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ASTRONOMY 112 EXTRA-TERRESTRIAL DEBATE. PRO TEAM. Opening Statements. Earth is estimated to be 4.5 billion years old
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Opening Statements • Earth is estimated to be 4.5 billion years old • Life is the condition that distinguishes organisms from inorganic objects and dead organisms, being manifested by growth through metabolism, reproduction, and the power of adaptation to environment through changes originating internally. • The earliest proof of life on earth is 3.4 billion years old-fossilized mats of cyanobacteria called stromatolites found in Australia, but many scientists believe life could have began as early as 3.8 billion years ago
Do extraterrestrials exist? • Habitable zones: • Goldilocks zone- is the region around a star within which planetary-mass objects with sufficient atmospheric pressure can support liquid water at their surfaces • G dwarfs- similar to our sun with little variance 0.8-1.2 solar masses • M dwarfs- .075-roughly .5 solar masses (Smaller Goldilocks zone, but possible) • Within 33 light years, there are 240 known M dwarfs (Sun )that could serve as suns for potentially habitable galaxies. • The existence of water vapor is an indication that there is some sort of atmosphere • Significant “plumes of water vapor” were spotted recently by scientists via the infrared space telescope that has been set up by the European Space Agency (ESA) at the Herschel Space Observatory.
Do extraterrestrials exist? • Habitable zones: Kepler Mission • Kepler looks at over 100,000 stars for at least 3.5 years • Results • 442 Systems with Multiple Planets
Does ET exist? National Geographic • Over 1700 planets discovered to date orbiting 1033 stars • 16 possible to support life • 0.94% probability • What is 1% of even 1% of all the stars in the universe?
Do extraterrestrials exist? • Drakes equation/Fermi’s paradox: • Within the limits of our existing technology, any practical search for distant intelligent life must necessarily be a search for some manifestation of a distant technology. After about 50 years, the Drake equation is still of seminal importance because it is a 'road map' of what we need to learn in order to solve this fundamental existential question. • Trans-Atlantic radio established 1927 • 1936 Winter Olympics transmission- Hitler was the first to make a radio transmission significant enough (Ironic) • Less than 100 years of transmission compared to 3.4 billion years of life on Earth
Do extraterrestrials exist? Speed of Light Theory: • A coherent group of tested general propositions, commonly regarded as correct, that can be used as principles of explanation and prediction for a class of phenomena • A proposed explanation whose status is still conjectural and subject to experimentation, in contrast to well-established propositions that are regarded as reporting matters of actual fact
Do extraterrestrials exist? Speed of Light In their time “Commonly Regarded as Correct” Theories • “The World is flat.” -1492 • “Humans are not meant to fly.”-17 December 1903 • “Humans will never travel into space.”-12 April 1961 • Etc……
Astrobiology/Biology • Elements of chemical Composition: • The four most common elements in the universe are hydrogen, helium, oxygen, and carbon. The four most common elements in the human body (and really, for most of life on earth) are oxygen, carbon, hydrogen, and nitrogen. The fact that three of these overlap demonstrates how life relies on common elements, not those that are rarer. Assuming that the general ratio of elements in the universe holds true, it would make sense that there are other life forms when a similar combination of elements are in the presence of energy. • The background radiation on Earth is due to the decay of earthly nuclear materials found in the Earth’s crust, but is now be considered to be from debris of extra-terrestrial fission and fusion reactions taken place by the sun of the stats in the cosmos. -The Big Bang made Hydrogen, Helium, and some trace amounts of Lithium -All other elements are made inside of stars through fusion
Astrobiology/Biology • 10 November 2008 Scientists revealed that tiny creatures called water bears (tardigrades) are the first animals to survive exposure to space. Sending water bears into space is one of several ESA experiments looking at organisms which can survive longer periods in open space. • Tardigrades can withstand temperatures ranging from -272 deg C(-457 deg F) to +150 deg C(302 deg F), they can be without water for a period of 10 years, and they are extremely resistant to radiation. • Life finds a way to survive whenever survival is possible whether we can fathom it or not.
What does this mean for us • Elements of chemical Composition: • The four most common elements in the universe are hydrogen, helium, oxygen, and carbon. The four most common elements in the human body (and really, for most of life on earth) are oxygen, carbon, hydrogen, and nitrogen. The fact that three of these overlap demonstrates how life relies on common elements, not those that are rarer. Assuming that the general ratio of elements in the universe holds true, it would make sense that there are other life forms when a similar combination of elements are in the presence of energy. • 1976, The Viking Mars landers detect chemical signatures indicative of life. Tests performed on Martian soil samples by NASA's Viking landers hinted at chemical evidence of life. One experiment mixed soil with radioactive-carbon-labelled nutrients and then tested for the production of radioactive methane gas. The test reported a positive result. The production of radioactive methane suggested that something in the soil was metabolising the nutrients and producing radioactive gas. • In, 2002, Chemical hints of life are found in old data from Venus probes and landers. Life in Venus' clouds may be the best way to explain some curious anomalies in the composition of its atmosphere, claimed by the University of Texas astrobiologists in 2002. Solar radiation and lightning should be generating masses of carbon monoxide on Venus, yet it is rare, as though something is removing it. Hydrogen sulphide and sulphur dioxide are both present too. These readily react together, and are not usually found co-existing, unless some process constantly is churning them out. Most mysterious is the presence of carbonyl sulphide. This is only produced by microbes or catalysts on Earth, and not by any other known inorganic process. Venus's conditions 50 kilometres up in the atmosphere are more hospitable and moist, with a temperature of 70°C and a pressure similar to Earth.
Closing Arguments Technology • Babbage & son (1833) • Intel introduced its first 4-bit microprocessor 4004 in 1971 • First cellphone-1973 • First smartphone sold in 1993 • Iphone(4GB)-2007 • Iphone(64GB)-2014 Space • Moon landing- 20 July 1969 • Mars 2&3 probes- 1971 • Sojourner- 4 July 1997 first successful Mars rover landing
What creates life? • I cannot conclude that I should be so ignorant as to think that humans are the only intelligent beings in the vastness of our universe. • I refuse to believe that life only “rolled the dice” once and we are the best thing it came up with.