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Searching for Habitable New Worlds and Life in the Universe Hosted by Night Sky Network
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Universal Laws of Biology ? Lawrence Hall of Science Liquid Water DNA Intelligence
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Is there life elsewhere in our Solar System? The Only Known Site of Biology In the Universe.
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Mars Liquid Water Impossible Pressure = 0.01 of Earth... too low for Liquid water.
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Jupiter and Two Moons Io Europa
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Europa Surface of Jupiter’s Moon: : Europa Fractures in Floating Ice Icebergs
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Jupiter’s Moon Europa Jupiter’s Moon: EuropaSub-CrustOcean.. Life in the Ocean?.. Hydrogen-Carbon compounds likely: Amino acids First New Ocean Since Balboa
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Now Exiting our Solar System to … The Milky Way Galaxy.............. Meanwhile, we are hunting for abodes Beyond our Solar System
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The Discovery of Other Collaborators: Paul Butler, Debra Fischer, Steve Vogt Chris Tinney, Greg Laughlin, Hugh Jones Andrew Cumming, Greg Henry, Jack Lissauer Jason Wright, Brad Carter, Eugenio Rivera, Chris McCarthy, John Johnson www.exoplanets.org
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Planet Detection Wobble of Star: Gravitational pull by the planet
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V PL 2 = G M Star / r V PL ~ 10 km/s V Star = V PL V STAR ~ 10 m/s V Star = V PL V STAR ~ 10 m/s x (M PL /M JUP ) x (M PL /M JUP ) Momentum: Wobble Velocity Wobble Velocity M PL M PL M STAR M STAR Energy Equipartition: ( )
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12 years... Jupiter (Meters/sec) Need Telescope...
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World’s most Successful Planet Search 1997 – Present 1997 – Present Survey: 1300 Nearby Stars Keck 1
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Echelle Spectrometer CCD Echelle Grating Collimator Starlight From Telescope High Resolution ``Echelle” Spectrometer
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Spectrum of Star: Doppler Effect Doppler Precision: v / c ~ 10 -9 ~ 10 -9 4096 Pixels
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16 Cygni B Mass = 1.7 M JUP (Min) Orbit Period 2.2 yr Not Sinusoidal VelocityWobble
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Orbit of Planet around 16 Cygni
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16 Cygni: Planet & Moon
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Life on Gas Giant Planets ? Floaters Earth-Like Moon
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Mass = 0.62 M JUP 70 Days
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Upsilon Andromedae : Velocity Residuals
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0.6 M JUP 2 M JUP 4 M Jup Upsilon Andromedae: Triple Planet System Planets have No Names........
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Upsilon Andromedae
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Per = 1.94 d M = 7.5 M Earth Gliese 876 d Lowest Mass Exoplanet : 7.5 Earth-Masses 1.94 Days 5 m/s
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Three Planets Orbiting Gliese 876 7 1/2 Earth-masses
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Ring in Between: Lukewarm Lukewarm Hot: 370 C Cold: -100 C 7.5 Earth-Mass Planet Orbiting Gliese 876 Tides: One Planet Side always Faces Star
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Milky Way Galaxy 200 billion stars ~10% of all Stars ~10% of all Stars have detected planets. have detected planets. Detected so far: Jupiter-mass Saturn-mass Neptune-mass ~ Earth-Mass ?
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More Low-Mass Planets Planet Mass
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Only Known Abode of Life But are they Habitable ? Environments Must Environments Be “Just Right” For Life ? Conclusion: Many Earth- mass Planets
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Yellowstone National Park : Suitable for Life ? Boiling Geysers Boiling Geysers Freezing winter Freezing winter Sulfuric acid. Sulfuric acid. One of the Least Hospitable Places on Earth:
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Yellowstone Pinwheel Geyser BacteriaThrive Near Boiling: T ~ 80 C Water: Acidic as battery acid Each color a different species of bacterium
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Life at High Temperature and High Acidity Temp = 65 C pH = 2 pH = 2 Yellowstone
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Churning Cauldron Yellowstone Churning Cauldron Boiling Temp
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Churning Cauldron Yellowstone Churning Cauldron Boiling Temp, pH = 2 Bacteria & Algae Thrive Algae pH = 2 Corrosion
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Cyanidium Calderium Life at Extreme Temp & Extreme Acidity Lives only at T > 60 C
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Extremophiles Show that Life Tolerates heat or cold Takes food from a variety of sources Thrives in acidic or alkaline environments Copes with Intense Solar Radiation - - or none! Copes with Intense Solar Radiation - - or none! Liquid Water Life Primitive Life: Common in the Universe
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Is our Milky Way Galaxy Teeming with Intelligent Life ? Galaxy is Galaxy is 10 Billion Years Old 10 Billion Years Old - - - Twice the Age of Earth - - - Twice the Age of Earth 50% of Stars are50% of Stars are as Old as the Sun & Earth as Old as the Sun & Earth Many stars & planets older by billions of years! Many stars & planets older by billions of years! How Many Civilizations ?
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Is our Milky Way Teeming with Intelligent Life ? 20 Billion20 Billion Planetary Systems: Planetary Systems: 1/2 are older than Earth 1/2 are older than Earth What fraction have What fraction have Intelligent Life? Intelligent Life? Pessimist: 1 in a MillionPessimist: 1 in a Million There must be Thousands of Civilizations In the Milky Way Galaxy...
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............
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Where is Everybody? Why Didn’t They Come Here? Moon: No Alien Spacecraft, Crash Debris, ObeliskMoon: No Alien Spacecraft, Crash Debris, Obelisk Mars: Same StoryMars: Same Story Earth: Lovely Planet for 4 Billion Years...Earth: Lovely Planet for 4 Billion Years... Yet, no Alien Settlement. Yet, no Alien Settlement. 100’s of Telescopes: No Alien Ships spotted100’s of Telescopes: No Alien Ships spotted Night Sky: No Exotic Rocket ExhaustNight Sky: No Exotic Rocket Exhaust No Robotic Probes Visit Solar SystemNo Robotic Probes Visit Solar System SETI: No Radio Signals in 40 years.SETI: No Radio Signals in 40 years.
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Where Is Everybody? Thousands of Civilizations in GalaxyHypothesis: - Thousands of Civilizations in Galaxy - Head Start of Billions of years. - Head Start of Billions of years. They should be Near! They should be Near! Migration Throughout Galaxy: Easy with robotic spacecraft ================================================= Observation: No Aliens Detected, and no Traces. Hypothesis possibly flawed.Conclusion: Hypothesis possibly flawed. ( Ants eventually find your Kitchen) ( Ants eventually find your Kitchen)
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. How Long do Technological Civilizations Last? Expect: 1000 Civilizations in 5 Billion Years in 5 Billion Years For Multiple Civilizations Today, Lifetimes Must Overlap: Lifetime > 5 Million yr
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Recipe for Exobiology: Planets Chemicals Water Energy - - - Stars, Tidal, Geothermal Stars, Tidal, Geothermal Life: Probably Common in the Universe. Primitive Life, at least February 5, 1996
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SETI ATA: Proposed Radio Telescope Array
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Life in our Milky Way Galaxy: Life in our Milky Way Galaxy: Primitive Life: Common Intelligence: Rare ? Intelligence Semi-Intelligent Life forms..
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www.exoplanets.org
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