Honors 228 Astrobiology Prof' Geller Meeting

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Honors 228 AstrobiologyProf. GellerMeeting 2 -
Physical Origins

• Presented
• 23 January 2003

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Overview of Chapter 1

• 1.1 Life Elsewhere
• discussed 1st meeting
• 1.2 Worlds Beyond Imagination
• distances between worlds
• distances between stars
• communications between star systems
• 1.3 Stuff of Life
• birth and death of stars and planets
• origin of the chemical elements
• chemistry review
• formation of solar system
• other solar systems

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Another Word about Astrobiology

• 1.5 The new science of astrobiology
• How new is it?
• What is new about it?
• Astrobiology according to Geller
• ODDS
• origins
• development
• distribution
• search

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Group Questions from Last Period

• Question 1
• A) Can life exist in places that never receive
  sunlight?
• If Yes What types of life forms could exist?
• If No Cite the physical reasons why life cannot
  exist without sunlight.
• B) What elements are the most important for the
  existence of life? Explain your reasoning.

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Group Questions from Last Period

• Question 2
• A) Consider the following statement
• "For a life form to exist, liquid water must be
  present in the local environment in at least
  small amounts or for short time periods."
• Do you agree or disagree with this statement.
• If You Agree Explain why liquid water is
  necessary.
• If You Disagree What type of life could exist
  and what would the environment be like?
• B) We know that there are 9 planets orbiting the
  Sun in our solar system. Would you expect there
  to be other planets orbiting other stars outside
  our solar system? Explain why or why not.

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Group Questions from Last Period

• Question 3
• A) Can any forms of life exist in environments
  with temperatures much greater than 100C (the
  boiling point of water) or much less than 0C
  (the freezing point of water)?
• If Yes What types of life forms could exist at
  either of these temperatures? State the form of
  life and the corresponding temperature.
• If No Cite the physical reasons why life cannot
  exist at either of these temperatures.
• B) Circle the elements that must be present for
  life to exist. Explain your reasoning for each
  choice. (listed are hydrogen, potassium, zinc,
  oxygen, calcium, uranium, magnesium, sulfur,
  carbon, nitrogen, iron, and sodium)

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Group Questions from Last Period

• Question 4
• A) Describe an environment on Earth that would
  not allow any form of life to exist. Cite
  specific examples and explain why these
  environments cannot support life.
• B) Do scientists have evidence that indicates
  whether life exists anywhere other than Earth?
  Explain your reasoning.

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Sample Phase Diagram
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Density vs. Temperature (water)
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Homework Assignment

• Compare and contrast the differences and
  similarities between the big bang origin of the
  universe and the formation of the solar system.
• minimum 2 typed pages of thoughtful prose
• consider class discussion, material from book,
  and material from HNRS 227