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Thursday, September 23, 2010

2.6g Life, Intelligence & Civilizations in Universe/Colonization of Moon & Mars

Physician's Notebooks 2  - http://physiciansnotebook.blogspot.com - See Homepage
 Reading the following section may increase your scores on tests - IQ, SAT, MCAT, TOEFL - and get you a free or very low cost education scholarship. It will also make you a more cultured person.
Update 18 October 2018

2.6g: Other Life, Intelligence and Civilizations in Universe; Space Exploration, Colonization of Moon & Mars
Somewhere out there in Universe almost certainly exist solar systems with, perhaps, a planet like Earth, one or a few of which evolved life, some of it intelligent, and, maybe, with civilizations. The 1969-72 Apollo Moon Program had men on the moon. As the success of the 2014 unmanned Mars Rover landing on Mars showed, had the U.S.intelligently continued the Apollo program instead of stupidly squandering money on losing the unnecessary Vietnam War and then getting involved in the unnecessary and criminal (The USA the criminal) Iraq and other Middle East Wars, we would now be seeing a thriving human base on the Moon and manned exploration on Mars.

Colonization on the Moon and Mars in addition to many other benefits for humanity will be an outlet to escape today's brutal instability in our social system. It will also give an escape route for humanity's overpopulation that is subjecting civilization to the runaway global warming from build up of fossil-fuel gases in our atmosphere. And also protect from the not improbable accident of an asteroid smashing into Earth.  
Overarchingly, space exploration will liberate the minds of youth for an adventure greater than the 1492 discovery of the New World. It will give opportunity and challenge for new ambition and a grandly exciting adventurous future. In the immediate future, space exploration and colonization should be a leading priority and may affect every human life.

Size and Structure of Universe

Our position in space starts with Earth, third planet of 9 planets in the Solar System of Sol (the common name for our Sun), a medium-size-and-age sun and star in our Galaxy. A galaxy is a localization of over 100 billion stars. Universe has many billions of galaxies of sizes, shapes and ages. The spaces between galaxies are much greater than the galaxies' diameters. The size of Universe in diameter is measured by furthest stars 14-billion light years out and since light travels in one second's time c.186,000 miles or 300,000 kilometers, it is a huge distance.
  
                                     
                 A galaxy like ours: The bright area is the 100-billions stars packed together. The surreal eye, of course, is a drawing.

 Ours is a spiral galaxy relatively flat and most of its stars lie in the thin plane of the galactic rotation. Viewed from front, it looks like a 4-arm propeller. Its stars are most packed together at center, which is like the nose of the propeller. Our sun, Sol, is 2/3rds out, and it rotates with the galaxy at 1 km per second (3600 km, or 1100 miles per hour). At this rotational speed and from Sol's location, it takes c.220-million Earth years to make a revolution. This is a galactic year. Since we estimate Galaxy to be 4.6-billion years old, our sun is c.21 Galactic years of age.


We Are in Constant Motions
Think of yourself as you are now – one person; on surface Earth that spins on its axis like a top, in a counterclockwise direction, if viewed from above its north pole. The spin we are in carries us from our west to east. The next motion is Earth's around Sol, counterclockwise, viewed from above the revolution. Then comes rotation by Sol spinning on its axis (counterclockwise viewed from its north pole). Then Sol's movement as part of its rotating galaxy. Then Galaxy's movement in Universe influenced by the initially creative Big Bang, which flung all matter outward as explosion, and also Galaxy's movement influenced by gravity-pull from other galaxies. The resultant of all these movements would predict each person's movements. This should make readers aware of the dynamism of Universe. That we are unaware of it is because of our atmosphere's damping its effect and because Earth's gravity fixes us in place against the ground.
   The picture is one in which we live in a dynamic universe filled with evolving cosmic objects. And everything is constantly in change: clouds of gas and dust and galaxies develop; stars appear, grow, die; life appears; and, perhaps, becomes intelligent and flourishes into civilizations; and all may be extinguished as the environment changes unfavorably. So today, we see Universe filled with planets, stars, galaxies, which, on the immense cosmic time scale, are brief, forming, flickering and fading, lost forever in space and time. And somewhere out in space may be other life forms, some intelligent, and a few of these in civilizations like ours or more advanced.
   The human individual lifespan and the lifespans of technological societies in the 14-billion year old Universe, plus its dynamic evolution plus the known example of what happened in our case make other life and civilizations with advanced technologies out in space highly probable. Given the hugeness of Universe and the vast intervals between galaxies and stars the big question is: If other civilizations have developed, can they and if so will they ever contact us or we them?

The Interstellar Medium (ISM)

is gas and dust distributed unevenly throughout Galaxy. The dust grains are 10-4 to 10-5 cm diameter. (Minuscule) These grains reduce light transmission in the Galactic plane where they are concentrated. The grains are built up by low-energy atoms/molecules collisions. An energetic collision vaporizes the grain to gas. The HI atomic particle (Hydrogen composed of single electrically neutral atom, not the usual double atom molecular hydrogen we know on Earth) is the primary marker of the ISM and it gives the most famous spectral line in astronomy, the 1,420 megahertz (1420-million waves per second) radio frequency, 21 cm wavelength line. 

About the 21 cm Wavelength Radiation of HI:

Before its source was understood, a radio 'hiss' coming from the center of our galaxy was noted that varied on a daily cycle. This was in 1940; in 1944 it was predicted that neutral mono-atomic hydrogen could produce radiation at a frequency of 1420 MegaHz due to two closely spaced energy levels in the ground state of the hydrogen atom. A radio emission at a frequency of 1420 MegaHz, computes to wavelength of the 21 cm "radio hiss" in the microwave spectrum.
This 21-cm radiation line pervades all our space. In the search for other civilizations, any technological civilization would detect it as we have within 100 years after developing radio and telescopes. So its attention-calling characteristic could be used as a vehicle for a universal language, mathematics and number system.

Evolution of Stars and Life & Death of the Sun

Our sun, Sol, is c.4.6-billion years old. Its fuel of heat is the 4 Hydrogen into 1 Helium fusion reaction. It has another 8-billion years to shine
 with gradually unstable luminosity in Main Sequence. But, even before then, life here will face big problems.

Evolution of Inter-Stellar (IS) Gas Mass into a Star
Clouds of gas and dust condense due to gravitational attraction and they fragment into smaller parts and from each a cloud of nuclear mass is formed - a proto-star - high-volume, low-density, opaque and relatively low-temperature. Seen by telescope it is a dark body against surrounding light background of stars. It is believed that planets form around proto-stars at this stage.
   As time goes by, the proto star contracts further. It tightens into smaller volume, its interior and surface temperatures rise. The star now enters Main Sequence (MS from here meaning stars that evolve smoothly as luminosity decreases)
   The contraction phase of a star of solar mass begins at high-luminosity (1000 times brighter than Sol's). But its Luminosity (L) declines rapidly and in a few million years (a metaphoric eye-blink on cosmic time scale) it has the present Sol's Luminosity. It takes c.100-million years to enter Main Sequence as low-density high-luminosity red giant. The temperature in the star's interior has now become high enough for thermonuclear reaction. The pressure of the gaseous interior at this point balances the gravitational attraction, the gaseous sphere stops contracting, and a star is born!

After the star enters Main Sequence, its temperature and luminosity (L) stay relatively stable over a long period, as has been the case for Sol, which has only increased in L by 20% in the last 5-billion years. 
   A star's initial mass determines its lifetime. If the mass is great, the inner temperature is very high, and the sun becomes a powerful source of radiation but rapidly depletes its supply of Hydrogen fusion fuel. Thus, stars with masses 20 times or more greater than Sol – hot blue giants of spectral class O – remain on Main Sequence only a few million years but suns with masses close to Sol's will stay on it 10 or more billion years. This is important for development of life in a solar system. The O-class stars do not have enough time for it.

   What about our Sun, Sol? It is c.5-billion years old on the Main Sequence, stably reacting. But how long will this be going on? 
   Three- or 4-billion years from now, Sol's luminosity and radius will start to rise sharply and it will become a red giant star. The red giant will last several hundred million years; then, by exploding as a nova, our by-then gigantic red Sun will discard its atmosphere and become a white dwarf. At Sol's change to red giant, our Earth will be burnt to a crisp. Much before then, life on Earth will face big challenges. So humanity must start to get out into space to colonize new worlds to live on!

 All stars do not pass through the normal stages of development along the Main Sequence and off it. Certain stars explode early as supernova. Their luminosity suddenly increases 100-million times.  
   The Crab Nebula is an important supernova (SN) remnant dating from 1054 AD when the Chinese recorded seeing its appearance. It is an intense source of radio-frequency wave radiation, obviously not artificial because it is spread over a wide range of radio frequencies. Supernovas are the source of the cosmic rays. In addition, to the radiation, these explosions enrich the interstellar medium with the heavier elements. This is very significant for the evolution of stars and for Galaxy as whole as well as for life in the Universe!
   
   Could a supernova have exploded relatively close to our solar system during Earth’s history? Yes.
   Astronomers estimate once in 750-million years is the average of Earth’s encounter with a nearby supernova as it explodes. And that computes, given the solar system's age, to 6 close encounters,

What effect relatively close to Earth? The supernova's brightness at night would be a million times brighter than the brightest star, Sirius; it would light up dark countryside. The flow of ultraviolet radiation would increase by a factor of 10 on Earth. 

   Such a SN would reach us as an expanding mushroom of gas after about 1,000 yrs. Then, during several 10's of thousands of Earth years our Solar System would be embedded inside a “radio nebula” of its materials.
   On Earth, the cosmic ray intensity would increase in wavelike fashion, waxing and waning. The mutation rate of living things would be increased in proportion to increase Cosmic Radiation (CR).
   At present, the background ionizing radiation has 0.4 roentgens from Cosmic Rays (CR). If the CR increased 20 times, as might happen, and probably has several times by now given the age of the Earth) with a nearby supernova, the average radiation dose at surface of Earth would be ten times more than today’s. The life forms that are highly specialized in narrow environmental niches would have a tough time surviving after a thousand or so years of 10x cosmic radiation.

The question of supernova plays an important role in intelligent life in Universe because it might destroy a civilization. An Earth civilization would have 1000 years warning in which to prepare for the worst. The importance of space travel research and space colonization here should be obvious. But a supernova's heavy elements are the materials needed to produce stars like Sol that could also speed evolution to intelligence and civilization.

Timescale of origin of life on Earth: Formation of the planet Earth was 4.6 billion years ago (bya). Earth's surface must have been quite hot during planet formation. By several hundred million years after, the surface temperatures were below 100C (boiling water), and atmosphere and ocean had been out-gassed from interior. The atmosphere then was of a chemically reducing type (reactive electron-rich; Methane CH4 and Ammonia NH3) and it set the stage for the origin of life. The first life may have evolved as early as 4-bya as DNA or RNA with protein molecules. A billion or more years later came virus and bacteria. Single-cell protozoa appear in rocks of 1 bya. But it was not until 0.6 bya that large amounts of oxygen from photosynthetic bacteria give evidence of the diversification of animals and led to today's 21% oxygen atmosphere.
   Picture the primitive Earth 4 bya: its out-gassed, reducing oxygen-free atmosphere and its oceans; the major tectonic changes (movements of Earth’s crust) forming continents; and temperatures warmer than today's. During storms lightning will be flashing frequently and, during days UV light penetrates to water surface and is absorbed in superficial ocean layer. The atmosphere is methane, ammonia, water vapor. The ammonia dissolves in the water, making the oceans alkaline. Due to chemical interactions the air has a little aldehyde and HCN (cyanide) and the oceans have amino acids. No life. What next?
   Experiments done by sending electricity or UV rays into a simple watery solution in a reducing atmosphere of methane and ammonia have resulted in the formation of complex carbohydrates, fats, proteins and purines & pyrimidines (the bases of DNA). Adding phosphate to this mix and further irradiating has resulted in simple DNA molecules. Thus, the first DNA and protein molecules could have been formed spontaneously from non life.
   A number of molecules, like ATP (Adenosine triphosphate the main energy exchange molecule of living things), that are presently part of metabolic cycles, were originally probably formed freely and taken up by earliest living systems.
    The idea that inorganic microsphere-like bodies in early oceans were prototypes for first cell structures is a good one.
                                             Time Lines
100 yrs:  Human individual lifespan 
200 yrs:  Our technologically advanced society has existed
5000 yrs: Civilization's age
50,000 yrs:  tool making intelligence developed
100,000 yrs:  our species Homo sapiens approx. age
4,000,000,000 (billion) yrs ago life begins on Earth 
4.5- to 5-billion yrs ago:  Earth & Sol with Planets form
10-billion yrs ago: our Galaxy is forming
14-billion yrs ago: Universe by Big Bang
If we consider a human generation 33 yrs, we humans are now 3000 generations since the first Homo sapiens. And it took almost all that time to go from species origin to techno society capable of embarking on space exploration, colonization and communication with ExtraTerrestrials (ET). If we assert we are an average case of intelligent life in Universe & Galaxy, we may assume the average ET intelligent species needs c.100,000 years from first appearance to develop space exploration and ET communication capability. Further, we may assume that for such ET to exist now would need a stably shining sun with habitable planet(s) at least 4- to 5-billion years old. 
   Since we know our Galaxy is 10-billion years old and since Homo sapiens has only been capable of ET communication and space exploration for less than 100 years now, it follows that if there are other ET civilizations, they must be vastly in advance of our own. Thus, communication would have a big affect on the lives of all humans. But what that effect would be - good or bad - is unclear. But too late to go back! Our first popular radio and TV have been announcing our presence to potentially listening ET for nearly 100 years and our Voyager spacecraft are now beyond the limits of our solar system, broadcasting a message of our presence.
                                  ET Communication
  ET communication is dealt with very exactly by I.S. Shklovsky and Carl Sagan in their now classic and still best in the field, Intelligent Life in the Universe (1966 and available on Amazon.com). Here I briefly summarize and comment.
   ET communication could be by radio, by light ray as laser beam, or by space vehicle operated by the ET or automated. With radio or light the time limitation is the speed of light c.300,000 Kms (186,000 miles) per second. Since it has been estimated that there is almost no likelihood of intelligent life within 1000 light years of Earth, a message from an ET is going to take more than 1000 years for one way; and if we want to reply, it will be a very slow conversation. Thus we are left with an ET civilization wishing to send us a one-way message. That still leaves inadvertent, unintended messages, which might simply be a signal we might interpret as evidence of intelligent life. It is why we should at least continue the present SETI (search for ET intelligence).
   Finally, a space vehicle, probably automated, its limiting speed up to 0.1% the speed of light. And, in fact our civilization has done that with Voyagers 1 and 2 that now have left our solar system, heading out into interstellar space.

Space Exploration and a colony on the Moon is feasible since the 1969-72 Apollo Moon Program when we showed we could land and sustain humans on another planet. And especially since the perfect landing of the automated Mars probesA manned exploration of Mars followed by colonization is now only a question of will, which should involve resources and decision on the priorities of our civilization.
   Initially the concentration of effort will be to establish a base on the Moon (Luna) and the base will be a jump-off for exploration of Mars.
   Luna is airless with temperatures, for us, unbearably hot and cold. Its first base will be a big rocket vehicle that could house astronauts with oxygen, food and water. The location would be chosen with a view of its use as a base for Mars rockets. It would be at the visible edge of the Moon to preserve radio contact with Earth.  
   Initially the big rocket/temporary base would be landed and contain a shuttle on which astronauts could travel back and forth between the Moon and Earth. Over the next years unmanned rockets carrying parts of the permanent Moon base and other necessary supplies could be landed in vicinity and base construction would begin.
   The permanent base will be a transparent plastic overhead bubble dome sealed hermetically and designed to contain an artificial atmosphere and control its dome's transparency to sunlight and vary the inside temperature. It would be in smaller pieces for transport and then assembled and built up at site. Initially a transported Earth atmosphere and water would be pumped in but quickly oxygen and water could be produced from underlying Moon soil and rock. An atmosphere equivalent to 8000 feet altitude on Earth could serve nicely. (The relatively low pressure and lower oxygen content would improve colonists' heart and lung function, and the longevity factors harmed by the present too much oxygen) This base could be built to house 10 colonists. It would take a several-year effort. Much scientific research on lunar conditions and other astronomy would be accomplished but the main aim would be preparing Mars exploration. The lessons learned building and manning the Moon base will be those we need for building a Mars base because Mars presents a similar problem (not as difficult conditions as on Moon but longer journey). My guess is that the combined Moon-Mars program should take 10 years to reach a stage of completion where we could have regular shuttle flights to Moon and Mars and start to enlarge our bases and move toward colonizing. Overall the program should involve a century of initial effort and envisions a united human society. (But given the disorganized state of Earth today, who could say when it actually, if ever, would be done)
   That is as far as one may write. The rest is up to you, the new and coming generation. As the spokesman at the end of HG Wells's prescient 1936 movie

{Things to Come - 1936 - H.G.Wells - Classic Movie - YouTube (Click it to view)}

 says when the first Earth rocket is poised for take off while an ignorant anti-science mob crashes the gates "Will it be this?" (Anti-science) "Or that?" (The stars).


Note: If this interests you, click, separately, 2.(34-43) The End of Our World, 2.(80-82) The End of Us All , 3.(15-19) Seminar 2 - Intelligent Life in the Uni... , 12.45 Seminar 3 - Moon & Mars Colonization and read each at leisure.
       End of Section. To read on now, click 2.6g-1 Measurements in Science


































































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