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Implications of the Search and Discovery of Life in the Universe HNRT 228 Bennett & Shostak FALL 2015 Dr. H.Geller 1 Issues to be Discussed • Is There Life Elsewhere – Is life likely – Prospects for finding life • In our Solar System • Elsewhere in the universe • ET and Humans – What impact contact would have? • Examples from our own past – Is the search significant? • If life found or not? 2 Remember what is astrobiology? • Life in the Universe – Origins – Development – Distribution – Search 3 Life Seems Likely • What is needed for life? – Right chemical elements – Right environmental conditions • Especially for liquid water – Right amount of time • Without heavy meteor bombardment • With right elements and conditions • Where are these conditions found? – Around individual stars throughout galaxy 4 Where to look in Solar System? • Remember likely candidates – Mars • Perhaps life in past – Europa • Perhaps life in subsurface ocean – Titan • Perhaps life in “oceans” beneath cloudy atmosphere 5 Where to look in galaxy? • Disk region of galaxy – Population I stars that have access to heavy elements during formation • Star like our Sun worked at least once • Individual stars – F, G, K most likely for habitable zone over a long enough period 6 How will we view contact? • General public – Many already believe that ETIs are among us or contacted us in the past or today – “I told you so” attitude may arise • Government – Nations to make treaties with ETIs • Scientists – Let’s study it 7 Types of Contact • Communications – Radio waves – Other portions of EM spectrum • Artifacts – Remains of space craft – Actual spacecraft • Face to face – What language would they speak? 8 Response to Contact • Nine principles – Seek to verify evidence – Alert other research organizations – Messages to IAU and UN under Article XI of the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space – Disseminate detection “promptly, openly, and widely” including the media 9 Response to Contact (cont’d) • Remaining (of the nine principles) – – – – – Release data for confirmation by others Confirm and monitor more data recordings Stop all noise at appropriate frequencies Do not send a response signal Advise and consult with other international organizations as to the procedure for further actions 10 Consider Your Reaction – iClicker Questions • NEWSFLASH: Scientists Confirm They Have Received Message From Another Intelligent Civilization In The Galaxy – Would you change your religion? •A •B •C Yes No Not Sure 11 Consider Your Reaction – iClicker Questions • NEWSFLASH: Scientists Confirm They Have Received Message From Another Intelligent Civilization In The Galaxy – Would you change your nationality? •A •B •C Yes No Not Sure 12 Consider Your Reaction – iClicker Questions • NEWSFLASH: Scientists Confirm They Have Received Message From Another Intelligent Civilization In The Galaxy – Would you change your lifestyle? •A •B •C Yes No Not Sure 13 Consider Your Reaction – iClicker Questions • NEWSFLASH: Scientists Confirm They Have Received Message From Another Intelligent Civilization In The Galaxy – Would you quit school? •A •B •C Yes No Not Sure 14 Consider Your Reaction – iClicker Questions • NEWSFLASH: Scientists Confirm They Have Received Message From Another Intelligent Civilization In The Galaxy – Would you commit suicide? •A •B •C Yes No Not Sure 15 Explorations of the Universe: Another View Encyclopedia Galactica 16 “Extraordinary Claims Require Extraordinary Evidence” - Carl Sagan 17 Close Encounters • First Kind: Sighting • Second Kind: Physical Evidence • Third Kind: Human-ETI Meeting 18 UFO California, November 1896 19 UFOEngland, March 1909 20 Lessons From Early UFO’s • Both are exactly what people around 1900 would have expected aircraft to look like • Consider: – If ETIs are trying to conceal their presence by using terrestrial-style ships, why are they using searchlights? • Consider: – If we have effective night-vision devices today, why would an advanced ETI need searchlights? • Consider: • people saw a light (Venus, an airplane, a balloon, etc.?) • and subconsciously added details 21 Near Miss, August 10, 1972 22 1972 Near Miss • Object was about the size of a bus • Entered Atmosphere over Utah, travelling north, exited over Canada • Velocity 15 km/sec • Missed by 58 km 23 Returning to Space 24 Lessons From a Near Miss • • • • Completely unexpected Crossed sparsely-inhabited region Visible a total of 101 seconds Visible no more than 30 seconds at any one spot • We have dozens of clear photographs of this event. 25 The Drake Equation “A wonderful way to organize our ignorance” - Jill Tarter 26 The Drake Equation: Another View Number of Intelligent Civilizations = Number of Stars in the Galaxy (400 billion) x Fraction of Stars with Planets (1/4?) x Number of suitable planets per star (2?) x Fraction of planets where life appears (1/2??) x Fraction of planets with intelligence (???) x Fraction of planets with technology (???) x Fraction of planet’s life with technology (???) 27 So Where Are They? • Populations expand exponentially • It would take an exponentially-growing civilization only a few million years to fill the Galaxy, even at sub-light speeds • 2 to the 40th power is over a trillion • If it takes 10,000 years for a colony to achieve interstellar travel, 40 doubling times is only 400,000 years. • So why aren’t they all around us? – Recall the Fermi Paradox 28 Is There A Problem? • What is ETI psychology? – How well do we understand humans? – Will ETIs be belligerent or altruistic • Why did it take us so long to develop technology? – Why did many civilizations never develop technology? • Maybe we’re first? – Someone has to be the first civilization in the galaxy. • Maybe we’re unique? – But does uniqueness imply solitary? 29 What is Astrosociology? • Simply put, a combination of astrobiology and sociology – Multidisciplinary science & humanities course • “Extraterrestrial Altruism: Evolution and Ethics in the Cosmos” edited by Doug Vakoch of the SETI Institute – Chapter 5 by Dr. Harold Geller • Harmful ETI Hypothesis Denied: Visiting ETIs Likely Altruists 30 Other Stuff For the Drake Equation • Jupiter Stabilizes Solar System – Evidence for this with most recent Kepler data • Jupiter lessens impact bombardment – Evidence for this with models using Kepler data • Moon stabilizes Earth’s axial tilt – Physics tells us this • Earth’s magnetic field deflects cosmic rays – This is a fact, and mutations are affected • Liquid Water Zone is narrow and changes with time as stars brighten – Demonstrated from basic physics • Center of the Galaxy Deadly? – Amount of x-rays leads us to believe this is true. 31 Communicating With Earth’s ETIs • • • • Rosetta Stone, 1799 Champollion, 1828 Three Parallel texts, one in Greek Can we decipher languages with no parallel texts? 32 Cuneiform Georg Friedrich Grotefend (1775-1853) • • • • Wedge-shaped markings in clay Simple, hence not pictographs Found literally by the millions Seem to be mundane records, official documents, etc. • Probably Semitic language 33 Cuneiform • Official documents probably had a standard format: “King ---, son of ----”, etc. • Guess words for “king” and “son” • Create genealogy • Compare with genealogies in other documents and match format • Assign sound values to letters • Guess many other words from known Semitic languages 34 Cuneiform “Empires may rise and empires may fall, but bureaucrats are the same forever.” 35 Mayan Heiroglyphs • Diego de Landa, 1566 • Responsible for destruction of much of Mayan literature • Left detailed account of Mayans at time of conquest • Described 64 hieroglyphs, equated 30 with letters • Later researchers identified 400-800 • Once regarded as a type example of a language lost beyond recovery • Heinrich Berlin, 1958: -Locality signs • Tatiana Proskouriakoff, 1960 36 - Ascension and Reign signs Mayan Heiroglyphs • Yuri Knozorov, 1960 • De Landa was too good an observer to be totally mistaken • His “letters” were really syllables • Positional statistics to analyze syntax • Maya hieroglyphs are now over 85% decipherable • Maya were not as one-dimensional as once thought 37 What if we succeed? Some Features of Culture Shock • • • • Loss of Faith in Beliefs and Institutions Xenophobia Over-Dependence, Copying Nihilism 38 Arthur C. Clarke’s View • The only way to test the limits of the possible is by going beyond them into the impossible – A Agree B Disagree • When an elderly but distinguished scientist says something is possible, he is probably right. When he says something is impossible, he is very likely wrong – A Agree B Disagree • Any sufficiently advanced technology is indistinguishable from magic – A Agree B Disagree 39 Shall We Hide? A Yes B No • Stephen Hawking believes so – http://www.timesonline.co.uk/tol/news/science/spa ce/article7107207.ece • Others have other opinions – http://journalofcosmology.com/Aliens100.html • At radio frequencies – Earth is brighter than the Sun – Signals now 100 light years out • ETIs could determine – Length of our day and year – Size of Earth, Distance from Sun – Draw a crude map of Developed World 40 Our Views of ETIs • Post World-War II – “Savior Model” – “Hostile ETIs” - Eat or Enslave • Science Source of Fascination and Fear – Winning World War II – Nuclear War • Similarity with Westerns – We’re the Good Guys – Fighting off Hostile Threats 41 Our Views of ETIs Evolve • 1960’s: Hostile ETI films and Westerns both decline • We’re Not Always the Good Guys – – – – Historical Revision of Frontier “Spaghetti Westerns”-Dark and satirical Civil Rights Movement Vietnam • Star Trek, 1967 – Enlightened, Optimistic Future 42 Variations • Humans as Helpers: E.T. • Encounter as Wonder: Close Encounters of the Third Kind • Encounter as Dreary: Contact • Swashbuckling: Star Wars • Satire: Men In Black • Return to Hostile ETIs – Star Trek Spinoffs (The Borg, the Dominion) – Independence Day 43 SETI@Home http://setiathome.ssl.berkeley.edu/ 44