SETI: the Search for Extraterrestrial Intelligence

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SETI the Search for Extraterrestrial Intelligence
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What we will look at

• Overview of the topic
• Brief review of exploration in our solar system
• The problem of SETIthe search for
  extraterrestrial intelligence
• Historical, current and planned searches
• Efforts to transmit
• Why have we not found ET?

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The search for respectability
International Astronomical Union created a
Commission on ETL in 1982
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Long of Interest
Poster from 1800-01
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Intelligent Life Here?
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Venus too hot?
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Our Moon
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Mars
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Arm scooped soil and placed in growth chambers
Results nothing certain
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Life from Mars?
Current Rovers looking for water
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Jupiter or Saturn?
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Maybe on one of the moons?
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Beneath the ice on Europa?
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Beyond our Solar System we turn to the stars
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Can they exist?
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How does life begin? The Miller-Urey Experiment
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Beta Pictoris early evidence of other solar
nebulae
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Other planets?
Now more than 200
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We will look in the radiowhy?
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The Water Hole
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First search at Greenbank, WV
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Project Ozma

• 1960
• 200 hours observing two nearby solar stars in
  21-cm
• nothing found but a secret satellite

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85-ft Harvard Dish
Paul Horowitz
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Suitcase SETI
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NASA thinks big Cyclops
Details
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A thousand 100-meter dishes

• detect ETs broadcast, if within 100 ly
• (gt6,000 stars)
• 5 billion

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NASAs nemesis
William Proxmire, Senator from Wisconsin Golden
Fleece Awards Called off by Carl Sagan
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NASAs initial hardware
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Software see a pattern?
This is a plot of signal (intensity of dots) in
frequency vs. time
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Here it is
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A test detection of Pioneer 10
ButCongress killed NASAs SETI project
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First Intentional Transmission
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The signal digital
Lets look at why digital
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Digital advantage sketch
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Graphical
The message consists of 1679 bits, arranged into
73 lines of 23 characters per line (these are
both prime numbers, and may help the aliens
decode the message). It consists, among other
things, of the Arecibo telescope, our solar
system, DNA, a stick figure of a human, and some
of the biochemicals of earthly life. For less
than 3 minutes it was the brightest source in the
MWG at that frequency.
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Target M13 (30,000 ly)
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Unintentional Transmissions broadcast TV
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Pioneer 10 11 Plaques (1972-3)
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Voyager Record Best of Earth
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Images and Sounds

• Best of Earth
• Narrated by Kurt Waldheim, then U.N. Secretary
  General and now (embarrassingly..) friend of
  fellow Austrian Aaaaanold.

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NASA Take the Search to Space
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SETI_at_home
Windows gt 2000 beware
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Parasitic observations at Aricebo Telescope
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Allen Array

• 350 6.1-m dishes
• 1 10GHz (the water hole)
• Artist concept
• Funded by Microsoft co-founder Paul Allen (and
  COB, Charter Communications)
• Newer, offset Gregorian design

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SETI Inspired Carl Sagans Contact
Ellie Arroway (Jodi Foster) loosely based on
(real) Jill Tarter, former head of NASA SETI
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Fermi Where is everybody?
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Would not be complete without mention