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Human Evolution

A very brief summary of the evolution of large-brained, bipedal humans.

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Where is Everyone?

Where is Everyone?

Credit: NASA/Ames/JPL-Caltech
Source: en.wikipedia.org/wiki/File:Kepler-22b_System_Diagram.jpg
License: CC BY-NC 3.0

At some point, almost everyone looks up into the night sky and wonders if we are alone in the universe. Scientists have discovered lots of exoplanets in the habitable zones of stars, yet there are no signs of life out there. Where is everyone?

Why It Matters

Credit: NASA/Ames/JPL-Caltech
Source: http://commons.wikimedia.org/wiki/File:Kepler-22b,_Kepler-69c,_Kepler-62e,_Kepler-62f_and_Earth.jpg
License: CC BY-NC 3.0

Kepter-22b is the largest of the habitable-zone planets [Figure2]

  • Kepler-22b is an Earth-like planet, in the habitable zone of a sun-like star about 600 light years from us.
  • There are hundreds, thousands or even millions of other planets with the right conditions to harbor life out there.
  • Technology can advance dramatically.

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With the link below, learn more about alien intelligent life. Then answer the following questions.

  1. If there is intelligent life out there, what should we see in the galaxy? What do we see?
  2. Since we don’t see signs of intelligent life: What are the four possibilities if such life has evolved elsewhere and still exists?
  3. What does it mean to say that civilization carries the seeds of its own destruction? What evidence is there for this idea?
  4. What are scientists doing now to better our understanding of what extraterrestrial life might be like?
  5. What pulls science forward?

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Image Attributions

  1. [1]^ Credit: NASA/Ames/JPL-Caltech; Source: en.wikipedia.org/wiki/File:Kepler-22b_System_Diagram.jpg; License: CC BY-NC 3.0
  2. [2]^ Credit: NASA/Ames/JPL-Caltech; Source: http://commons.wikimedia.org/wiki/File:Kepler-22b,_Kepler-69c,_Kepler-62e,_Kepler-62f_and_Earth.jpg; License: CC BY-NC 3.0

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