This document summarizes the formation of the solar system according to the core accretion model. It explains that the solar system began as a solar nebula that collapsed under gravity to form the sun. Heavier elements near the sun merged to form terrestrial planets, while lighter elements further from the sun formed gas giants. The earliest Earth had a hot molten surface and atmosphere of gases like hydrogen and carbon dioxide. Over time, the Earth cooled and developed layers, water was introduced via asteroids, and a water cycle, plate tectonics, and life emerged.

1. The Formation of the
Solar System
Allison Miller

2. Let’s Review the
Planets
• Mercury
• Venus
• Earth
• Mars
• Jupiter
• Saturn
• Uranus
• Neptune

3. Mercury
• The smallest planet, and closest to
the sun
• Terrestrial planet with a thin
atmosphere
• Temperatures vary from -230
degrees to 800 degrees F
• Images of Mercury appear blue
where mineral deposits are present,
and orange where volcanic rock is
present
• It looks brown and orange to the
human eye

4. Venus
• Venus is a terrestrial planet slightly
smaller than Earth
• Venus rotates very slowly; One day
on Venus lasts 243 Earth days
• Venus also rotates in retrograde,
the opposite direction from Earth
• The atmosphere that would be
toxic to humans, as it is made of
carbon dioxide and nitrogen
• Clouds in Venus’ atmosphere are
made of sulfuric acid

5. Earth
• Terrestrial planet with an
atmosphere
• Has a moon
• Supports life

6. Mars
• A terrestrial planet
• Mars takes much longer to orbit
the Sun, with one Mars year
lasting 687 Earth days
• Mars has two moons
• Has an atmosphere of carbon
dioxide, nitrogen, and argon
• Much of the dust on Mars is
composed of iron; oxidized iron
causes Mars to appear red

7. Jupiter
• Jupiter is a gas giant; it does
not have a solid surface
• It rotates quickly, with a 10
hour day
• Jupiter orbits slowly, with each
year taking 12 Earth years
• Atmosphere is made up of
helium and hydrogen
• Jupiter has over 50 moons

8. Saturn
• Like Jupiter, Saturn has a
helium and hydrogen
atmosphere with over 50
moons
• A Saturn year takes 29 Earth
years
• Saturn is surrounded by a ring
system of ice, water, and rock
particles

9. Uranus
• Uranus is an ice giant
• It is made up of water, ammonia,
and methane surrounding a core
• It also has an atmosphere of
hydrogen, helium, and methane
• It has almost 30 moons
• Uranus spins horizontally
• Uranus orbits the sun in over 80
Earth years

10. Neptune
• Neptune is similar to Uranus in
its makeup and atmosphere
• Neptune has 6 rings and more
than 13 moons
• Neptune’s orbit takes over 160
Earth years; it has only
completed 1 orbit since it was
identified in 1846

11. Dwarf planets
• Objects similar in size to moons
• Orbit the sun
• Are made of rock and ice
• Many have an irregular orbit
• Are located in the Kuiper belt
• Include Pluto, Eris, Ceres,
Haumea, Makemake, and
potentially hundreds of others

12. Core Accretion Model
• Our solar system started as a
solar nebula: a cloud of dust
and gas
• Gravity collapsed the materials
in the center together, to form
our sun

13. Core accretion
• Heavier materials orbiting the
sun clumped together
• They formed terrestrial planets
close to the sun
• The solar wind swept lighter
materials away from the sun
• They formed gas giants further
from the sun

14. Terrestrial Formation
• The rocky core formed first of
the heaviest elements
• Lighter materials came to the
outside and formed the crust
• The magnetic field formed
• The lightest elements formed
the atmosphere

15. Earth’s Layers
• The Earth was initially very
cold
• Pressure and radiation heated
the Earth, and caused a shift in
different materials
• Nickel and iron, the heaviest
materials, shifted to the core
• Hydrogen, the lightest material,
began to form the atmosphere

16. Atmosphere
• There was no ozone layer in
the early atmosphere
• A large amount of ultraviolet
light reacher the Earth’s
surface
• There were many electrical
storms

17. Moons
• Particles that draw together, but orbit a planet
• The Earth’s moon is likely made of pieces of the Earth’s crust
• It is theorized that they came from an asteroid strike

18. Plate Tectonics
• Large pieces of crust move on
top of the Earth’s mantle
• This causes changes in the
crust over time
• The continents shift over time
• The plates can collide, forming
mountains and volcanoes

19. Volcanoes
• Volcanoes allowed gases to
escape from the Earth’s mantle
into the atmosphere
• The earliest atmosphere
contained hydrogen, carbon
dioxide, nitrogen, ammonia,
and methane
• There was little to no oxygen

20. Water
• Water was introduced when
asteroids made of ice hit the
Earth’s surface
• Earth is in a special position,
where water remains in its
liquid state and never
completely freezes or
evaporates

21. Water Cycle
• Water vapor came from
underground
• Massive rainstorms covered
the Earth’s crust
• Water dissolved minerals and
soluble gasses
• The early seas were formed

22. Disk Instability Model
• Focuses more on the formation
of gas giants
• Clumps of gas and dust bind
together
• They compact quickly into
planets that can maintain an
atmosphere