== |
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Experimental astroecology uses meteorites to assess nutrients in asteroids and planets. Chemical analysis of carbonaceous chondrite meteorites |
Experimental astroecology uses meteorites to assess nutrients in asteroids and on planets. Chemical analysis of carbonaceous chondrite meteorites <ref name = 'nine' > {{Citation | last = Jarosewich | first = E.| title = Chemical Analysis of the Murchison Meteorite | journal = Meteoritics | volume = 1 | pages = 49 | year = 1973}} </ref> <ref name = 'ninea' > {{Citation | last = Fuchs | first = L.H.| last2 = Olsen\ first2 = E. | last3 = Jensen | first3 = K.J. | title = Mineralogy, Mineral Chemistry and Composition of the Murchison (CM2) Meteorite | journal = Smithsonian Contributions to the Earth Sciences | volume = 10 | pages = 1-84 | year = 1973 }} </ref> <ref name = 'ten' > {{Citation | last = Mautner | first = M.N. | title = Planetary Resources and Astroecology. Electrolyte Solutions and Microbial Growth. Implications for Space Populations and Panspermia | journal = Astrobiology | volume = 2 pages = 59-76| year = 2002 }} </ref> shows that they contain extractable bioavailable water, organic carbon, and essential phosphate, nitrate and potassium nutrients. The results allow assessing the soil fertilities of the parent asteroids and planets, and the amounts of biomass that they can sustain. <ref name = 'one' /> <ref name = 'ten' /> |
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shows that they contain extractable bioavailable water, organic carbon, and the phosphate, nitrate and potassium. The results allow assessing the soil fertilities of the parent asteroids and planets, and the amounts of biomass that they can sustain. (Mautner, 2002) <ref> {{Citation | last = Mautner | first = M. N.| title = Planetary Bioresources and Astroecology. 1. Planetary Microcosm Bioassays of Martian and Meteorite Materials: Soluble Electrolytes, Nutrients, and Algal and Plant Responses| journal = Icarus | volume = 158 | pages = 72-86 | year = 2002}} </ref> (Mautner, 2002) <ref> {{Citation | last = Mautner | first = M.N. | title = Planetary Resources and Astroecology. Electrolyte Solautions and Microbial Growth. Implications for Space Populations and Panspermia | journal = Astrobiology | volume = 2 |
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pages = 59-76| year = 2002 }} </ref> |
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Can these resources |
Can these resources actually support life? Experiments showed that extracts of the Murchison CM2 meteorite can support high populations of organisms including bacteria (Nocardia asteroides), algae, and plant cultures including potato and asparagus. The microorganisms used organics in the carbonaceous meteorites as carbon sources. Algae and plant cultures also grew well on Mars meteorites. |
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The biomass that can be constructed from these resources |
The biomass that can be constructed from these resources can be calculated by comparing the concentration of elements in the resource materials and in biomass (Equation 1). <ref name = 'one'/> <ref name = ‘two’ /> <ref name = 'twoa' /> A given mass of resource materials (m¬resource) (kg) can support m(biomass,x) (kg) of biomass containing element x (considering x as the limiting nutrient), where c(resource,x) is the concentration of element x in the resource material (g/kg) and c(biomass,x) is its concentration in the biomass (g/kg). |
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| ⚫ | Carbonaceous asteroids contain about 1e22 kg potential resource materials. <ref name ='eleven' > {{Cite book | last = Lewis | first = J.S | author-link = J. S. Lewis| title = Physics and Chemistry of the Solar System | publisher = Academic Press, New York | date = 1997}} </ref> <ref name = 'elevena' > {{Cite book | last = Lewis | first = J. S. | author-link = J. S. Lewis | title = Mining the Sky | publisher = Helix Books, Reading, Massachusetts | date = 1996 }} </ref> <ref name = 'twelve' > {{Citation | last = O’Leary | first = B. T.| title = Mining the Apollo and Amor Asteroids | journal = Science | volume = 197 | pages = 363 | year = 1977 }} </ref> <ref name = 'thirteen' > {{Citation | last = O’Neill | first = G.K. | title = The Colonization of Space | journal = Physics Today | volume = 27 | pages = 32-38| year = 1974 }} </ref> <ref name = 'thirteena' > {{Cite book | last = O’Neill | first = G. K. | author-link = G. K. O’Neill | title = The High Frontier | publisher = William Morrow | date = 1977}} </ref> <ref name = 'fourteen' > {{Cite book | last = Hartmann | first = K. W. | author-link = K. W. Hartmann | title = The Resource Base in Our Solar System”, in Interstellar Migration and Human Experience | publisher = ed Ben R. Finney and Eric M. Jones, University of California Press, Berkley | date = 1985}} </ref> |
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| ⚫ | Carbonaceous asteroids contain about 1e22 kg potential resource materials. |
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From Equation (1), their critical resources (C (carbon), N (nitrogen) and P (phosphorus) ) can yield about 6e20 kg biomass (Table 1). |
From Equation (1), their critical resources (C (carbon), N (nitrogen) and P (phosphorus) ) can yield about 6e20 kg biomass (Table 1). |
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Table 1. Concentrations of elements in the carbonaceous chondrite (CM2) Murchison meteorite and in biomass, and the amounts of biomass that can be constructed from the meteorite materials. |
Table 1. Concentrations of elements in the carbonaceous chondrite (CM2) Murchison meteorite and in biomass, and the amounts of biomass that can be constructed from the meteorite materials. |
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ELEMENTS IN BIOMASSc |
ELEMENTS IN BIOMASSc |
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116 17 1.8 3.9 5.3 0.85 8.6 |
116 17 1.8 3.9 5.3 0.85 8.6 |
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WET BIOMASS (kg) CONSTRUCTED FROM ELEMENT X IN 1 kg OF |
WET BIOMASS (kg) CONSTRUCTED FROM ELEMENT X IN 1 kg OF METEORITE |
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From Water-Soluble Elements 0.016 0.00048 4.1 0.0013 0.57 5.3 0.04 |
From Water-Soluble Elements 0.016 0.00048 4.1 0.0013 0.57 5.3 0.04 |
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From Total Element Contents 0.16 0.06 18 0.28 2.5 140 >0.03 |
From Total Element Contents 0.16 0.06 18 0.28 2.5 140 >0.03 |
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Footnotes to Table 1. |
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a. Elements extracted in pure water at 120 oC for 15 minutes. Calcium (Ca), magnesium (Mg) and potassium (K) are extracted as elements; sulfur (S) as sulfate SO42-, nitrogen (N) as nitrate NO3- and phosphorus (P) as phosphate PO42- (Mautner, 2002) <ref> {{Citation | last = Mautner | first = M. N.| title = Planetary Bioresources and Astroecology. 1. Planetary Microcosm Bioassays of Martian and Meteorite Materials: Soluble Electrolytes, Nutrients, and Algal and Plant Responses| journal = Icarus | volume = 158 | pages = 72-86 | year = 2002}} </ref> (Mautner, 2002) <ref> {{Citation | last = Mautner | first = M.N. | title = Planetary Resources and Astroecology. Electrolyte Solautions and Microbial Growth. Implications for Space Populations and Panspermia | journal = Astrobiology | volume = 2 | pages = 59-76| year = 2002 }} </ref> |
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a. Elements extracted in pure water at 120 oC for 15 minutes. Calcium (Ca), magnesium (Mg) and potassium (K) are extracted as elements; sulfur (S) as sulfate SO42-, nitrogen (N) as nitrate NO3- and phosphorus (P) as phosphate PO42- <ref name = 'one' /> <ref name = 'ten' /> |
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b. Total concentrations (Jarosewich, 1973)<ref> {{Citation | last = Jarosewich | first = E.| title = Chemical Analysis of the Murchison Meteorite | journal = Meteoritics | volume = 1 | pages = 49 | year = 1973}} </ref> (Fuchs et al, 1973)<ref> {{Citation | last = Fuchs | first = L.H.| last2 = Olsen\ first2 = E. | last3 = Jensen | first3 = K.J. | title = Mineralogy, Mineral Chemistry and Composition of the Murchison (CM2) Meteorite | journal = Smithsonian Contributions to the Earth Sciences | volume = 10 | pages = 1-84 | year = 1973 }} </ref> |
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c. Elements in wet biomass, based on elements in dry biomass (Bowen, 1966) <ref> {{Cite book | last = Bowen | first = H. J. M. | author-link = H. J. M Bowen | title = Trace Elements in Biochemistry | publisher = Academic Press, New York | date = 1966}} </ref> and a ratio of wet/dry biomass = 4.0 d. Full wet biomass (kg) constructed from element x in 1 kg of meteorite if x is the limiting element (based on Equation (1)). To calculate the total biomass (kg) that can be constructed from the extractable or total materials of asteroids or comets, multiply the numbers in the bottom rows by 1022 kg or 1026 kg, respectively. (Lewis, 1997) <ref> {{Cite book | last = Lewis | first = J.S | author-link = J. S. Lewis| title = Physics and Chemistry of the Solar System | publisher = Academic Press, New York | date = 1997}} </ref> (Lewis, 1996) <ref> {{Cite book | last = Lewis | first = J. S. | author-link = J. S. Lewis | title = Mining the Sky | publisher = Helix Books, Reading, Massachusetts | date = 1996 }} </ref> |
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b. Total concentrations <ref name = “nine” /> <ref name = “ninea” /> |
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c. Elements in wet biomass, based on elements in dry biomass <ref name= 'fifteen' > {{Cite book | last = Bowen | first = H. J. M. | author-link = H. J. M Bowen | title = Trace Elements in Biochemistry | publisher = Academic Press, New York | date = 1966}} </ref> and a ratio of wet/dry biomass = 4.0 |
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| ⚫ | Assuming that 100,000 kg biomass supports one human, the asteroids may then sustain about 6e15 (six million billion) people, equal to a million Earths (a million times more than the present world population). Similar materials in the comets could support biomass and populations about one hundred times |
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d. Full wet biomass (kg) constructed from element x in 1 kg of meteorite if x is the limiting element (based on Equation (1)). To calculate the total biomass (kg) that can be constructed from the extractable or total materials of asteroids or comets, multiply the numbers in the bottom rows by 1e22 kg or 1e26 kg, respectively. <ref name = 'eleven' /> <ref name = 'elevena' /> |
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| ⚫ | Astroecology also concerns unavoidable wastage, such as the leakage of biological matter into space. This will cause an exponential decay of space-based biomass |
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| ⚫ | Assuming that 100,000 kg biomass supports one human, the asteroids may then sustain about 6e15 (six million billion) people, equal to a million Earths (a million times more than the present world population). Similar materials in the comets could support biomass and populations about one hundred times larger. Solar energy can readily sustain these populations for the predicted further five billion year lifespan of the Sun. These considerations yield a maximum time-integrated BIOTA of 3e30 kg-year in the Solar System. After the Sun becomes a white dwarf star <ref name = 'sixteen' > {{Cite book | last = Adams | first = F. | last2 = Laughlin | first 2 = G. | author-link = F. Adams and G. Laughlin | title = The Five Ages of the Universe | publisher = Touchstone Books, New York | date = 1999.}} </ref>, and other white dwarf stars, can provide energy for life much longer, for trillions of eons <ref name = 'seventeen' > {{Citation | last = Ribicky | first = K. R.| last2 = Denis | first2 = C.| title = On the Final Destiny of the Earth and the Solar System | journal = Icarus | volume = 151 | pages = 130-137 | year = 2001}} </ref> (Table 2) |
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Mbiomass,t = Mbiomass,oexp(-kt) (2) |
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| ⚫ | Astroecology also concerns unavoidable wastage, such as the leakage of biological matter into space. This will cause an exponential decay of space-based biomass <ref name = 'two' /> <ref name = 'twoa' /> as given by Equation (2), where M(biomass,o) is the mass of the original biomass, k is its rate of decay (the fraction lost in a unit time) and M(biomass,t) is the remaining biomass after time t. |
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M(biomass,t) = M(biomass,o)exp(-kt) (2) |
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BIOTA = |
BIOTA = M(biomass,o) / k (3) |
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For example, if 0.01% of the biomass is lost per year, then the time-integrated BIOTA equals 10, |
For example, if 0.01% of the biomass is lost per year, then the time-integrated BIOTA equals 10,000M(biomass,o). For the 6e20 kg biomass constructed from asteroid resources, this yields 6e24 kg-years of BIOTA in the Solar System. Even with this small rate of loss, life in the Solar System would disappear in a few hundred thousand years, and the potential total time-integrated BIOTA of 3e30 kg-years under the main-sequence Sun would decrease by a factor of 5e5, although a still substantial population of 1.2e12 (1.2 trillion) biomass-supported humans could exist through the habitable lifespan of the Sun. <ref name = 'two' /> <ref name ='twoa' /> |
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| ⚫ | The integrated biomass can be maximized by minimizing its rate of dissipation. If this rate can be reduced sufficiently, all the constructed biomass can last for the duration of the habitat, and it pays then to construct the biomass as fast as possible. However, if the rate of dissipation is significant, the construction rate of the biomass and its steady-state amounts may be reduced, but the reduced steady-state biomass and population can then last throughout the lifetime of the habitat. |
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| ⚫ | Should we build immense amounts of life that decays fast, or smaller, but still large, populations that last longer? Life-centered ethics suggests that life in the Solar System, and in the universe |
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| ⚫ | Should we build immense amounts of life that decays fast, or smaller, but still large, populations that last longer? Life-centered ethics suggests that life in the Solar System, and in the universe, should last as long as possible. <ref name = 'eighteen' > {{Citation | last = Mautner | first = M. N.| title = Life-Centered Ethics, and the Human Future in Space | journal = Bioethics | volume = | pages = in press| year = 2009}} </ref> |
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==Galactic Ecology== |
==Galactic Ecology== |
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The possible amounts of life in the Solar System are determined by material resources. However, when life reaches galactic proportions, technology should be able to access all material resources, and the scope of life will be defined by the supply of energy. The maximum amount of biomass about any star is then determined |
The possible amounts of life in the Solar System are determined by material resources. However, when life reaches galactic proportions, technology should be able to access all of the material resources, and the potential scope of life will be defined by the supply of energy. The maximum amount of biomass about any star is then determined by the energy requirements of the biomass and by the luminosity of the star. <ref name = 'two' /> <ref name = 'twoa' /> For example, considering that 1 kg biomass needs to be powered by 100 Watts of energy, we can calculate the steady-state amounts of biomass that can be sustained by stars with various energy outputs. These amounts are multiplied by the life-time of the star to calculate the time-integrated BIOTA about the star over the life-time of the star. Such results were obtained for various types of stars in the future galaxy. <ref name = 'two' /> <ref name = 'twoa' /> Using cosmological projections, <ref name = “sixteen” /> the potential amounts of future life in the galaxy and in the universe can then be quantified. <ref name = 'two' /> |
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For our Solar System from its origins to the present, the current 1e15 kg biomass over the past four billion years gives a time-integrated biomass (BIOTA) of 4e24 kg-years. In comparison, carbon, nitrogen, phosphorus and water in the 1e22 kg asteroids allows 6e20 kg biomass that can be sustained with energy for the 5 billion future years of the Sun, giving a BIOTA of 3e30 kg-years in the Solar System and 3e39 kg-years about 1e11 stars in the galaxy. Materials in comets could give biomass and time-integrated BIOTA a hundred times larger. After the Sun turns into a red giant, life in the outer Solar System can contribute significant further biomass for a billion years. <ref name = 'two' /> |
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The Sun will then become a white dwarf star, radiating 1e15 Watts of energy. It can provide power to 1e13 kg biomass for the immense life-span of a hundred million trillion (1e20) years, contributing a time-integrated BIOTA of 1e33 years. The 1e12 white dwarfs that may exist in the galaxy during this time can then contribute a time-integrated BIOTA of 1e45 kg-years in the galaxy. Red dwarf stars with luminosities of 1e23 Watts and life-times of 1e13 years can contribute 1e34 kg-years each, and 1e12 red dwarfs can contribute 1e46 kg-years, while brown dwarfs can contribute 1e39 kg-years of time-integrated biomass (BIOTA) in the galaxy. In total, the energy output of stars during 1e20 years can sustain a time-integrated biomass of about 1e45 kg-years in the galaxy. This is one billion trillion (1e20) times more life than has existed on the Earth to date. In the universe, stars in 1e11 galaxies could then sustain 1e57 kg-years of life. These vast amounts of living matter can allow unimaginable diversity in biology and intelligence. ,<ref name = 'two' /> |
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It is of interest to estimate the maximum amount of life that is possible in this universe. This amount of life would be achieved if all the mass in ordinary baryonic matter was converted to living matter. However, life requires energy, and a fraction of this mass would then need to be converted to energy to sustain biology. (Mautner, 2002) <ref> {{Citation | last = Mautner| first = M.N.| title = Life in the Cosmological Future: Resources, Biomass and Populations | journal = British Interplanetary Soc | volume = 58 | pages = 167-180 | year = 2005}} </ref> (Mautner, 2005) <ref> {{Cite book | last = Mautner | first = M.N. | author-link = M. N. Mautner| title = Seeding the Universe with Life: Securing Our Cosmological Future | publisher = Legacy Books, Washington D. C | date = 2000 }}</ref> |
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It is of interest to estimate the maximum amount of potential life in this universe. This amount of life would be achieved if all the mass in ordinary baryonic matter was converted to living matter. |
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| ⚫ | However, life requires energy, and a fraction of this mass would then need to be converted to energy to sustain biology. <ref name = 'two' /> <ref name = 'twoa' /> Assume that the power requirement is P(biomass) (J/sec kg) and the energy yield is Eyield) (J/kg) (Joules per kg biomass converted to energy). If the biomass is converted to energy at the rate required to provide the needed power for the remaining biomass, then the rate of decrease of biomass is given by equation <ref name ='four' /> |
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-dM(biomass)/dt) (kg/s) E(yield, biomass) (J/kg) = |
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P(biomass) (J/s kg) M(biomass) (kg) |
-dM(biomass)/dt) (kg/s) E(yield, biomass) (J/kg) = P(biomass) (J/s kg) M(biomass) (kg) (4) |
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This is similar to equation (3) with a rate of loss k(waste) = P(biomass)/E(yield,biomass). The remaining biomass after time t is given according to Equation (5) as |
This is similar to equation (3) with a rate of loss k(waste) = P(biomass)/E(yield,biomass). The remaining biomass after time t is given according to Equation (5) as |
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M(biomass,t) = M(biomass,o) exp |
M(biomass,t) = M(biomass,o) exp -((Pbiomass/Eyield, biomass) t) (5) |
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| ⚫ | With an energy requirement of 100W/kg biomass and with the maximum energy yield of e = mc^2 a fraction of 3.5e-8 of the biomass per year would need to be converted to energy, yielding about 3e7 kg-years of time-integrated BIOTA per kg biomass. An estimated 1e41 kg baryonic matter in the galaxy and 1e52 kg in the universe, all converted to biomass, would then yield 3e48 kg-years of time-integrated biomass in the galaxy and 3e59 kg-years of time-integrated biomass in the universe. <ref name = 'two' /> <ref name = 'twoa' /> |
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| ⚫ | With an energy requirement of 100W/kg biomass and with the maximum energy yield of e = mc^2 a fraction of 3.5e-8 of the biomass per year would need to converted to energy, yielding about 3e7 kg-years of time-integrated BIOTA per kg biomass. An estimated 1e41 kg baryonic matter in the galaxy and 1e52 kg in the universe, all converted to biomass, would then yield 3e48 kg-years of time-integrated biomass in the galaxy and 3e59 kg-years of time-integrated biomass in the universe. |
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==The Ultimate Future: Can Life Last Indefinitely?== |
==The Ultimate Future: Can Life Last Indefinitely?== |
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We can expand life in the galaxy through space travel |
We can expand life in the galaxy through space travel <ref name = 'nineteen' > {{Cite book | last = Hart | first = M. H. | author-link = M. H. Hart | title = Interstellar Migration, the Biological Revolution, and the Future of the Galaxy”, in Interstellar Migration and Human Experience | publisher = ed Ben R. Finney and Eric M. Jones, University of California Press, Berkeley | date = 1985 }} </ref> <ref name = 'nineteena' > {{Cite book | last = Mauldin | first = J. H.| author-link = J. H. Mauldin | title = Prospects for Interstellar Travel | publisher = AAS Publications, Univelt, San Diego | year = 1992 }} </ref> or directed panspermia (www.panspermia-society.com) The amounts of possible life that can be established in the galaxy, as projected by astroecology, are immense, but still finite. These projections are based on information about 15 billion past years since the Big Bang, but the habitable future is much longer, spanning trillions of eons. Our descendants may need to observe the cosmos on that time-scale to predict the future. Some cosmological scenarios may allow organized life to last indefinitely at an ever slowing rate, <ref name = 'twenty' > {{Citation | last = Dyson | first = F. | title = Without End: Physics and Biology in an Open Universe | journal = Rev. Modern Phys | volume = 51 | pages = 447-468 | year = 1979 }} </ref> <ref name = “twentya” > {{Cite book | last = Dyson | first = F. | author-link = F. Dyson | title = Infinite in All Directions | publisher = Harper and Row, New York | date = 1988}} </ref> or maybe even the laws of physics can be restructured, creating ever expanding universes <ref name = 'two' /> <ref name = 'twoa' /> permanently hospitable to life. |
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}} </ref> or restructuring the laws of physics to our advantage, creating ever expanding universes (Mautner, 2002) <ref> {{Citation | last = Mautner| first = M.N.| title = Life in the Cosmological Future: Resources, Biomass and Populations | journal = British Interplanetary Soc | volume = 58 | pages = 167-180 | year = 2005}} </ref> (Mautner, 2005) <ref> {{Cite book | last = Mautner | first = M.N. | author-link = M. N. Mautner| title = Seeding the Universe with Life: Securing Our Cosmological Future | publisher = Legacy Books, Washington D. C | date = 2000 }}</ref> |
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that are hospitable to life. |
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==Astroecology and Astroethics== |
==Astroecology and Astroethics== |
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Quantitative astroecology suggests that life can have an immense future in the galaxy and in the universe. <ref name = 'two' /> <ref name = 'twoa' /> We may secure this futureif we assure that life survives and that it propagates and expands in space. Our descendants may then understand nature more deeply and try to extend life indefinitely. This future for life can giving human existence a cosmic purpose. <ref name = 'two' /> <ref name = 'twoa' /> <ref name = 'eighteen' /> http://www.astroethics.com |
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Astroecology shows that life in the universe can have an immense future. [2] (Mautner, 2002) <ref> {{Citation | last = Mautner| first = M.N.| title = Life in the Cosmological Future: Resources, Biomass and Populations | journal = British Interplanetary Soc | volume = 58 | pages = 167-180 | year = 2005}} </ref> (Mautner, 2005) <ref> {{Cite book | last = Mautner | first = M.N. | author-link = M. N. Mautner| title = Seeding the Universe with Life: Securing Our Cosmological Future | publisher = Legacy Books, Washington D. C | date = 2000 }} </ref> This future may be in our hands, if we assure that life survives long-term and that expands in space. Our descendants may understand nature more deeply and try to extend life indefinitely, giving human existence can find a cosmic purpose.(Mautner, 2002) <ref> {{Citation | last = Mautner| first = M.N.| title = Life in the Cosmological Future: Resources, Biomass and Populations | journal = British Interplanetary Soc | volume = 58 | pages = 167-180 | year = 2005}} </ref> (Mautner, 2005) <ref> {{Cite book | last = Mautner | first = M.N. | author-link = M. N. Mautner| title = Seeding the Universe with Life: Securing Our Cosmological Future | publisher = Legacy Books, Washington D. C | date = 2000 }}</ref>(Mautner, 2009) <ref> {{Citation | last = Mautner| first = M. N.| title = Life-Centered Ethics, and the Human Future in Space | journal = Bioethics | volume = | pages = in press| year = 2009}} </ref>(WWW.ASTROETHICS.COM) |
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==References== |
==References== |
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Revision as of 22:15, 21 January 2009
Astroecology
Astroecology concerns the interactions of biota with space environments. It studies resources for life on planets, asteroids and comets, and around various stars, in galaxies, and in the overall universe. The results of these studies allow estimating the future prospects for life, from planetary to galactic and cosmological scales [1] [2] [3]
Experimental astroecology studies the biological resources in actual space materials from meteorites; the term “astroecology” was first applied in this context. [1] Early results have shown that meteorite/asteroid materials can support the growth of microorganisms, algae and plant cultures. Analysis of the essential nutrients (C, N, P, K) in meteorites yielded information for calculating the amount of biomass which can then be constructed asteroid resources. [1]
For example, results suggest that carbonaceous asteroids can yield a biomass on the order of six hundred million trillion (6e20) kgs. Available energy, and microgravity, radiation, pressure and temperature also affect astroecology. Also relevant are the ways by which life can reach space environments, including natural [4] [5] and directed panspermia [6] [7] [8]
For human-based biological expansion into space, life-centered astroethics with a panbiotic commitment to propagate life are also relevant. [7] [8] [9]
Theoretical astroecology can quantify the amount of potential life, or the total biomass that could be supported over the duration of a biosphere ( BIOTA, Biomass Integrated Over Times Available l measured in kilogram-years). The biological resources, and the potential biomass and time-integrated biomass have been estimated for solar systems and for habitable zones around various stars, for the galaxy and or the universe. [2] [3]
For example, the limiting elements N and P in the estimated 1e22kg carbonaceous asteroids could support 6e20kg biomass for the expected 5e9 years of the main-sequence Sun, yielding a future time-integrated BIOTA of 3e30kg-years in the Solar System. [1] [2] [3]
On the largest scale, cosmoecology concerns the scope of life in the galaxy and in the universe over cosmological time periods. On these timescales, life may be limited by the available energy. Based on biological requirements of 100 Watts /kg biomass (Watts per kilogram biomass to sustain biological activity), radiated energy about red giant stars and white and red dwarf stars could support BIOTA up to 1e46 kg-years in the galaxy and 1e57 kg-years in the universe. As an upper limit, the ultimate amount of life would be achieved if all matter was incorporated into biomass and then slowly converted to energy to sustain the biomass. This would yield 1e48 kg-years of time-integrated biomass in the galaxy and 1e59 kg-years of time-integrated biomass in the universe. [2] [3] In summary, the results of experimental and theoretical astroecology suggest an immense potential for future life in the universe. This potential may be realized through human action guided by life-centered astroethics.
Experimental Astroecology: Biological Cultures on Meteorites
Experimental astroecology uses meteorites to assess nutrients in asteroids and on planets. Chemical analysis of carbonaceous chondrite meteorites [10] [11] [12] shows that they contain extractable bioavailable water, organic carbon, and essential phosphate, nitrate and potassium nutrients. The results allow assessing the soil fertilities of the parent asteroids and planets, and the amounts of biomass that they can sustain. [1] [12]
Can these resources actually support life? Experiments showed that extracts of the Murchison CM2 meteorite can support high populations of organisms including bacteria (Nocardia asteroides), algae, and plant cultures including potato and asparagus. The microorganisms used organics in the carbonaceous meteorites as carbon sources. Algae and plant cultures also grew well on Mars meteorites.
The biomass that can be constructed from these resources can be calculated by comparing the concentration of elements in the resource materials and in biomass (Equation 1). [1] [13] [3] A given mass of resource materials (m¬resource) (kg) can support m(biomass,x) (kg) of biomass containing element x (considering x as the limiting nutrient), where c(resource,x) is the concentration of element x in the resource material (g/kg) and c(biomass,x) is its concentration in the biomass (g/kg). m(biomass,x) = m(resource,x) (cresource,x / cbiomass,x) (1) Carbonaceous asteroids contain about 1e22 kg potential resource materials. [14] [15] [16] [17] [18] [19]
From Equation (1), their critical resources (C (carbon), N (nitrogen) and P (phosphorus) ) can yield about 6e20 kg biomass (Table 1). Table 1. Concentrations of elements in the carbonaceous chondrite (CM2) Murchison meteorite and in biomass, and the amounts of biomass that can be constructed from the meteorite materials.
ELEMENT x C N S P Ca Mg K Water ELEMENTS IN METEORITE Bioavailable water-soluble elemental contentsa 1.8 0.008 7.6 0.005 3.0 4.0 0.34 100b Total contentsb 18.6 1.0 32.4 1.1 13 114 >0.28 100 ELEMENTS IN BIOMASSc 116 17 1.8 3.9 5.3 0.85 8.6 WET BIOMASS (kg) CONSTRUCTED FROM ELEMENT X IN 1 kg OF METEORITE From Water-Soluble Elements 0.016 0.00048 4.1 0.0013 0.57 5.3 0.04 From Total Element Contents 0.16 0.06 18 0.28 2.5 140 >0.03
Footnotes to Table 1. a. Elements extracted in pure water at 120 oC for 15 minutes. Calcium (Ca), magnesium (Mg) and potassium (K) are extracted as elements; sulfur (S) as sulfate SO42-, nitrogen (N) as nitrate NO3- and phosphorus (P) as phosphate PO42- [1] [12]
b. Total concentrations [20] [21]
c. Elements in wet biomass, based on elements in dry biomass [22] and a ratio of wet/dry biomass = 4.0
d. Full wet biomass (kg) constructed from element x in 1 kg of meteorite if x is the limiting element (based on Equation (1)). To calculate the total biomass (kg) that can be constructed from the extractable or total materials of asteroids or comets, multiply the numbers in the bottom rows by 1e22 kg or 1e26 kg, respectively. [14] [15]
Assuming that 100,000 kg biomass supports one human, the asteroids may then sustain about 6e15 (six million billion) people, equal to a million Earths (a million times more than the present world population). Similar materials in the comets could support biomass and populations about one hundred times larger. Solar energy can readily sustain these populations for the predicted further five billion year lifespan of the Sun. These considerations yield a maximum time-integrated BIOTA of 3e30 kg-year in the Solar System. After the Sun becomes a white dwarf star [23], and other white dwarf stars, can provide energy for life much longer, for trillions of eons [24] (Table 2)
Effects of Wastage
Astroecology also concerns unavoidable wastage, such as the leakage of biological matter into space. This will cause an exponential decay of space-based biomass [2] [3] as given by Equation (2), where M(biomass,o) is the mass of the original biomass, k is its rate of decay (the fraction lost in a unit time) and M(biomass,t) is the remaining biomass after time t.
M(biomass,t) = M(biomass,o)exp(-kt) (2)
Integration from time zero to infinity yields Equation (3) for the total time-integrated biomass ( BIOTA) contributed by this biomass. BIOTA = M(biomass,o) / k (3)
For example, if 0.01% of the biomass is lost per year, then the time-integrated BIOTA equals 10,000M(biomass,o). For the 6e20 kg biomass constructed from asteroid resources, this yields 6e24 kg-years of BIOTA in the Solar System. Even with this small rate of loss, life in the Solar System would disappear in a few hundred thousand years, and the potential total time-integrated BIOTA of 3e30 kg-years under the main-sequence Sun would decrease by a factor of 5e5, although a still substantial population of 1.2e12 (1.2 trillion) biomass-supported humans could exist through the habitable lifespan of the Sun. [2] [3] The integrated biomass can be maximized by minimizing its rate of dissipation. If this rate can be reduced sufficiently, all the constructed biomass can last for the duration of the habitat, and it pays then to construct the biomass as fast as possible. However, if the rate of dissipation is significant, the construction rate of the biomass and its steady-state amounts may be reduced, but the reduced steady-state biomass and population can then last throughout the lifetime of the habitat.
Should we build immense amounts of life that decays fast, or smaller, but still large, populations that last longer? Life-centered ethics suggests that life in the Solar System, and in the universe, should last as long as possible. [25]
Galactic Ecology
The possible amounts of life in the Solar System are determined by material resources. However, when life reaches galactic proportions, technology should be able to access all of the material resources, and the potential scope of life will be defined by the supply of energy. The maximum amount of biomass about any star is then determined by the energy requirements of the biomass and by the luminosity of the star. [2] [3] For example, considering that 1 kg biomass needs to be powered by 100 Watts of energy, we can calculate the steady-state amounts of biomass that can be sustained by stars with various energy outputs. These amounts are multiplied by the life-time of the star to calculate the time-integrated BIOTA about the star over the life-time of the star. Such results were obtained for various types of stars in the future galaxy. [2] [3] Using cosmological projections, [26] the potential amounts of future life in the galaxy and in the universe can then be quantified. [2] For our Solar System from its origins to the present, the current 1e15 kg biomass over the past four billion years gives a time-integrated biomass (BIOTA) of 4e24 kg-years. In comparison, carbon, nitrogen, phosphorus and water in the 1e22 kg asteroids allows 6e20 kg biomass that can be sustained with energy for the 5 billion future years of the Sun, giving a BIOTA of 3e30 kg-years in the Solar System and 3e39 kg-years about 1e11 stars in the galaxy. Materials in comets could give biomass and time-integrated BIOTA a hundred times larger. After the Sun turns into a red giant, life in the outer Solar System can contribute significant further biomass for a billion years. [2] The Sun will then become a white dwarf star, radiating 1e15 Watts of energy. It can provide power to 1e13 kg biomass for the immense life-span of a hundred million trillion (1e20) years, contributing a time-integrated BIOTA of 1e33 years. The 1e12 white dwarfs that may exist in the galaxy during this time can then contribute a time-integrated BIOTA of 1e45 kg-years in the galaxy. Red dwarf stars with luminosities of 1e23 Watts and life-times of 1e13 years can contribute 1e34 kg-years each, and 1e12 red dwarfs can contribute 1e46 kg-years, while brown dwarfs can contribute 1e39 kg-years of time-integrated biomass (BIOTA) in the galaxy. In total, the energy output of stars during 1e20 years can sustain a time-integrated biomass of about 1e45 kg-years in the galaxy. This is one billion trillion (1e20) times more life than has existed on the Earth to date. In the universe, stars in 1e11 galaxies could then sustain 1e57 kg-years of life. These vast amounts of living matter can allow unimaginable diversity in biology and intelligence. ,[2]
Cosmo-Ecology, and the Maximum Amounts of Potential Life in the Universe
It is of interest to estimate the maximum amount of potential life in this universe. This amount of life would be achieved if all the mass in ordinary baryonic matter was converted to living matter. However, life requires energy, and a fraction of this mass would then need to be converted to energy to sustain biology. [2] [3] Assume that the power requirement is P(biomass) (J/sec kg) and the energy yield is Eyield) (J/kg) (Joules per kg biomass converted to energy). If the biomass is converted to energy at the rate required to provide the needed power for the remaining biomass, then the rate of decrease of biomass is given by equation [5]
-dM(biomass)/dt) (kg/s) E(yield, biomass) (J/kg) = P(biomass) (J/s kg) M(biomass) (kg) (4)
This is similar to equation (3) with a rate of loss k(waste) = P(biomass)/E(yield,biomass). The remaining biomass after time t is given according to Equation (5) as
M(biomass,t) = M(biomass,o) exp -((Pbiomass/Eyield, biomass) t) (5)
With an energy requirement of 100W/kg biomass and with the maximum energy yield of e = mc^2 a fraction of 3.5e-8 of the biomass per year would need to be converted to energy, yielding about 3e7 kg-years of time-integrated BIOTA per kg biomass. An estimated 1e41 kg baryonic matter in the galaxy and 1e52 kg in the universe, all converted to biomass, would then yield 3e48 kg-years of time-integrated biomass in the galaxy and 3e59 kg-years of time-integrated biomass in the universe. [2] [3]
If all the biomass consisted of 100 kg humans, this would allow 1e39 humans in the galaxy living 3e46 human-years and 1e57 human-years in the universe. These estimates illustrate the immense potential amounts of biological and human life in the universe.
The Ultimate Future: Can Life Last Indefinitely?
We can expand life in the galaxy through space travel [27] [28] or directed panspermia (www.panspermia-society.com) The amounts of possible life that can be established in the galaxy, as projected by astroecology, are immense, but still finite. These projections are based on information about 15 billion past years since the Big Bang, but the habitable future is much longer, spanning trillions of eons. Our descendants may need to observe the cosmos on that time-scale to predict the future. Some cosmological scenarios may allow organized life to last indefinitely at an ever slowing rate, [29] [30] or maybe even the laws of physics can be restructured, creating ever expanding universes [2] [3] permanently hospitable to life.
Astroecology and Astroethics
Quantitative astroecology suggests that life can have an immense future in the galaxy and in the universe. [2] [3] We may secure this futureif we assure that life survives and that it propagates and expands in space. Our descendants may then understand nature more deeply and try to extend life indefinitely. This future for life can giving human existence a cosmic purpose. [2] [3] [25] http://www.astroethics.com
References
- ^ a b c d e f g Mautner, M. N. (2002), "Planetary Bioresources and Astroecology. 1. Planetary Microcosm Bioassays of Martian and Meteorite Materials: Soluble Electrolytes, Nutrients, and Algal and Plant Responses", Icarus, 158: 72–86
- ^ a b c d e f g h i j k l m n o p Mautner, M.N. (2005), "Life in the Cosmological Future: Resources, Biomass and Populations", British Interplanetary Soc, 58: 167–180
- ^ a b c d e f g h i j k l m n Mautner, M.N. (2000). Seeding the Universe with Life: Securing Our Cosmological Future. Legacy Books, Washington D. C.
- ^ Kelvin, Lord. (1871), Nature, 4: 262
{{citation}}: Missing or empty|title=(help) - ^ a b Weber, P.; Greenberg, Jose (1985), "Can spores survive in interstellar space?", Nature, 316: 403–407
- ^ Crick, F.H.; Orgel ] first2 = L.E. (1973), "Directed Panspermia", Icarus, 19: 341–348
{{citation}}: Missing pipe in:|last2=(help)CS1 maint: numeric names: authors list (link) - ^ a b Mautner, M.; Matloff, G.L. (1979), "A Technical and Ethical Evaluation of Seeding the Universe", Bulletin Amer. Ast. Soc, 32: 419–423
- ^ a b Mautner, M.N. (1997), "Directed Panspermia. 2. Technological Advances Toward Seeding Other Solar Systems", J. British Interplanetary Soc, 50: 93–102
- ^ Mautner, M.N. (2009), "Life-Centered Ethics, and the Human Future in Space", Bioethics, 23: in press
- ^ Jarosewich, E. (1973), "Chemical Analysis of the Murchison Meteorite", Meteoritics, 1: 49
- ^ Fuchs, L.H.; Olsen\ first2 = E.; Jensen, K.J. (1973), "Mineralogy, Mineral Chemistry and Composition of the Murchison (CM2) Meteorite", Smithsonian Contributions to the Earth Sciences, 10: 1–84
{{citation}}: Missing pipe in:|last2=(help)CS1 maint: numeric names: authors list (link) - ^ a b c Mautner, M.N. (2002), "Planetary Resources and Astroecology. Electrolyte Solutions and Microbial Growth. Implications for Space Populations and Panspermia", Astrobiology, 2 pages = 59-76
{{citation}}: Missing pipe in:|volume=(help) - ^ Cite error: The named reference
‘two’was invoked but never defined (see the help page). - ^ a b Lewis, J.S (1997). Physics and Chemistry of the Solar System. Academic Press, New York.
- ^ a b Lewis, J. S. (1996). Mining the Sky. Helix Books, Reading, Massachusetts.
- ^ O’Leary, B. T. (1977), "Mining the Apollo and Amor Asteroids", Science, 197: 363
- ^ O’Neill, G.K. (1974), "The Colonization of Space", Physics Today, 27: 32–38
- ^ O’Neill, G. K. (1977). The High Frontier. William Morrow.
- ^ Hartmann, K. W. (1985). The Resource Base in Our Solar System”, in Interstellar Migration and Human Experience. ed Ben R. Finney and Eric M. Jones, University of California Press, Berkley.
- ^ Cite error: The named reference
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“ninea”was invoked but never defined (see the help page). - ^ Bowen, H. J. M. (1966). Trace Elements in Biochemistry. Academic Press, New York.
- ^ Adams, F.; Laughlin (1999.). The Five Ages of the Universe. Touchstone Books, New York.
{{cite book}}: Check date values in:|date=(help); Unknown parameter|first 2=ignored (|first2=suggested) (help) - ^ Ribicky, K. R.; Denis, C. (2001), "On the Final Destiny of the Earth and the Solar System", Icarus, 151: 130–137
- ^ a b Mautner, M. N. (2009), "Life-Centered Ethics, and the Human Future in Space", Bioethics: in press
- ^ Cite error: The named reference
“sixteen”was invoked but never defined (see the help page). - ^ Hart, M. H. (1985). Interstellar Migration, the Biological Revolution, and the Future of the Galaxy”, in Interstellar Migration and Human Experience. ed Ben R. Finney and Eric M. Jones, University of California Press, Berkeley.
- ^ Mauldin, J. H. (1992). Prospects for Interstellar Travel. AAS Publications, Univelt, San Diego.
- ^ Dyson, F. (1979), "Without End: Physics and Biology in an Open Universe", Rev. Modern Phys, 51: 447–468
- ^ Dyson, F. (1988). Infinite in All Directions. Harper and Row, New York.