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16 Cards in this Set
- Front
- Back
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Proxima Centauri
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4.22 Light years away
The closest star to the sun |
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Radio Astronomy
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The use of radio waves to detect other life in the galaxy
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The Drake Equation
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Predicts the probability that other civilizations exist within the Milky Way
N = Ns × fp × ne × fl × f i × fc × L |
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Ns
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The number of stars within our galaxy
100 billion (1011) stars in the milky way (our galaxy) |
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fp
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The fraction of stars that have planets
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Transit Method
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Whenever a planet moves between the observer on Earth, the brightness of the star dims and then appears again "periodic oscillation"
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Doppler Spectroscopy
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The gravitational pull of a planet pulls on the star, making the star wobble
The effect is greater with big planets |
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Direct Imaging
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The use of telescopes to take a picture of the parent star and the planet
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Extra-Solar Planets
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Planets that have been found out of our own solar system - 518 found
A planet orbiting around a star, other then our own sun |
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n e
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The number of planets that can potentially support life
Must be in the habitable zone Must look at how far the planet is from the star |
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Properties of Water
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Cohesion - attraction and sticking together
High heat capacity High heat of vaporization Hydration shells minimize Dissolves hydration shells |
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Project Pheonix
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Liquid water on Mars at one point
A machine scraped away dirt on Marks and revealed white stuff The white stuff is crystals from two different times, which suggests sublimation (gas - solid without going to liquid) |
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Fl
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The fraction of planetary systems that can actually develop life
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Fi & Fc
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The proportion of planets with intellegent, communicating life
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L
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The lifetime of a civilzation
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The Fermi Paradox
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So many aliens... Where are they?
1) We cant detect them 2) No other civilizations exist |
