ESS 101 EXAM 1 QUESTIONS WITH
VERIFIED ANSWERS
nebular hypothesis - CORRECT ANSWERS ✔✔1. supernova
and formation of primordial dust cloud
2. condensation of primordial dust forms disk shaped
nebular cloud rotating counter-clockwise.
3. proto sun and planets begin to form
4. accretion of planetesimals and differentiation of
planets and moons (4-6 billion years ago).
5. existing solar system takes shape.
Evidence of nebular hypotheses - CORRECT ANSWERS
✔✔1. Planets and moons revolve in a counter-clockwise
direction (not random)
2. almost all planets and moons rotate on their axis in a
counter-clockwise direction.
3. planetary orbits are aligned along the suns equatorial
plane (not randomly organized)
4. observations from Hubble telescope and radio
astronomy indicate that other planetary systems are
forming from condensed nebular dust.
,Terrestrial Planets - CORRECT ANSWERS ✔✔Close to the
sun, dense, small/rocky, silicate minerals, metallic cores
Twelve earths would fit across the diameter of Jupiter.
Jovian Planets - CORRECT ANSWERS ✔✔Far from the sun,
low density, large, gaseous (hydrogen, methane)
Why does the earth and terrestrial planets have so little
molecular hydrogen comprising their respective
atmosphere, yet the primordial dust cloud was mostly
comprised of hydrogen gas? - CORRECT ANSWERS
✔✔Hydrogen gas and helium gas escapes to space when
put in our atmosphere.
Jupiter, saturn, and neptune maintain molecular hydrogen
gas in the atmosphere because they have high density.
Differentiated Earth - CORRECT ANSWERS ✔✔1. Iron Nickel
Core (outer core liquid)
(inner core solid)
2. Fe-Mg silicate mantle
3. Fe-Mg-Al Silicate Crust (Ocean and Continental)
4. Oceans
5. atmosphere
,How is the earth compositionally zoned? - CORRECT
ANSWERS ✔✔Along a density gradient
How did the earth become compositionally zoned? -
CORRECT ANSWERS ✔✔1. Accretion of planetesimals
2. initial heating due to kinetic energy of colliding
planetesimals and compressional heating.
3. additional heating from radioactive decay.
4. iron catastrophe: melting temp of iron reached and
dense iron nickel sink to core and lighter materials are
displaced outwards (including silicate rock of mantle and
crust, ocean waters and atmospheric gases)
5. earth becomes compositionally zoned based on density
(densest iron nickel in core-least dense materials
comprise the atmosphere) 500 mil yrs after the initial
accretion process.
6. convective overturn in asthenosphere, mantle and
outer core still occur today.
Why did the earth heat up and then rapidly cool during
the differentiation process? - CORRECT ANSWERS ✔✔When
earth was solid-heat gain was greater than the heat lost
to space. This means that the internal temperature rises
until it exceeded the melting temp of oxygen and
, nitrogen until exceeded iron nickel catastrophe. Earth is
completely molten and then compositionally zoned.
When earth was liquid- convection-hot gas rises , after it
became molten, the earth rapidly cooled off and
solidified.
Why does earth possess little evidence of its early
accretion history? - CORRECT ANSWERS ✔✔Because of
weathering, plate tectonics, moon has no atmosphere
and biosphere.
Emissions from degassing of the earth during its
differentiation. - CORRECT ANSWERS ✔✔h2o, co2, h2, he,
n2
Where did molecular H and He escape to? - CORRECT
ANSWERS ✔✔space
When did oxygenation of the atmosphere occur? -
CORRECT ANSWERS ✔✔later following evolution of marine
algae and plants that use photosynthesis to convert co2
to o2 as a part of their life processes.
What layers of the earth can be directly observed? -
CORRECT ANSWERS ✔✔crust and uppermost mantle.
VERIFIED ANSWERS
nebular hypothesis - CORRECT ANSWERS ✔✔1. supernova
and formation of primordial dust cloud
2. condensation of primordial dust forms disk shaped
nebular cloud rotating counter-clockwise.
3. proto sun and planets begin to form
4. accretion of planetesimals and differentiation of
planets and moons (4-6 billion years ago).
5. existing solar system takes shape.
Evidence of nebular hypotheses - CORRECT ANSWERS
✔✔1. Planets and moons revolve in a counter-clockwise
direction (not random)
2. almost all planets and moons rotate on their axis in a
counter-clockwise direction.
3. planetary orbits are aligned along the suns equatorial
plane (not randomly organized)
4. observations from Hubble telescope and radio
astronomy indicate that other planetary systems are
forming from condensed nebular dust.
,Terrestrial Planets - CORRECT ANSWERS ✔✔Close to the
sun, dense, small/rocky, silicate minerals, metallic cores
Twelve earths would fit across the diameter of Jupiter.
Jovian Planets - CORRECT ANSWERS ✔✔Far from the sun,
low density, large, gaseous (hydrogen, methane)
Why does the earth and terrestrial planets have so little
molecular hydrogen comprising their respective
atmosphere, yet the primordial dust cloud was mostly
comprised of hydrogen gas? - CORRECT ANSWERS
✔✔Hydrogen gas and helium gas escapes to space when
put in our atmosphere.
Jupiter, saturn, and neptune maintain molecular hydrogen
gas in the atmosphere because they have high density.
Differentiated Earth - CORRECT ANSWERS ✔✔1. Iron Nickel
Core (outer core liquid)
(inner core solid)
2. Fe-Mg silicate mantle
3. Fe-Mg-Al Silicate Crust (Ocean and Continental)
4. Oceans
5. atmosphere
,How is the earth compositionally zoned? - CORRECT
ANSWERS ✔✔Along a density gradient
How did the earth become compositionally zoned? -
CORRECT ANSWERS ✔✔1. Accretion of planetesimals
2. initial heating due to kinetic energy of colliding
planetesimals and compressional heating.
3. additional heating from radioactive decay.
4. iron catastrophe: melting temp of iron reached and
dense iron nickel sink to core and lighter materials are
displaced outwards (including silicate rock of mantle and
crust, ocean waters and atmospheric gases)
5. earth becomes compositionally zoned based on density
(densest iron nickel in core-least dense materials
comprise the atmosphere) 500 mil yrs after the initial
accretion process.
6. convective overturn in asthenosphere, mantle and
outer core still occur today.
Why did the earth heat up and then rapidly cool during
the differentiation process? - CORRECT ANSWERS ✔✔When
earth was solid-heat gain was greater than the heat lost
to space. This means that the internal temperature rises
until it exceeded the melting temp of oxygen and
, nitrogen until exceeded iron nickel catastrophe. Earth is
completely molten and then compositionally zoned.
When earth was liquid- convection-hot gas rises , after it
became molten, the earth rapidly cooled off and
solidified.
Why does earth possess little evidence of its early
accretion history? - CORRECT ANSWERS ✔✔Because of
weathering, plate tectonics, moon has no atmosphere
and biosphere.
Emissions from degassing of the earth during its
differentiation. - CORRECT ANSWERS ✔✔h2o, co2, h2, he,
n2
Where did molecular H and He escape to? - CORRECT
ANSWERS ✔✔space
When did oxygenation of the atmosphere occur? -
CORRECT ANSWERS ✔✔later following evolution of marine
algae and plants that use photosynthesis to convert co2
to o2 as a part of their life processes.
What layers of the earth can be directly observed? -
CORRECT ANSWERS ✔✔crust and uppermost mantle.
