honors 228 astrobiology w/ dr. h. geller meeting #2 physical origins
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Honors 228 Astrobiology w/ Dr. H. Geller Meeting #2 Physical Origins. Presented 27 January 2011. The Phase Diagram. iClicker Question. What is the name of the phase change from liquid to gas? AVaporization BCondensation CDeposition DSublimation ENone of the above. iClicker Question. - PowerPoint PPT PresentationTRANSCRIPT
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Honors 228 Astrobiologyw/ Dr. H. GellerMeeting #2
Physical Origins
Presented27 January 2011
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The Phase Diagram
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iClicker Question• What is the name of the phase
change from liquid to gas?– A Vaporization– B Condensation– C Deposition– D Sublimation– E None of the above
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iClicker Question• What is the name of the phase
change from solid to gas?– A Vaporization– B Condensation– C Deposition– D Sublimation– E None of the above
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iClicker Question• What is the name of the phase
change from gas to liquid?– A Vaporization– B Condensation– C Deposition– D Sublimation– E None of the above
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iClicker Question• What is the name of the phase
change from gas to solid?– A Vaporization– B Condensation– C Deposition– D Sublimation– E None of the above
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iClicker Question• What is the name of the phase
change from liquid to solid?– A Vaporization– B Condensation– C Deposition– D Sublimation– E None of the above
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Recall Unique Properties of Water
Density vs. Temperature
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iClicker Question• The density of liquid water is
greater than the density of solid water (ice).– A True– B False
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iClicker Question• There is always more to an iceberg beneath
the water’s surface than above the water’s surface– A because liquid water is less dense than ice– B because liquid water is more dense than ice– C because ice is more dense than liquid water– D because water and ice are two different
molecules– E This is a false statement because there’s
always more of an iceberg above the surface than beneath the surface
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Overview of Chapter 1• 1.1 The Possibility of Life Beyond Earth
– Some discussion in 1st meeting• What life are scientists searching for?• Is it reasonable to expect life elsewhere in the
universe?• 1.2 The Scientific Context of the Search
– Usefulness of astronomy in search for life– Utility of planetary science in search for life– Earth’s biology and its usefulness for search for life
• 1.3 Places to Search– Where should we search?
• In our solar system• In our galaxy
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iClicker Question• An extrasolar planet (aka exoplanet)
is– A a planet that is larger than our Sun– B a planet that orbits a star other than
our Sun– C a planet located in another galaxy
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iClicker Question• A habitable planet is
– A a planet that has oceans like the Earth
– B a planet that has life of some kind– C a planet that may or may not have
life, but that has environmental conditions under which it seems that life could arise or survive
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iClicker Question• By a geocentric view of the universe,
we mean– A the idea that Earth resides at the
center of the universe– B the idea that Earth is the only
planet with life in the universe– C a view of the universe shaped by
current understanding of geological science
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iClicker Question• According to current scientific
understanding, life on Earth– A was exceedingly improbable– B arose quite soon after conditions
allowed it– C may have been inevitable, but
took billions of years to arrive
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iClicker Question• The correct order of the eight official
planets in our Solar System, from closest to farthest from the Sun is– A Mercury, Venus, Earth, Mars, Saturn,
Jupiter, Uranus, Neptune, Uranus– B Mercury, Venus, Earth, Mars, Jupiter,
Uranus, Saturn, Neptune– C Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune
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iClicker Question• Today, the research known as SETI
is conducted primarily by– A scanning the skies for signals
from alien civilizations– B sending spacecraft to the
planets– C using telescope to observe
extrasolar planets
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iClicker Question• If we sent one of our current
spacecraft to a nearby star (besides the Sun), the trip would take about– A 10 years– B 100 years– C 1000 years– D 10,000 years– D 100,000 years
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iClicker Question• Scientists today are interested in
searching for life on Mars because– A we see clear evidence of a past
civilization on Mars.– B Mars contains frozen water ice at
its polar caps.– C evidence suggests that Mars had
liquid water on its surface in the distant past.
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iClicker Question• Based on current evidence, the
object in our Solar System most likely to have a deep, subsurface ocean of liquid water is– A Mars– B Titan– C Venus– D Europa– E Io
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iClicker Question• Based on the way scientists view the study of
astrobiology, failure to find life on any other world would mean– A the whole subject has been a waste of time.– B we must have done something wrong, since
life has to exist beyond Earth– C we have learned important lessons about
the conditions that made life on Earth possible
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Overview of Chapter 1• 1.4 The New Science of Astrobiology
– New, are you kidding?• Bio-astronomy, exobiology• Even Galileo and Kepler considered where else in
our solar system we might find life• IAU conference on bioastronomy in 1959!
– Astrobiology according to Geller• ODDS
– origins– development– distribution– search
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Some Words onIn-Class Discussion Groups
• Three to four persons in a group• To start
– Determine leader and recorder (writer)• This will alternate each meeting
• Write the answer to discussion questions so that I can be sure you are addressing the question correctly
• Use complete sentences• Answer in terms that address scientific
issues of questions
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Discussion Questions• 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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Discussion Questions• 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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Discussion Questions• Question #3:
– A) Can any forms of life exist in environments with temperatures much greater than 100°C (the boiling point of water) or much less than 0°C (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) Which of the following elements must be present for life to exist. Explain your reasoning for each choice. (consider hydrogen, potassium, zinc, oxygen, calcium, uranium, magnesium, sulfur, carbon, nitrogen, iron, and sodium)
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Discussion Questions• 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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For Next Meeting• Read Chapter 2 in textbook
– In general you should be reading ahead for the upcoming classes