Is there life elsewhere in the Universe...either microbes or intelligent life?
                             Is there anybody out there? 

Ask most people today, including biology students, and they say YES. 
     A survey in 2017 from 24 countries indicated that about 47% of the respondents
   believe that "intelligent extraterrestrials civilizations exist".

Consider some Human's current common cultural beliefs in aliens, such as...
      UFO's,   crop circles,   Roswell,   the Area 51, &  SETI  &  Very Large Array,
      and movies as:     Contact,  &  Species-trailer,  &  Arrival. 
  
Many a novel or TV show have suggested that UFOs may be alien spacecraft
visiting Earth to observe or to experiment on Human (Area 51  &   Oumuamua ?)
     
Science has no definitive scientific evidence to support such a belief, but
human popular culture (films, TV, novels) is filled with alien creatures.       

  
*                                                                                                   

 
 
 but, Lots of Circumstantial Support for Human's Hunt for Alien Life that includes:  
  
   1. so many stars = a statistical probability of planets like Earth in the Universe,
              Habitable Exoplanets Catalog   &    NASA Exoplanets
  
   2. water (needed for Earth life) worlds do exist in our solar system =
               for ex: moons as Europa, Calisto, Ganymeade, Enceladus all have water
    
   3. Life evolved "quickly"... Age of the Universe estimates are 13.7 billions year old
               Earth forms 4.57 BYA  & 1st fossil evidence of bacteria-life is by 3.5 BYA in
                stromatolites rock formations showing a fossil microbial record from 3.5 BYA.
  
   4. Life thrives in extreme environments (extremophile organisms), as in deep space...  
        ex:  Desulforudis audaxviator - is a bacterium that gets its chemical energy sources 
                     from radioactive decay of minerals, thus it does not require sunlight. It has
                     genes to extract C from dissolved CO₂ and genes for N₂ fixation.
  
   5.SETI - Search for Extra-Terrestrial Intelligence  &  Mount Aricebo Observatory
  
   6. Humans desire "to believe" = Roswell, UFO's,  &  popular SciFi movies...
  
         back

  (Day Earth Stood Still)

A widely held fear of humanity is that an alien encounter would wreck havoc
  and destruction upon us.  What would alien want with us?
       ALIEN MYTHS:
  1. aliens will eat us...   to eat us aliens must be capable of processing our
         molecules (aa's & sugars), requiring a similar biochemistry - not likely
  2. aliens would breed with us (human/alien hybrids)...  we can't even reproduce
        with our nearest evolutionary relative - chimpanzees, not likely
  3. aliens would look like us...  more likely they'd be as different as the
         octopus, which has a high level of intelligence, a decentralized nervous
         system, and likely an alternative style of consciousness, not likely
  4. aliens would be living organisms...  more likely they'd be robots produced
         by aliens- again not likely.
  5. aliens would rob our natural resources (water & metals)...  Earth's metal
         is mostly its iron core. Asteroids would be a better resource as would
         water from icy moons as Europa - no need to mine Earth.
 If aliens do not need what we have (organic molecules, water, etc) why make
      contact with us.... maybe for curiosity's sake. 
             back                    paraphrased from Aliens: The World's Leading Scientists
                                                           on the search fro Extraterrestrial Life,  by Jim Al-Khalili
 

SKIP ALL THE MATERIAL BELOW...
The answer to the presence of life elsewhere in the Universe must come from a judicious
application for the scientific method to the collection of data in support of the premise.

Is this question open to the Scientific Method ???
to some extent yes... Let's see what has been done.

1.  The Search for Extraterrestrial Intelligence - SETI
       assumes alien neighbors are trying to contact us and we should look for them.
       SETI is a research program looking for the evidence of life elsewhere in the cosmos.
       The program assumes that use of microwave radio to communicate between the stars
       may suggest intelligent life elsewhere in the Universe and thus SETI uses large radio
       telescopes, as Mt. Arecibo (pic - Golden Eye) in Puerto Rico & VLA in New Mexico.
       While there have been several false alarms, there has been no reception of a
       non-random, intelligent radio signal. Radio is to slow & in 100 years since Marconi our
       signals have not left our galaxy yet.

           Contact - 1997 SciFi film of Carl Sagan - novel about a SETI contact realized.

 
2.  Other scientific approaches in the field of astrobiology include: 
        
     a.  the study of the origins of the Universe - Modern Cosmology  +  Big Bang
     b.  analysis of meteorites for the evidence of life or its byproducts
     c.  analysis of molecules from space - comets & Origins of Life  +  NASA-Stardust
     d.  telescopic analysis - Hubble telescope  - images - search for "M" class planets
     e.  collection of samples (moon rocks & maybe Martian dust - Pathfinder - Rovers)
                and satellites to the Universe - Voyager, Galileo
     f.  life simulation experiments: extremophiles (microbes in extreme Earth environs)
     g.  is travel to distant stars possible?
                    Space Travel - by current technology (best rockets travel @ 10Km/sec)
                                    might take 100,000 years to reach our nearest neighbor star?
                    Star Trek Warp Engines? - not with our science and physics 
                                    The theoretical energy to move a ship the size of the Enterprise
                                    at just 1/10 the speed of light would be greater than all the heat
                                    energy burned by mankind since recorded history.
      Search for Extraterrestrials - Where are They? Space exploration.

 
3.  So what would aliens really look like - are there anthropomorphic similarities?
   
     Our human view of extraterrestrials have stretched from pets as ALF & Tribbles to
            anthropomorphic models (Jerri Ryan as 7 of 9) similar to the human species. 

     Are these assumptions valid. What might we expect aliens to look like?

         How many eyes would they have?
             2 is a good guess, for it would allow depth perception;   3 might even be better,
             with an eye in the back of the head, one could see where they had been,
             or who was sneaking up to eat them. But, 4 or more eyes could be a neurological
             nightmare, for it could present too much sensory information to process.

         How large would they be?  If ET was twice our average height, it means that they
              would have 4 times the cross-sectional area and thus 4 times the strength.
              Unfortunately, an ET twice as tall would be 8 times as heavy and thus ET's
              power-to-weight ratio would actually be reduced by a factor of 2.
              This argues against such Hollywood greats as "Them" and "Godzilla".                      e2
                                         Michael Shermer YouTube video opinion   &   SA Nov 2009

   Law of Biological Convergence suggests that via the known laws of chemistry & physics,
     aliens & man that evolved under same rules might therefore have similar body morphs...
                                                  (some more ideas of alien form)

     Vatican announces   "It's OK to believe in aliens". ("Doesn't contradict faith in God".)  

     When Columbus landed in America.. "didn't turn out well for Native Amerians"
                    ...so says Stephen Hawking* who suggests aliens might be predatory? 

   Conclusion:    Some scientific questions, while similar to a belief or perception,
                                   are best answered by using the scientific method,
                                   which can gather conclusive evidence of fact.

    Back

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