Chapter 5: Is There Intelligent Life On Earth

Question 0

Carl Sagan, Pale Blue Dot, 58

Where does all the Earth’s Oxygen(o2) come from?

Answer 0

Explanations of Earth O2

•Earth’s Air: 1/5 oxygen
Sun’s ultraviolet light breaks H20
into hydrogen(lightest gas
escapes to space) and oxygen

  Sun's visible light and Plant life*
  working in conjunction to break 
  h20

Question 1

Carl Sagan, Pale Blue Dot, 58

How Does Spectrometer verify the inherent validity of Oxygen?

Answer 1

Spectrometer verify and confirm oxygen actually being oxygen by looking in the visible and near-infrared spectrum (shorter wavelengths of radiation) for telltale signatures of chemical composition

Question 2

Carl Sagan, Pale Blue Dot, 58b

How does plants & Sun work together to split H2O?

Answer 2

Pigments strongly absorb visible light that split a water molecule by saving the energy of two photons of light, retaining the H(hydrogen) and excreting O(oxygen)

Question 3

Carl Sagan, Pale Blue Dot, ?

Why is plant pigment green?

Answer 3

• chlorophyll- absorbs blue and red light from sun and responsible why plants are green

Question 4

Carl Sagan, Pale Blue Dot, 59

What does the infrared spectrum indicate on the make up of the Atmosphere?

Answer 4

Makeup of Earth Atmosphere
Ozone= O3
Water Vapor=O2
Carbon Dioxide=CO2
Methane=CH4

Question 5

Carl Sagan, Pale Blue Dot, 59

Why is the Sun yellow?

Answer 5

Sun shines in all lights of color, with a peak in yellow

Question 6

Carl Sagan, Pale Blue Dot, 59b

How do greenhouse gases work and what are some?

Answer 6

Greenhouse Gases
            -absorbs the heat that earth 
              tries to radiate away to
              space at night
             -consisting:
               CO2, CH4, H2O,
               N20,O3, CFC*

Carbon Dioxide(CO2)
Methane (CH4)
CFC(chlorofluorocarbons)

Question 7

Carl Sagan, Pale Blue Dot, ?

What are CFCs?

Answer 7

CFC(chlorofluorocarbons)-
Green house gas
depletes O3(ozone)

Question 8

Carl Sagan, Pale Blue Dot, 61

What are nature sources of radio waves?

Answer 8

Radio wave (radio emissions) Natural Sources:
      •trapped electrons in magnetic
       fields of planets
      •shock waves
      • lightning

Question 9

Carl Sagan, Pale Blue Dot, 61b

What is the ionosphere?

Answer 9

ionosphere
        Electrically charged region 
        above stratosphere that
        reflects and absorbs radio
        waves

Question 10

Carl Sagan, Pale Blue Dot, 67

What are some evidence of Life on a planet?

Answer 10

Some Evidence for Life
           •widespread photosynthetic 
            pigment 
           •gas grossly out of equilibrium 
            w/rest of atmosphere
           •highly geometrized patterns 
            rendered on surface
           •steady constellation of lights
            on night hemisphere 
           •nonastrophysical sources of
            radio emissions 
           •unnatural reworking of the 
            surface