User:Mlhooten

Hello Fellow Human Beings.

Would appreciate an on or off-the-record dialogue about any of the following subjects:

Space Sciences - Knowledge Classification - Historical Giants - Constitutional Law - Health - Atmospheric Oxygen - Population Limits - Learning German - MagLev - Solar Energy -

Best to all of you.

Michael Hooten mlhooten&gmail.com

Concord, NC, USA

Retrieved from "http://en.wikipedia.org/wiki/User_talk:Mlhooten" +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Solar Hydrogen

Solar Hydrogen is a branch of the science of Solar Energy where sunlight is used either directly or indirectly to create hydrogen gas for use as energy. This science can be divided into several sub-sciences depending on which route is taken to derive hydrogen gas from sunlight: 1) Hydrogen gas can come from the electrolysis of water where the electrical source is solar electricity, derived from from hydroelectric, wind, photovoltaic or solarthermal, or biomass conversion. 2) Hydrogen gas can come from the very high temperature decoupling of water into hydrogen and oxygen if that very high temperature is generated by mirrors in a solar tower. 3) Hydrogen gas can come from Multijunction cell technology for photoelectrochemical (PEC) light harvesting that produces electricity from sunlight without the expense and complication of electrolyzers. 4)Certain photosynthetic microbes produce hydrogen from water in their metabolic activities. 5)Hydrogen can be produced via pyrolysis or gasification of biomass resources.

Advantages of Solar Hydrogen over Solar Electricity

Solar hydrogen has the advantage over solar electricity of being a gas, which makes it possibly transportable. Making hydrogen gas into a transportable liquid is not difficult for todays level of technical development and many methods have been invented, developed, tested and put on the market in a variety of applications. The disadvantage of solar hydrogen is that it usually must be derived from solar electriciy, creating a significant loss in overall efficiency. For this reason, a strong case can be made for electrifying any stationary application efficiently reachable by power lines, or simply converting existing fossil fuel power plants in sunny areas to solar electric plants. Electrified rails powered by solar electricity is an example of solar power applied to a transportation system. Hydrail (Hydrogen gas powered locomotives) are the Solar alternative to this as long as the hydrogen gas powering the locomotives is generated from sunlight.

Sunlight> Hydroelectric or PV or Solarthermal or Biomass > Electricity> Electrolysis > Hydrogen

The currently most available way to convert sunlight to hydrogen is to generate solar electricity from hydroelectric, wind, photovoltaic or solarthermal and then use that electricity as the source for the electrolysis of water. Many industrial electrolysis cells are very similar to Hofmann voltameters, with complex platinum plates or honeycombs as electrodes. Hydrogen gas is usually created, collected, and burned on the premises, as its energy density per volume is too low to make transporting or storing it economically feasible. Oxygen gas is treated as a byproduct.

Three generations of development The most common configuration of this device, the first generation photovoltaic, consists of a large-area, single layer p-n junction diode, which is capable of generating usable electrical energy from light sources with the wavelengths of solar light. These cells are typically made using silicon. However, successive generations of photovoltaic cells are currently being developed that may improve the photoconversion efficiency for future photovoltaics. The second generation of photovoltaic materials is based on multiple layers of p-n junction diodes. Each layer is designed to absorb a successively longer wavelength of light (lower energy), thus absorbing more of the solar spectrum and increasing the amount of electrical energy produced. The third generation of photovoltaics is very different from the other two, and is broadly defined as a semiconductor device which does not rely on a traditional p-n junction to separate photogenerated charge carriers. These new devices include dye sensitized cells, organic polymer cells, and quantum dot solar cells.

File:Hoffman voltameter.jpg

Hoffman electrolysis apparatus used in electrolysis of water

Main article: Electrolysis of water

One important use of electrolysis is to produce hydrogen gas. The reaction that occurs is

2H_{2O(aq) → 2H2(g) + O2(g)}

This has been suggested as a way of shifting society towards using hydrogen as an energy carrier for powering electric motors and internal combustion engines. (See hydrogen economy.)

The energy efficiency of water electrolysis varies widely. The efficiency is a measure of what fraction of electrical energy used is actually contained within the hydrogen. Some of the electrical energy is converted to heat, a useless by-product. Some reports quote efficiencies between 50–70%[1] This efficiency is based on the Lower Heating Value of Hydrogen. The Lower Heating Value of Hydrogen is thermal energy released when Hydrogen is combusted. This does not represent the total amount of energy within the Hydrogen, hence the efficiency is lower than a more strict definition. Other reports quote the theoretical maximum efficiency of electrolysis. The theoretical maximum efficiency is between 80–94%.[2]. The theoretical maximum considers the total amount of energy absorbed by both the hydrogen and oxygen. These values only refer to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included. For instance, when considering a power plant that converts the heat of nuclear reactions into hydrogen via electrolysis, the total efficiency is more like 25–40%.[3]

Electrolysis of water is an electrolytic process which decomposes water into oxygen and hydrogen gas with the aid of an electric current, where a power source from a 6 volt battery is commonly used. The electrolysis cell consists of two electrodes (usually an inert metal such as platinum) submerged in an electrolyte and connected to opposite poles of a source of direct current. Many industrial electrolysis cells are very similar to Hofmann voltameters, with complex platinum plates or honeycombs as electrodes. Hydrogen gas is usually created, collected, and burned on the premises, as its energy density per volume is too low to make transporting or storing it economically feasible. Oxygen gas is treated as a byproduct.

Main article: High-temperature electrolysis

High-temperature electrolysis (also HTE or steam electrolysis) is a method currently being investigated for water electrolysis with a heat engine. High temperature electrolysis is more efficient than traditional room-temperature electrolysis because some of the energy is supplied as heat, which is cheaper than electricity, and because the electrolysis reaction is more efficient at higher temperatures. This method should not be confused with very high temperature water splitting.

Applications

About four percent of hydrogen gas produced worldwide is created by electrolysis, and normally used onsite. Hydrogen is used for the creation of ammonia for fertilizer via the Haber process, and converting heavy petroleum sources to lighter fractions via hydrocracking. There is some speculation about future development of hydrogen as an energy carrier.

Efficiency

The energy efficiency of water electrolysis varies widely. Some report 50–70%[4], while others report 80–94%.[5] These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included. For instance, when considering a power plant that converts the heat of nuclear reactions into hydrogen via electrolysis, the total efficiency is more like 25–40%.[6]

NREL is testing integrated electrolysis systems and investigating options for improved designs that will lower capital costs and improve performance for intermittent electrolysis. This project is carried out in collaboration with other DOE offices including the Wind & Hydropower, Distributed Energy & Electric Reliability, and Biomass Programs.

Sunlight> SolarThermal Power> High Temperature Decoupling > Hydrogen

Using outside mirrors placed in arrays, refelecting the suns rays to central receiving tower (Solar Tower); that concentrated solar energy can be used to generate temperatures of over 2,000 degrees at which thermochemical reaction cycles can be used to produce hydrogen without the intervention of electrolysis.

references: Jaimee Dahl et al., High Temperature Solar Splitting of Methane to Hydrogen and Carbon, (2003) (PDF 696 KB) Jaimee Dahl et al., Rapid Solar-thermal Dissociation of Natural Gas in an Aerosol Flow Reactor, (2002) (PDF 428 KB)

Sunlight> Photo electrochemical> Hydrogen

Multijunction cell technology developed by the Photovoltaic industry is being used for photoelectrochemical (PEC) light harvesting systems that generate sufficient voltage to split water and are stable in a water/electrolyte environment. PEC system produces electricity from sunlight without the expense and complication of electrolyzers,

references: John Turner, Photoelectrochemical Water Splitting, (2003) (PDF 1.19 MB) K. Varner et al., Photoelectrochemical Systems for Hydrogen Production, (2002) (PDF 724 KB)

Sunlight> Biological Organisms> Hydrogen

Certain photosynthetic microbes use water to produce hydrogen gas in their metabolism. Photobiological technology has good possibilities, but because oxygen is produced along with the hydrogen, the technology must overcome the limitation of oxygen sensitivity of the enzyme systems.

references: Maria Ghirardi and Michael Seibert, Algal Hydrogen Photoproduction, (2003) (PDF 645 KB) Michael Seibert et al., Molecular Engineering of Algal Hydrogen Production, (2002) (PDF 741 KB) Maria Ghirardi et al., Cyclic Photobiological Algal Hydrogen Production, (2002) (PDF 303 KB)

Sunlight> Biomass > Pyrolysis> Hydrogen

Hydrogen can be produced via pyrolysis or gasification of biomass resources.

references: Kimberly Magrini-Bair et al., Fluidizable Catalysts for Hydrogen Production from Biomass Pyrolysis/Steam Reforming, (2003) (PDF 1 MB) Kimberly Magrini-Bair et al. , Fluidizable Catalysts for Producing Hydrogen by Steam Reforming Biomass Pyrolysis Liquids, (2002) (PDF 751 KB} Stefan Czernik , Hydrogen from Post-Consumer Residues, (2003) (PDF 922 KB) Stefan Czernik et al., Hydrogen Production from Post-Consumer Wastes, (2002) (PDF 387 KB) Robert J. Evans, Hydrogen from Biomass-Catalytic Reforming of Pyrolysis Vapors, (2003) (PDF 1.93 MB) Robert J. Evans et al., Engineering Scale Up of Renewable H2 Production by Catalytic Steam Reforming of Peanut Shells Pyrolysis Products, (2002) (PDF 531 KB)

See also

• Electrochemistry
• Electrolysis
• Hydrogen production
• Gas cracker

References

• "Electrolysis of Water". Experiments on Electrochemistry. Retrieved November 20. {{cite web}}: Check date values in: |accessdate= (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)
• "Electrolysis of Water". Do Chem 044. Retrieved November 20. {{cite web}}: Check date values in: |accessdate= (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)

Category:Electrochemistry Category:Physical chemistry Category:Electrolysis Category:Hydrogen production

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

  * Astronomical Methods
  * Descriptive Astronomy   
      Other Universes
      Universe
      Galactic Clusters
      Galaxies
      Solar Systems  
  * Astrophysics/Cosmology
  * Galactic Science
  * Solar Science
  * Planetary science 
      Planetary Geology
      Planetary Atmospheres
  * Exobiology 
  * Space exploration
      Astronautics/Space Transport 
      Space Station
  * Space colonization
  * Aeronautics  
  * Space Defense

+++++++++++++++

Space science topics

Space Science is an all-encompasing term that describes most all of the various sciences that are concerned with the study of the Universe, generally also meaning "excluding the Earth". Space Science can be divided into 9 overall categories: Looking At The Universe , Geography of the Universe, Physics of the Universe, , Geology of Other Planets, Oceans of Other Planets, Atmosphere of Other Planets, Life of Other Planets, , Travelling to Other Planets and Colonizing Other Planets.

Some of these sub sciences have well defined and well accepted terms and some do not. For instance Physics of The Universe is universally accepted as "Astrophysics" and Looking at the Universe is universally accepted as "Astronomy".

• Astronomy

       Solar System 
   * Astrophysics/Cosmology
   * Exobiology 
   * Space exploration
       Astronautics
       Space Transport (This has much in common with both the above)
       Space Station
   * Space colonization (there is huge overlap with Space Exploration)

Astronomical Methods Astronomy

Astronomy can also be called observational astrophysics.

Electromagnetic spectrum electromagnetic spectrum Astronomy

Radio astronomyRadio astronomy includes radio telescopes; a device that recieves and records radio waves from outside the Earth, cosmic microwave background radiation, Big Bang telescopes, Pulsars Telescopes and others

Infrared Astronomy Infrared Astronomy telescopes

Optical astronomy Optical astronomy is the oldest kind of astronomy and includes optical telescopes, Telescopes, charge-coupled device, spectroscope, adaptive optics, redshifted light Telescopes and others.

Ultraviolet Astronomy Ultraviolet Astronomy

X-ray astronomy X-ray Astronomy includes Chandra X-ray Observatory .

gamma ray astronomy gamma ray Astronomy includes Compton Gamma Ray Observatory, Cosmic ray, High Energy Bodies, binary pulsars, black holes, magnetars,

Neutrino astronomy Neutrino astronomy Neutrino observatories have also been built, primarily to study our Sun.

gravitational wave gravitational wave observatories

space telescope space telescope, a telescope orbiting or travelling from the Earth, RXTE, Long Exposure Time Astronomy, millisecond pulsar, pulsar decelerationstudies, Spectroscopy,

Astronomy teaching tools, Planetarium,

Descriptive Astronomy

Historical Geography of The Universe includes (Size Shape and Structure of The Historical Universe), Cartography of The Historical Universe, Early Universe and others.

The Current Universe includes Size Shape and Structure of The Current Universe, Cartography of the Current Universe and others

The Filaments of Galaxies

Superclusters of Galaxies includes superclusters,

The Virgo Supercluster of Galaxiesincludes Virgo Supercluster

The Local Group of Galaxies including objects 100,000,000 LY to 10,000,000 LY from the Sun: M49, M51, M58, M59, M60, M61, M63, M64, M65, M66

Nearby Galaxies: Objects 10,000,000 LY to 1,000,000 LY from the Sun: M31, M32, M33

Milky Way Galaxy Regions Galactic Center , Disc_Galaxy and Galactic Cartography, Galactic_Coordinate System

Celestial Objects 100,000 LY to 10,000 LY from the Sun: M2, M3, M5, M9, M10, M12, M13, M14, M15, M19, M22, M24, M28, M36, M53, M54, M55, M56, M62

Celestial Objects 10,000 LY to 1000 LY Lfrom the Sun: M1, M4, M6, M7, M8, M11, M16, M17, M18, M20, M21, M23, M25, M26, M27, M29, M41, M42, M43, M46, M47, M48, M50, M52, M57

Celestial Objects 1000 LY to 100 LY from the Sun: M39, M44, M45

Celestial Objects 100 LY to 16LY From the Sun

Celestial Objects less than 16 LY from the Sun: List of Nearest Stars

Nearby-Stars Solar Systems

The Solar System includes Solar system

The Sunincludes Sun

Luncar Science includes Moon, List of artificial objects on the Moon, List of craters on the Moon, List of features on the Moon, List of maria on the Moon, List of mountains on the Moon, List of valleys on the Moon

Scientific Study of Venus includes Venus

Scientific Study of Mercury And Its Moons includes Mercury

Scientific Study of Saturn And Its Moons includes Saturn

Jupiter And Its Moons includes Jupiter

Uranus includes Uranus

Neptune includes Neptune

Scientific Study of Mars and Its Moons includes Mars

Geodesy of The Solar System, also called geodetics of the solar system, is the scientific discipline that deals with the measurement and representation of the planets of the Solar System, their gravitational fields and geodynamic phenomena (polar motion, in three-dimensional, time-varying space.

The shape of the planets are to a large extent the result of their rotation, which causes equatorial bulge, and the competition of geologic processes such as the collision of plates and of vulcanism, resisted by the earth's gravity field. This applies to the solid surface (orogeny; few mountains are higher than 10 km, few deep sea trenches deeper than that.) Quite simply, a mountain as tall as, for example, 15 km, would develop so much pressure at its base, due to gravity, that the rock there would become plastic, and the mountain would slump back to a height of roughly 10 km in a geologically insignificant time. (On Mars, whose surface gravity is much less, the largest volcano, Olympus Mons, is 27 km high at its peak, a height that could not be maintained on Earth.) Gravity similarly affects the liquid surface (dynamic sea surface topography) and the earth's atmosphere. For this reason, the study of the Earth's gravity field is seen as a part of geodesy, called physical geodesy.

The Earth geoid is essentially the figure of the Earth abstracted from its topographic features. so The Marsgeoid is essentially the figure of Mars abstracted from its topographic features. In surveying and mapping are two important fields of application of geodesy.

Physics Of The Universe Astrophysics

Physics of the Universe can be divided into several broad categories:

Astrophyscial Theory including String Theory|String and [General Relativity] and others.

Astrophysical Processes includes baryonic and others.

Physical Processes, General includes Mechanics, Electromagnetism,electromagnetic forces, Statistical Mechanics, Thermodynamics, Quantum Mechanics, Relativity, gravity and oters.

Origins Of The Universe Universe Theories of the Origins of the Universe, Big Bang Theory, Early Universe, Evidence, Cosmic Microwave Background, Dark Ages, Interstellar Medium , voids, Filaments of Galaxies , galaxy clusters and others.

Astrophysical Plasma includes plasma amd quasineutrality and others

Cosmic Plasmas Between Stars, (Diffuse Plasmas) includes intergalactic space, intergalactic medium, interstellar medium, interplanetary medium, interstellar space, heliospheric current sheet, interplanetary medium, Solar wind and otehrs.

Cosmic Plasmas Inside Stars, (Dense Plasma) includes Stars, plasma physicists, active galactic nuclei, fusion power, magnetohydrodynamic, X-rays , bremsstrahlung, Cosmology , reionized, ambipolar diffusion, Particle Physics and others.

Galaxy Formation and Evolution including Galaxies, elliptical galaxies Giant Galaxies, Spiral Galaxies, M31 The Andromeda Galaxy

Intra-Galaxy Processes, General including Black Hole, Globular Clusters, Satellite Galaxy , Retrograde Rotation, Halo stars, High Velocity Clouds, Monoceros Ring, accretion disc, Gravitation, Angular Momentum, Centripetal force, tidal effects, Viscosity, orbital momentum, Accretion disk, Active galactic nuclei, Protoplanetary discs, Gamma ray bursts and others.

Milky Way Galaxy Processes Science include aspects of Milky Way Retrograde Rotation, Halo stars, Milky Way High Velocity Clouds, Milky Way Neutral Hydrogen, Milky Way Monoceros Ring, Milky Way accretion disc, Milky Way Gravitation, Milky Way Angular Momentum, Milky Way Centripetal force, Milky Way tidal effects, Milky Way Viscosity, Milky Way orbital momentum, Milky Way event horizon, Milky Way black hole and others.

Stellar-Processes, General including Stellar_dynamics, stars, Stellar Evolution, event horizon, black hole, x-rays, nuclear fusion and others.

Planetary Processes, General including Planetary science, Planets, Comets, Asteroids,

Geophysics, the study of the earth by quantitative physical methods, especially by seismic, electromagnetic, and radioactivity methods, therefore Planetary Geophysics the study of the planets by quantitative physical methods, especially by seismic, electromagnetic, and radioactivity methods. It includes the branches of: Seismology (earthquakes and elastic waves), gravity and geodesy (the earth's gravitational field and the size and form of the earth) [Tectonophysics]] (geological processes in the planets), Geodesy, Mineral Physics. Geophysics can be both a part of physics and a part of Geology.

Non-Earth Planetary science

Planetary geology (sometimes known as Astrogeology) refers to the application of geologic principles to other bodies of the solar system. However, specialised terms such as selenology (studies of the Moon), areology (of Mars), etc., are also in use.

Important principles of geology. There are a number of important principles in geology. Many of these involve the ability to provide the relative ages of strata or the manner in which they were formed. The Principle of Intrusive Relationships concerns crosscutting intrusions. In geology, when an igneous intrusion cuts across a formation of sedimentary rock, it can be determined that the igneous intrusion is younger than the sedimentary rock. The Principle of Cross-cutting Relationships pertains to the formation of faults and the age of the sequences through which they cut.

Geology Fields or related disciplines Structural geology, Geomorphology.]], Economic geology, Mining geology, Geodetics, Geomorphology, Geophysics, Historical geology, Hydrogeology or geohydrology, Mineralogy, Oceanography, Paleoclimatology, Sedimentology, Seismology, Stratigraphy, Structural geology, Volcanology,Hydrology water throughout the Earth, and thus addresses both the hydrologic cycle and water resources, Main article: Hydrologic cycle

Regional geology

Geology of Mercury

Geology of Venus

Geology of the Moon

Geology of Mars

Geology of Jupiter

Geology of Saturn

Geology of Uranus

[Neptune#Physical_characteristics|Geology of Neptune]]

Geology of Pluto (No longer a planet)

Atmosphere of Other Planets / Extrasolar Atmosphere Atmosphere of Planets Outside The Solar Systemincludes Theoretical Atmosphere of Planets Outside The Solar System

Atmosphere on Planets of The Solar Systemincludes Theoretical Atmosphere of Solar System Planets, and Atmosphere on Other Solar System Planets http://www.astronomy.org/astronomy-survival/outer.html

Mars Atmosphere includes Mars AtmosphereTheories of Atmosphere on Mars

Venus Atmosphere includes Theories of Atmosphere on Venus

Jupiter Atmosphere [7] includes Theories of Atmosphere on Jupiter Jupiter Atmosphere[Great Red Spot Great Red Spot] http://www2.jpl.nasa.gov/galileo/mess44/promysso.html, Atmosphere on Jupiters-Moons , Theories of Atmosphere on J. Moons

Atmosphere on Saturn includes Theories of Atmosphere on Saturn, http://www.nasm.si.edu/ceps/rpif/saturn/saturn.html http://www.physics.purdue.edu/astr263l/SStour/saturn.html http://www.abc.net.au/science/news/stories/s872839.htm

Atmosphere on Urnaus includes Theories of Atmosphere on Uranus, http://www.physics.purdue.edu/astr263l/SStour/uranus.html

Atmosphere of Planets Outside The Solar Systemincludes Theoretical Atmosphere of Planets Outside The Solar System

Atmosphere on Planets of The Solar Systemincludes Theoretical Atmosphere of Solar System Planets, and Atmosphere on Other Solar System Planets http://www.astronomy.org/astronomy-survival/outer.html

Mars Atmosphere includes Mars AtmosphereTheories of Atmosphere on Mars

Venus Atmosphere includes Theories of Atmosphere on Venus

Jupiter Atmosphere [8] includes Theories of Atmosphere on Jupiter Jupiter Atmosphere[Great Red Spot Great Red Spot] http://www2.jpl.nasa.gov/galileo/mess44/promysso.html, Atmosphere on Jupiters-Moons , Theories of Atmosphere on J. Moons

Atmosphere on Saturn includes Theories of Atmosphere on Saturn, http://www.nasm.si.edu/ceps/rpif/saturn/saturn.html http://www.physics.purdue.edu/astr263l/SStour/saturn.html http://www.abc.net.au/science/news/stories/s872839.htm

Atmosphere on Urnaus includes Theories of Atmosphere on Uranus, http://www.physics.purdue.edu/astr263l/SStour/uranus.html

• Atmospheric science, which includes: Atmospheric electricity and terrestrial magnetism (including ionosphere, Van Allen belts, telluric currents, Radiant energy, etc.), Meteorology and Climatology, which both involve studies of the weather. Aeronomy, the study of the physical structure and chemistry of the atmosphere.

Geothermometry (heating of the earth, heat flow, volcanology, and hot springs), Hydrology (ground and surface water, sometimes including glaciology), Physical oceanography

Biology of Other Planets / Extrasolar Biology / Exobiology / Extraterrestrial Life

Habitable Zone Astrobiology Which areas of the Universe would hold life..? Galactic Habitable Zone Which areas of a Galaxy would hold life? Solar System Habitable Zone Which areas of a solar system would hold life?

Astrobiochemistry http://en.wikipedia.org/wiki/Exogenesis Carbon based chemistry science

Most scientists hold that if extraterrestrial life exists, its evolution would have occurred independently in different places in the universe. An alternative hypothesis, held by a minority, is panspermia, which suggests that life in the universe could have stemmed from a smaller number of points of origin, and then spread across the universe, from habitable planet to habitable planet. These two hypotheses are not mutually exclusive.

Main article: Biochemistry

Alternative biochemistry includes Alternative Carbon Biochemistry where water is not the Solvent of Carbon Chains: Life forms based in ammonia rather than water are also considered, though this solution appears less optimal than water . Also included in Alternative Non-Carbon Biochemistry: For non-carbon based chemistry Silicon is usually considered the most likely alternative to carbon, though this remains improbable. Silicon life forms are proposed to have a crystalline morphology, and are theorized to be able to exist in high temperatures, such as planets closer to the sun.

Astrobiosphere is the entire area of a planet that supports life and includes Biosphere, Theory of Biosphere, http://en.wikipedia.org/wiki/Planetary_habitability Planetary Habitability Extrasolar planets Astronomers also search for extrasolar planets that would be conducive to life, especially those like OGLE-2005-BLG-390Lb which have been found to have Earth-like qualities.

Plants On Other Planets includes Extremophiles http://science.nasa.gov/headlines/y2003/02oct_goldilocks.htm?list554307, Theoretical Astrobotany, Life On Jupiter, [Life on Mars scientific theory], Independently in 1996 structures resembling bacteria were reportedly discovered in a meteorite, ALH84001, thought to be formed of rock ejected from Mars. This report is also controversial and scientific debate continues. (See Viking biological experiments.)

Animals On Other Planets Speculation And Theory,

Humanoids-On-Other-Planetsincludes Humanoids-On-Other-Planets Origins- Speculations And Scientific Theory Panspermia. Extraterrestrial life Along with the biochemical basis of extraterrestrial life, there remains a broader consideration of evolution and morphology.

Humanoids-On-Other-Planets Technical Civilizations includes Humanoids-On-Other-Planets Technical-Civilizations, Speculation And Theory Astrosociobiology

Humanoids-On-Other-Planets Technical-Civilizations, Migrations Most scientists hold that if extraterrestrial life exists, its evolution would have occurred independently in different places in the universe. An alternative hypothesis, held by a minority, is panspermia, which suggests that life in the universe could have stemmed from a smaller number of points of origin, and then spread across the universe, from habitable planet to habitable planet.

Humanoids-On-Other-Planets Technical-Civilizations, Quantity of Drake Equation

Humanoids-On-Other-Planets-Civilizations On Local Stars includes Search For Humanoids-On-Other-Planets-Civlizations On Local-Stars, SETI

Space exploration

Space Exploration Through Space Travel

Astronautics

Interstellar Travel sciences include Spacecraft Propulsion, and others.

Interplanetary travel sciences include Spacecraft Propulsion, Microgravity nvironment, Space transport, Rocket launch technology, Rocket, Astrodynamics, Unmanned space missions, Manned space missions and others.

Space Station

Space Colonization

Space Colonization Justification includes human spaceflight, Space and survival, Ensure the Survival of Our Species and others.

Space Colony Location includes Colonization of Mars, Mars Society, Colonization of Mercury, Colonization of Venus, Venusian terraforming, Colonization of the Moon, Colonization of the outer solar system, Artemis Project, Europa, Phobos, Colonization of the asteroids and others.

Space Colonization Habitat science includes Space habitat, Human adaptation to space, Manmade closed ecological system, Generation ship, Floating cities, Planetary habitability, Domed city, Ocean colonization, Underground city and other sub-sciences.

Space Colonization Agricultureincludes Biosphere 2 and BIOS-3 and others.

Space Colonization Food Processing includes Space food and others.

Space Colonization Housing includes International Space Station).

Space Colonization Clothing includes Space suits

Space Colonization Construction includes Orbital Megastructures, station-keeping, Amundsen-Scott South Pole Station, Devon Island, Mars Arctic Research Station, Mars Desert Research Station, climate, underwater structures for planets with oceans or very heavy atmospheres and others.

Space Colonization Transportation includes Lunar rover

Space Colonization Materials includes Recycling

Space Colonization Energy includes Renewable energy

Space Colonization General Manufacturing includes Space Manufacturing

Space Colonization Economics includes Space Frontier Foundation , Private spaceflight and space tourism, solar power satellites, Asteroid mining, space manufacturing,

Space Colonization Operations includes space agencies, Space advocacy, Colonize the Cosmos, Artemis Project , National Space Society, Planetary Society, robotic exploration , search for extraterrestrial life, Space Settlement Institute, Students for the Exploration and Development of Space, NASA, ESA, Project Constellation

Space Colonization Law And Protection includes Space Law

Space Colonization Education

Further reading

• Jack Cohen and Ian Stewart (2002). Evolving the Alien: The Science of Extraterrestrial Life. Ebury Press. ISBN 0-09-187927-2.
• John C. Baird (1987). The Inner Limits of Outer Space: A Psychologist Critiques Our Efforts to Communicate With Extraterrestrial Beings. Hanover: University Press of New England. ISBN 0-87451-406-1.
• Donald Goldsmith (1997). The Hunt for Life on Mars. New York: A Dutton Book. ISBN 0-525-94336-6.
• Michael T. Lemnick (1998). Other Worlds: The Search for Life in the Universe. New York: A Touchstone Book.
• Cliff Pickover (2003). The Science of Aliens. New York: Basic Books. ISBN 0-465-07315-8.
• Roth, Christopher F. (2005) "Ufology as Anthropology: Race, Extraterrestrials, and the Occult." In E.T. Culture: Anthropology in Outerspaces, ed. by Debbora Battaglia. Durham, N.C.: Duke University Press.
• Crowe, Michael J. The Extraterrestrial Life Debate, 1750--1900. Dover Publications.
• Sagan, Carl and I.S. Shklovskii (1966). Intelligent Life in the Universe. Random House.
• Sagan, Carl (1973). Communication with Extraterrestrial Intelligence. MIT Press.

External links

• 'Is There Anybody Out There?' Freeview video by the Vega Science Trust and the BBC/OU
• Actual Aliens: Extraterrestrial News and Current Events
• PBS: Life Beyond Earth a film by Timothy Ferris
• PBS: Exploring Space - The Quest for Life by Scott Pearson
• ufoskeptic.org by Bernard Haisch
• Xenopsychology by Robert A. Freitas Jr.
• "What Aliens Might Look Like" from National Geographic
• Sylvia Engdahl , "Early Space Poetry" Part I: Didactic and other poetry concerning other inhabited worlds, well-known and obscure poets, 17th-18th centuries. "Part II": 19th century
• Top stars picked in alien search
• Exclusive: NASA Researchers Claim Evidence of Present Life on Mars - Berger, Brian (2005)
• NASA denies Mars life reports - spacetoday.net (2005)
• A religious (Christian) view about the possibility of alien life existing AnswersDepot.com
• Architects and Outer Space
• Overview of Human Physiology in Space

Category:Space exploration

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

The Mythological Cycle is one of the four major cycles of Irish mythology, and is so called because it represents the remains of the pagan mythology of pre-Christian Ireland, although the gods and supernatural beings have been euhemerised by their Christian redactors into historical kings and heroes. Occasionally though, the mask slips.

The cycle consists of numerous prose tales and poems found in medieval manuscripts, as well as pseudohistorical chronicles such as Lebor Gabála Érenn and the early parts of the Annals of the Four Masters and Seathrún Céitinn's History of Ireland.

The invasions tradition

The Mythological Cycle traces the supposed history of Ireland from its earliest inhabitants before the Biblical flood, through a series of invasions to the arrival of the Goidelic-speaking Milesians or Gaels. Some of these invaders probably represent genuine historical migrations; others, like the Tuatha Dé Danann with their magical powers, are unquestionably degraded gods.

Before the flood

The first inhabitants of Ireland were led by Cessair, a granddaughter of Noah for whom there was no room on the Ark. She and her followers arrived only 40 days before the deluge and were wiped out, all except Fintan, who transformed into a salmon. Through a series of transformations he survived into historical times and told the tale of his people.

Céitinn records a tradition from the lost 8th century Book of Druimm Snechta that Banba was the first inhabitant of Ireland before the flood, but she is more usually associated with the Tuatha Dé Danann.

Partholon (3rd Millenium BC?)

Three hundred years after the flood a new wave of invaders arrived, led by Partholon, a Scythian who had been exiled after killing his parents. In those days in Ireland there were only three lakes, nine rivers and one plain. During his time seven lakes burst from the ground, and he cleared four plains. He brought the first cattle to Ireland.

Three years after he arrived Partholon won a battle against the Fomorians, led by Cichol Gricenchos. The Fomorians, who appear to be the Irish gods of chaos, are unique among the peoples of the Mythological Cycle in that they have no origin - they're just there. However, Céitinn records a tradition that they arrived in Ireland two hundred years before and lived by fishing and fowling - it's possible that this is a memory of Mesolithic hunter-gatherers giving way to Neolithic farmers.

Partholon and his people were wiped out by a plague, all but Tuan mac Cairill, who like Finntan survived through a series of transformations and told their story to St Finnian.

Nemed (Late 3rd Millenium BC?)

After thirty years another Scythian, Nemed, arrived. He fought four battles against the Fomorians, cleared twelve plains and saw four lakes burst, and dug two royal forts. After he died his people were oppressed by Conand and Morc of the Fomorians, having to pay a heavy tribute in produce and children. They rose up against them and destroyed Conand's Tower on Tory Island, off the coast of County Donegal, but as they fought a great battle against Morc the sea rose and drowned them all, except for one ship containing thirty warriors, who left Ireland and scattered to the four corners of the world.

Fir Bolg (2nd Millenium BC?)

The next invaders were the Fir Bolg, who first established kingship and a system of justice in Ireland. One of their kings, Rinnal, was the first to use iron spear-points. They appear to represent a genuine historical people, the Builg or Belgae. They have also been linked with the Basque or proto-Basque people, in that they were "short and dark" and that common traces exist in the genes of modern Irish people.

Tuatha Dé Danann (2nd Millenium BC?)

The Fir Bolg were displaced by the Tuatha Dé Danann or "Peoples of the goddess Danu", descendants of Nemed, who either came to Ireland from the north on dark clouds or burnt their ships on the shore to ensure they wouldn't retreat. They defeated the Fir Bolg king, Eochaid mac Eirc, in the first Battle of Magh Tuiredh, but their own king, Nuada, lost an arm in the battle. As he was no longer physically perfect he lost the kingship, and his replacement, the half-Fomorian Bres, became the first Tuatha Dé High King of Ireland.

Bres turned out to be a tyrant and brought the Tuatha Dé under the oppression of the Fomorians. Eventually Nuada was restored to the kingship, having had his arm replaced by a working one of silver, and the Tuatha Dé rose against the Fomorians in the second Battle of Magh Tuiredh. Nuada was killed by the Fomorian king, Balor, but Balor met his prophesied end at the hands of his grandson, Lug, who became king of the Tuatha Dé.

The Tuatha Dé are undoubtedly degraded gods, and have many parallels across the Celtic world. Nuada is cognate with the British god Nodens; Lug is a reflex of the pan-Celtic deity Lugus; the name of Lug's successor, the Dagda, is explained by the Irish texts as "the good god"; Tuireann is related to the Gaulish Taranis; Ogma to Ogmios; the Badb to Catubodua. Even after they are displaced as the rulers of Ireland, characters such as Lug, the Mórrígan, Aengus and Manannan appear in stories set centuries later, showing all the signs of immortality.

The Tuatha Dé are said to have brought chariots and druidry to Ireland.

The Sons of Míl/ Milesians and (Lugh story)

The Tuatha Dé Danann were themselves displaced by the Milesians, descendants of Míl Espáine, a warrior who travelled the ancient world before settling in Spain. Míl died without ever seeing Ireland, but his uncle Íth saw the island from a tower and led an advance force to scout it out. The three kings of the Tuatha Dé, Mac Cuill, Mac Cecht and Mac Gréine, had Íth killed. After his body was returned to Spain, Míl's eight sons led a full-scale invasion.

After defeating the Tuatha Dé in battle at Slieve Mish, County Kerry, the Milesians met Ériu, Banba and Fodla, the wives of the three kings, each of whom asked them to name the island after her. Ériu is the origin of the modern name Éire, and Banba and Fodla are still used as poetic names for Ireland, much as Albion is for Great Britain.

Mac Cuill, Mac Cecht and Mac Gréine asked for a three-day truce in which the Milesians would stay at anchor nine waves' distance from shore, and the Milesians agreed, but the druids of the Tuatha Dé conjured up a storm to drive them away. However Amergin, son of Míl, calmed the sea with his poetry. The Milesians landed and defeated the Tuatha Dé at Tailtiu, but only three of Míl's sons, Eber Finn, Eremon and Amergin, survived. Amergin divided the land between his two brothers. The Tuatha Dé moved underground, into the sídhe mounds, to be ruled by Bodb Dearg.

See also

• List of High Kings of Ireland
• Metrical Dindshenchas