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astro20 chap27 - Las Positas College
astro20 chap27 - Las Positas College

... fraction of planets with intelligent life that develops technology – don’t know how many early human civilizations failed to develop technology – the fact the many independent early civilizations did develop technology makes us believe ~ 1 ...
Extra-Solar Planets
Extra-Solar Planets

... Edward Teller Herbert York Emil Konopinski ...
Intelligent Life in the Milky Way Galaxy
Intelligent Life in the Milky Way Galaxy

... Individuals with traits that best allow them to survive and reproduce will on average produce the greatest number of surviving offspring. ...
There are numerous other ways in which human civilization could
There are numerous other ways in which human civilization could

... Biologists have studied the species migration ...
Is there anybody out there?
Is there anybody out there?

... • Cellular organization • Inheritance/Reproduction • Metabolism ...
Implications of the Search and Discovery
Implications of the Search and Discovery

... • 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 ...
File
File

... • Can be estimated by dividing current number of stars in Galaxy by the 10 Ga lifetime of our Galaxy. • We obtain a formation rate of 10 stars ...
File
File

... • Many experiments have been done in which energy has been applied to a mixture of compounds found in atmosphere of early Earth. • These experiments have created amino ...
Day_39
Day_39

... civilization capable of IS communication at some time has arisen. • fnow -Fraction of habitable planets with civilization now, not in the past. ...
25drake6s
25drake6s

... R* = Number of stars in the galaxy fp = ne = Average number of suitable planets per star fl = Fraction of suitable planets on which life evolves fi = fc = Fraction that can communicate fL = Lifetime of civilization / Lifetime of star ...
Where Is Everybody? - Center for Peripheral Studies
Where Is Everybody? - Center for Peripheral Studies

... Where is everybody? The theoretical physicist Enrico Fermi posed this question some fifty years ago (in what has become known as the “Fermi Paradox”), at a time when the scientific community was still reeling from the discoveries of Edwin Hubble and his two hundred-inch telescope. Through that instr ...
Blinn College Department of Physics
Blinn College Department of Physics

... Most of the factors are highly uncertain. Possible results range from 1 communicative civilization within a few dozen light years to us being the only communicative civilization in the Milky Way. ...
Document
Document

... - probably not unique or necessary - probably common - even one third of all stars is a huge number. - no reason to think that such events would not occur ...
Where a limit?
Where a limit?

... covered with a cloud of a dust and gases rotate also. ...
Johnnie French Lab 1
Johnnie French Lab 1

... o Seti – Search for extraterrestrial intelligence. According to www.seti.org their mission “is to explore, understand and explain the origin, nature and prevalence of life in the universe.” o Fermi Paradox – The contradiction between high estimates of intelligent life in the universe and the lack of ...
33_drake
33_drake

... spectrum. Here natural noise is relatively small. Radio communication over interstellar distances is feasible with present technology! ...
life
life

... •We have the ability to destroy civilization •We are also damaging our environment •We are using up non-renewable resources •Civilizations may “mature” – some evidence •Sustainable civilizations is technically possible ...
25drake3s
25drake3s

... Even intelligent life may not be able to communicate ...
Lecture 27 (pdf from the powerpoint)
Lecture 27 (pdf from the powerpoint)

... •Estimated by Drake as 0.5. It is now known from modern planet searches that at least 10% of sunlike stars have planets, and the true proportion may be much higher, since only planets gas-giant size and larger can be detected with current technology.[3] •ne = Estimated by Drake as 2. The same paper ...
astronomy final exam - Physics and Astronomy
astronomy final exam - Physics and Astronomy

... What is the characteristic molecule called which carries the code of LAWKI? What are it's properties? What would best be the best means of communication between other intelligent species in the galaxy and us? A cell's DNA molecules are constructed of what materials? What is the water hole? If our ra ...
Where Are They?
Where Are They?

... If the machines travel at a speed of nc (n<1), then they will visit very star and planet in the galaxy is a time given by Rg/n, where Rg is the radius of the galaxy in light years. Rg ~ 100,000 ly for our galaxy. For n = 0.01, every star will be visited in <107 years. (We have reached n=0.0001) ...
Life: Definition, Origin, Criteria
Life: Definition, Origin, Criteria

... • The SETI project to search for radio signals from outer space ...
Life: Definition, Origin, Criteria
Life: Definition, Origin, Criteria

... • The SETI project to search for radio signals from outer space ...
Life: Definition, Origin, Criteria
Life: Definition, Origin, Criteria

... • The SETI project to search for radio signals from outer space ...
Document
Document

... He is a member of the National Academy of Sciences where he chaired the Board of Physics and Astronomy of the National Research Council (1989-92). Frank also served as President of the Astronomical Society of the Pacific. He was a Professor of Astronomy at Cornell University (1964-84) and served as ...
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Fermi paradox



The Fermi paradox (or Fermi's paradox) is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations, such as in the Drake equation, and the lack of evidence for such civilizations. The basic points of the argument, made by physicists Enrico Fermi and Michael H. Hart, are: The Sun is a typical star, and there are billions of stars in the galaxy that are billions of years older. With high probability, some of these stars will have Earth-like planets, and if the earth is typical, some might develop intelligent life. Some of these civilizations might develop interstellar travel, a step the Earth is investigating now. Even at the slow pace of currently envisioned interstellar travel, the Milky Way galaxy could be completely traversed in about a million years.According to this line of thinking, the Earth should already have been visited by extraterrestrial aliens though Fermi saw no convincing evidence of this, nor any signs of alien intelligence anywhere in the observable universe, leading him to ask, ""Where is everybody?""
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