Capter 10: Planet Formation, Cores to Atmospheres Flashcards
part 1
What are the terrestrial planets in our solar system?
Mercury, Venus, Earth, Mars
What are the Jovian planets in our solar system?
Jupiter, Saturn, Uranus, Neptune
What separates the terrestrial and Jovian planets?
The asteroid belt
What is the Kuiper Belt composed of?
Icy bodies and comets beyond Neptune
What is the Oort Cloud?
A distant spherical cloud of comets surrounding the solar system
What is Mercury’s atmosphere composed of?
Mercury has no atmosphere
What dominates Venus’s atmosphere?
Carbon dioxide (CO₂) and nitrogen (N₂)
What is unique about Earth’s atmosphere?
It is composed of molecular nitrogen (N₂) and oxygen (O₂)
What are the primary gases in Mars’s atmosphere?
Carbon dioxide (CO₂) and nitrogen (N₂)
Which planet has the highest density among the terrestrial planets?
Earth
What gases dominate the atmospheres of Jovian planets?
Hydrogen (H₂) and helium (He)
Which Jovian planet has the largest mass?
Jupiter
How is helium unique in the context of planetary atmospheres?
Helium is chemically inert and does not contribute to planetary core formation
Approximately how old is the solar system?
4.6 billion years
What triggered the collapse of the solar nebula?
Gravitational energy and conservation of angular momentum
What percentage of the solar system’s mass is contained in the Sun?
99.8%
Where is most of the angular momentum in the solar system located?
In the rotation and revolution of the Jovian planets
What process clears excess angular momentum from the Sun’s disk?
Solar winds and magnetic field interactions
What are planetesimals?
Small rocky or icy bodies that coalesced to form planets
At what distance from the Sun does the “snowline” occur?
Approximately 2 AU
What materials dominate terrestrial planet formation?
Heavy elements like iron, nickel, and silicates
What enabled Jovian planets to accrete massive atmospheres?
Their gravitational pull and proximity to the gaseous outer disk
What theory explains Jupiter’s migration during the solar system’s formation?
The Grand Tack Model
How was water delivered to the terrestrial planets?
By icy planetesimals from the outer solar system
What role did Jupiter play in delivering icy planetesimals?
Its migration scattered icy planetesimals toward the terrestrial region
What primary gases formed Earth’s early atmosphere?
Carbon dioxide (CO₂) and water vapor (H₂O)
When did Earth’s oceans begin to form?
Between 4.1 and 3.8 billion years ago
What is the Late Heavy Bombardment?
A period of frequent impacts from asteroids and comets
What did the Late Heavy Bombardment contribute to Earth?
Additional water and volatile elements
Why is Venus unable to retain large oceans like Earth?
Its high atmospheric pressure and proximity to the Sun
What is the average temperature on Mercury?
676°F
What materials dominate the asteroid belt?
Iron, nickel, rock, and some silicates
What percentage of Earth’s mass is nitrogen and oxygen?
A majority of the atmospheric composition
How do comets differ in the Kuiper Belt versus the Oort Cloud?
Kuiper Belt comets have more water and volatile ices
What are Jovian planets?
Gas giants composed mostly of hydrogen and helium, located beyond the asteroid belt.
What is the Kuiper Belt?
A region of icy bodies and dwarf planets beyond Neptune’s orbit.
What is the importance of the Oort Cloud?
It is a reservoir of comets that may influence the inner solar system and provide clues about solar system formation.
Why does Earth have the highest density among the terrestrial planets? What does that mean?
Earth’s core is rich in heavy elements like iron and nickel, making it denser. High density means Earth has more mass per unit volume.
What is the solar nebula?
A massive cloud of gas and dust from which the Sun and planets formed.
What is angular momentum?
A physical property related to an object’s mass, velocity, and distance from a rotation axis, influencing rotational stability.
What is the “snowline”?
The distance from the Sun where temperatures are low enough for volatile compounds, like water, to condense into ice.
What are AUs?
Astronomical Units, a measure of distance in space, where 1 AU equals the average distance between Earth and the Sun (~93 million miles).
What are icy planetesimals from the outer solar system?
Small, icy bodies made of water, carbon dioxide, and other volatiles that contributed to the formation of atmospheres and oceans on terrestrial planets.
When was the Late Heavy Bombardment?
Approximately 4 billion years ago.
How does Venus’s high atmospheric pressure and proximity to the Sun prevent it from having oceans?
High pressure and intense heat cause water to exist only as vapor, preventing the formation of liquid oceans.
stages of solar systme development
