“Intro to the Solar
System”
• I. How did the solar system form?
• A. First, the sun formed from its nebula.
• 1. Refer to nebular theory and for more details.
• B. All material from the nebula was not drawn into the sun.
• 1. Left over material collided together making larger objects. .
• 2. These objects became the planets.
• 3. Everything else became dwarf planets, moons, comets,
asteroids, & meteoroids.
C. Two Types of Planets Formed.
• 1. One type is called the inner planets. (Terrestrial)
• 2. Inner planets- The solid iron core, close to the
sun, rocky planets. Planets Mercury, Venus, Earth,
and Mars are classified as inner planets.
• 3. The other type is called the outer planets. (Jovian)
• 4. Outer Planets- The light gas planets, furthest away
from the sun. Jupiter, Saturn, Uranus, & Neptune are
classified as outer planets.
• 5. All planets orbit the Sun in an elliptical orbit.
(Ellipse is the shape. Egg)
“The Inner Planets”
A. Mercury- The closest planet to the sun
• 1. Looks like earth’s moon.
• 2. Craters and cliffs are Mercury’s dominant feature.
• 3. smallest.
• 4. No atmosphere.
• 5. Temperatures get as high as 450 degrees Celsius during
the day, and fall to -185 degrees Celsius at night.
• 6. Named after the Roman Messenger God.
• 7. One day = 59 earth days, one year = 88 earth days.
• B. Venus: “Earth’s Sister Planet”
• 1. The hottest planet in the solar system.
• 2. Temperatures stay constant around
480 degrees C. (900 degrees F)
• 3. Its thick CO2 atmosphere causes the high temperatures.
• 4. CO2 in the Venus’ atmosphere causes the “Green House Effect”.
A.) Radiation from the sun enters Venus’
atmosphere and is absorbed by the ground.
B.) The radiation turns into heat or Infrared
radiation.
C.) Heat then tries to escape from the planet.
(CO2 traps all of the heat trying to escape)
D.) The planet keeps getting warmer & warmer.
E.) Almost the same way a green house stays warm.
Venus Continued:
• 5. Venus rotates clockwise.
• 6. Named after the Roman Goddess of Love and Beauty.
• 7. One day = 243 earth days, One year = 225 earth days.
C. Earth: “Our Planet”
• 1. The only planet that can support human life.
• 2. Only planet that has all states of H2O on it.
A.) Solid = Ice
B.) Liquid = Water
C.) Gas = Water Vapor
• 3. Has one moon.
• 4. The only planet with live plate tectonics.
• 5. Larger than three planets and smaller than four
planets.
• 6. One Day = 24 hours, One Year = 365.25 days.
D. Mars: “The Red Planet”
• 1. Mars looks red because its surface soil has iron in it.
• 2. When iron reacts with O2 you get rust.
• 3. The largest volcano in the solar system
• exists on Mars. ( Olympus Mons )
• 4. Named after the Roman God of War.
• 5. Mars has two moons revolving around it.
A.) Phobos - Larger moon.
B.) Deimos - Smaller moon.
• 6. One Day = 24.6 hours, One year = 687 earth days.
“The Outer Planets”
• I. Outer Planets:
• A. Jupiter: “The Largest Planet”
1. Patterns of colorful clouds are Jupiter’s dominant
feature. Lightning storms continually occur. (The
Great Red Spot is the most spectacular.)
2. Under the clouds, scientists think, lies a huge ocean
of liquid hydrogen.
3. Under the ocean there is a core of solid hydrogen.
4. Jupiter has 63 moons.
• 5. The Galilean Moons, the four
largest moons, are named after Galileo.
He discovered them with his first
telescope.
A.) Ganymede:
* The Largest moon in the solar system.
* Larger than Mercury.
B.) Callisto:
* 2nd largest of Jupiter’s moons.
C.) Io:
* Most famous moon of Jupiter
* Active volcanoes cover the surface.
* Red & Yellow sulfur erupts 180 miles high
into Io’s sky.
“Jupiter Continued”
D.) Europa:
* Covered by a thick layer of H2O ice.
* Under the ice may be some liquid water.
* Scientists and science fiction artists have
speculated that if it is true there may be forms
of life in this water!.
• 6. Jupiter is named after the Roman King of the Gods.
• 7. Has a dark narrow ring system.
• 8. One day = 9hours, 51 minutes, One year = 11.9 years.
• B. Saturn: “The Ringed Planet”
1. 2nd largest planet.
2. Has a large ring system going around the planet.
A.) What is a ring?
* They are made of small pieces of ice and rock.
* They are not solid.
B.) How did they form?
* Scientists believe that moons of Saturn may have
wondered to close to it.
* Then Saturn’s gravity pulled
the moon apart.
* Roche Limit - The distance away from the planet a moon
must be before being torn apart.
* All of Saturn’s rings are inside this limit. .
3. Has a very low density. (Would float on water.)
4. Has 56 moons.
5. Titan: Largest moon of Saturn.
(2nd largest IN SOLAR SYSTEM)
A.) larger than Mercury.
B.) Its atmosphere resembles Earth’s. Made mostly
of Nitrogen.
C.) Has very large oceans of liquid methane.
• 6. One day = 10hours & 40 minutes, One year = 29.5 years.
• 7. Named after Jupiter’s Father & The Roman God of
Agriculture.
• C. Uranus: “The Sideways Planet”
1. Uranus was plotted on a star
chart at one time.
2. Made mostly of Helium and Methane. (these
gases give the planet its blue-green color.)
3. Spins on its side. (Possibly struck by another
object and flipped on its side.)
4. Has a very small, dark ring system.
5. Has 27 moons.
6. 3rd largest planet
7. Named after the father of Saturn &
The Earliest Supreme God.
8. One day = 17.2 hours, One year = 84 years.
• D. Neptune: “The Blue Planet”
1. Last of the gas giant planets.
2. Made mostly of Hydrogen, Helium, Methane.
(This gas gives the planet its blue color.)
3. Has a very small, dark ring system.
4. Has 13 moons.
5. Triton is its largest moon.
* Triton has the coldest surface temperature in the
solar system. (-435 degrees F or -260 degrees C.)
* Has active geysers spewing out liquid methane
and H2O Ice.
6. Named after the Roman God of the Sea.
7. 4th largest planet.
8. One day = 16.1 hours, One year = 164 years.
II. Planets, Dwarf Planets, & Small Solar System Bodies:
A. “Planet”- is a celestial body that:
(a) is in orbit around the sun.
(b) has sufficient mass for its self-gravity to shape it into a
nearly round shape.
(c) has cleared the neighborhood around its orbit of all
objects.
(d) There are 8 of these objects recognized.
B. “dwarf planet”- is a celestial body that:
(a) has all the characteristics above except the one below.
(b) Has not cleared the neighborhood around it’s orbit of all
objects
(d) There are 3 of these objects recognized.
* Pluto (God of the Underworld), Eris (Goddess of
Chaos & Discord), & Ceres (Goddess of Plants).
* All Kuiper Belt objects will eventually join this
status.
* Kuiper Belt- a band of icy debris that is in
orbit around the sun, outside of Neptunes orbit.
C. “Small Solar System Bodies”- All other objects except satellites
orbiting the sun.
ORBITAL PLANES
“Comets, Meteoroids, & Asteroids”
• I.. Comets:
1. Comet -Is composed of dust and rock particles mixed with
H2O, Methane and Ammonia.
2. Where do comets come from?
• A.) Oort Cloud -Large collection of comets, that lies in a
cloud, completely surrounding the solar system.
• B.) This cloud orbits the sun beyond the orbit of Pluto.
3. How do comets
break away????
*PULLED OUT
by a planet (Jovian)
*BUMPED OUT
by another in the
OORT CLOUD
• II. Structure of Comets:
1. A comet starts off as a round ball of dust and rock
mixed with frozen water methane ammonia.
A.) This is the comets nucleus.
2. As it travels closer to the sun the water, methane
and ammonia starts to melt.
3. A cloud of gases form around the ball.
A.) This is the comet’s Coma.
4. The sun then pushes the coma
in the opposite direction.
A.) This forms the comet’s tail.
B.) As the tail forms, pieces of
the comet break away and drift
off into space. .
• 5. As the comet is heading away from the sun it will
eventually freeze up into a simple nucleus again.
• 6. After many trips around the sun the comet will
eventually die.
• III. Asteroids, Meteoroids, Meteors, & Meteorites:
• 1. Asteroids - A piece of rock that is similar to the material
that formed our planets.
A.) Most are located between the orbits of
Mars and Jupiter.
B.) This area is called the asteroid belt.
C.) Asteroids range in size from small dust like
particles to large rocks 900-1000 km wide.
D.) Ceres is the largest asteroid ever found.
(940km wide)
• 2. Meteoroids-Small pieces of rock that
travel through space.
A.) Most are found to be pieces of a comet
that broke away during its orbit around
the sun, or the result of an asteroid
collision.
B.) When a meteoroid passes through the path of the
earth’s atmosphere it is then referred to as a meteor.
• 3. Meteor-
A meteoroid that
burns up in the
earth’s atmosphere.
• 4. MeteoriteA meteoroid so large that it does not
burn up the entire way and strikes
earth’s surface.
Impact Crater