🌍
Chapter 2: Earth Structure file
Journey to the Center of the Earth
2.2 Welcome to the Neighbourhood
Interstellar space = the region between stars Interplanetary space = the region of vacuum
where there is a vacuum (= an absence of matter) between the orbits of planets, here the
where the concentration is less than one atom per concentration of atoms increases to 5,000 -
liter. 100,000 per liter.
📏
→ The atoms that do exist in interstellar space are
either leftovers from the Big Bang or may be cosmic 1 AU (astronomical unit) = the distance
rays, those are atomic nuclei ejected into space from between the Earth and the Sun = 150
supernova explosions. million kilometers
Distance from
Sun
50000 AU The Sun’s gravitational pull starts.
3500 AU The inner edge of the Oort Cloud, consisting of a vast cloud of icy planetestimals.
The outer edge of the heliosphere, (the “edge” of our Solar System) within this region there are mainly
200 AU
solar-wind particles.
The Kuiper Belt, consisting of a cloud of mainly asteroids and some dwarf planets. The inner edge is
30 - 55 AU
Neptune’s orbit
2.5 AU The asteroid belt between Jupiter and Mars. It contains about 10 million objects
Chapter 2: Earth Structure file 1
, Most asteroids lie between the orbit of Mars and
Jupiter. Some asteroids (known as the Trojans
and the Greeks) border Jupiter’s orbit, while the
Hildas lie between the main asteroid belt and
Jupiter.
The Earth has a magnetic field which is a dipole: it
has 2 poles; the north pole and the south pole. A
magnetic field can be visually represented in a As can be seen in the images, the Oort Cloud is incredibly
vast
drawing. Here the arrows go from the north pole to the
south pole and the direction of the lines shows how a
magnetic object would turn.
The magnetic field protects
Geographic
the Earth from (potentially Magnetic poles
poles
life-threatening) particles in
Southern North magnetic
solar winds, the solar wind North pole
polarity pole
distort the shape of the field.
South magnetic
The region within this South pole Northern polarity
pole
magnetic field is called the
magnetosphere.
🧲 Van Allen belts = 3000 - 10500 km from Earth, where the Earths magnetic field starts to
strengthen and traps both cosmic rays and the rest of the solar wind particles that had enough
speed to penetrate the outer field.
→ Electrons that make it past the Van Allen belt
stream along the magnetic field lines and accelerate
closer to the poles. High-speed electrons interact with
atmospheric oxygen and nitrogen atoms, exciting their
electrons (aangeslagen). When these electrons return
to their normal state, they emit light, causing the gas to
glow. This results in the aurorae we see.
Northern hemisphere aurorae = aurora borealis
Southern hemisphere aurorae = aurora australis
Atmosphere = the gaseous cloak that surrounds the Earth. It consists of
air, which is 78% nitrogen, 21% oxygen and 1% other gasses. Air also
contains various amounts of H20, which at lower elevations form clouds.
The density of the atmosphere increases as you come closer to the Earth’s
surface, because of the weight of the overlaying air. The ‘top’ of the
atmosphere can be considered to be at about 600 km away from the surface.
There are so few molecules at that height that they don’t collide and interact
like a gas does.
🌫️ At the Earth’s surface the atmosphere has a density of 0.12 g/L
or 2.7 x 10²² atoms/L . The unit for air pressure = units of force
per unit area. People can’t survive for long at elevations above 5.5
km due to the lack of air pressure ≈ 0.5 bars.
Chapter 2: Earth Structure file 2
Chapter 2: Earth Structure file
Journey to the Center of the Earth
2.2 Welcome to the Neighbourhood
Interstellar space = the region between stars Interplanetary space = the region of vacuum
where there is a vacuum (= an absence of matter) between the orbits of planets, here the
where the concentration is less than one atom per concentration of atoms increases to 5,000 -
liter. 100,000 per liter.
📏
→ The atoms that do exist in interstellar space are
either leftovers from the Big Bang or may be cosmic 1 AU (astronomical unit) = the distance
rays, those are atomic nuclei ejected into space from between the Earth and the Sun = 150
supernova explosions. million kilometers
Distance from
Sun
50000 AU The Sun’s gravitational pull starts.
3500 AU The inner edge of the Oort Cloud, consisting of a vast cloud of icy planetestimals.
The outer edge of the heliosphere, (the “edge” of our Solar System) within this region there are mainly
200 AU
solar-wind particles.
The Kuiper Belt, consisting of a cloud of mainly asteroids and some dwarf planets. The inner edge is
30 - 55 AU
Neptune’s orbit
2.5 AU The asteroid belt between Jupiter and Mars. It contains about 10 million objects
Chapter 2: Earth Structure file 1
, Most asteroids lie between the orbit of Mars and
Jupiter. Some asteroids (known as the Trojans
and the Greeks) border Jupiter’s orbit, while the
Hildas lie between the main asteroid belt and
Jupiter.
The Earth has a magnetic field which is a dipole: it
has 2 poles; the north pole and the south pole. A
magnetic field can be visually represented in a As can be seen in the images, the Oort Cloud is incredibly
vast
drawing. Here the arrows go from the north pole to the
south pole and the direction of the lines shows how a
magnetic object would turn.
The magnetic field protects
Geographic
the Earth from (potentially Magnetic poles
poles
life-threatening) particles in
Southern North magnetic
solar winds, the solar wind North pole
polarity pole
distort the shape of the field.
South magnetic
The region within this South pole Northern polarity
pole
magnetic field is called the
magnetosphere.
🧲 Van Allen belts = 3000 - 10500 km from Earth, where the Earths magnetic field starts to
strengthen and traps both cosmic rays and the rest of the solar wind particles that had enough
speed to penetrate the outer field.
→ Electrons that make it past the Van Allen belt
stream along the magnetic field lines and accelerate
closer to the poles. High-speed electrons interact with
atmospheric oxygen and nitrogen atoms, exciting their
electrons (aangeslagen). When these electrons return
to their normal state, they emit light, causing the gas to
glow. This results in the aurorae we see.
Northern hemisphere aurorae = aurora borealis
Southern hemisphere aurorae = aurora australis
Atmosphere = the gaseous cloak that surrounds the Earth. It consists of
air, which is 78% nitrogen, 21% oxygen and 1% other gasses. Air also
contains various amounts of H20, which at lower elevations form clouds.
The density of the atmosphere increases as you come closer to the Earth’s
surface, because of the weight of the overlaying air. The ‘top’ of the
atmosphere can be considered to be at about 600 km away from the surface.
There are so few molecules at that height that they don’t collide and interact
like a gas does.
🌫️ At the Earth’s surface the atmosphere has a density of 0.12 g/L
or 2.7 x 10²² atoms/L . The unit for air pressure = units of force
per unit area. People can’t survive for long at elevations above 5.5
km due to the lack of air pressure ≈ 0.5 bars.
Chapter 2: Earth Structure file 2
