Download A. Comet: dust and rock particles combined with frozen water

The Solar System
Section I
The Solar System
Age of our solar system is 4.6
billion years old.
The solar system is made up of 8
planets since Pluto has been
denoted to and many smaller
objects that orbit the sun.
Ideas about the night sky have
changed over time

Earth-centered model ( Geocentric
theory)– early Greeks thought planets,
Sun, Moon, and stars revolved around
Earth

Sun-Centered model
(Heliocentric)
Nicholas Copernicus and Galileo Galilei
observed that the moon revolved around
Earth and that Earth and other planets
revolved around the Sun
Modern View

solar system includes Sun, eight planets,
many small objects.
NEBULA THEORY (origin of
solar system)

a nebula of gas, ice, and dust slowly
formed in space
A cloud of material in the nebula
slowly rotated in space
As the cloud contracted, it grew warmer,
triggering a nuclear fusion reaction that
created the Sun
Nuclear Fusion happens in the Sun. Nuclear
Fusion is a process that occurs when atoms
combine to form a new element and release
energy.
The leftover matter became the
planets and asteroids
First four inner planets – small and rocky
with iron cores.
 last four outer planets – large and
lightweight …


Planet orbits are elliptical and the Sun is
not directly in the center of the orbits.
Section II
The Inner Planets also known as the
terrestrial planets.
 What is a major reason the inner planets
have smaller levels of Helium and
Hydrogen? Answer: These are lighter
gases so the Sun’s energy burns off the
lighter gases.

Mercury
Closest to the Sun, smallest planet
 Difficult to observe with the naked eye
because it is so close to the sun
 Mercury, Venus,
And Jupiter have
Virtually no axial tilt

Weak magnetic field suggests an iron core
 Has many craters and high cliffs
 no true atmosphere, so surface
temperatures range from very hot to very
cold
 Fastest Planet
 No Moons

Venus
Sometimes called Earth’s twin

second from the Sun and similar to Earth
in size and mass
extremely dense atmosphere of clouds
 Carbon dioxide traps solar energy
 Venus has a very dense atmosphere of
C02
 Hottest planet
 No Moon

The dense atmosphere of CO2 causes an
intense greenhouse effect
 Results in surface temperatures between
450°C and 475°C
 Venus and Uranus rotate clockwise
(backwards or retrograde). Most planets
spin counter-clockwise (direct rotation)

Earth
average distance between Earth and the
Sun is 150 million km/ 93 million miles or 1
Astronomical Unit (AU)
 Water exists on surface as solid, liquid,
and gas which supports life
 Earth also has high amount of oxygen
(21%) in its atmosphere so animal life is
possible
 Earth has 1 moon

More than 70% of surface covered with
water
 Atmosphere protects surface from most
meteors and Sun’s radiation. This is why
the Earth does not experience as many
meteor strikes as the Moon.

Mars
Called red planet because iron oxide in
rocks makes them reddish-yellow
 Polar ice caps made mostly of frozen
carbon dioxide and frozen water
 Atmosphere is very thin
 2 moons


Has largest volcano in the solar system

Soil shows NO evidence of life………..
perhaps……………

Has gullies and deposits of soil and rocks,
which may indicate the presence of liquid
groundwater
Thin atmosphere of mostly carbon dioxide
 Strong winds caused by differences in
temperature between day and night


Mars is tilted on its axis, which causes
seasons
MarsTwo small moons, Phobos
and Deimos
Volcanoes
Only the inner planets have volcanoes
 Venus and Earth are the only ones that
have active volcanoes.
 Mercury and Mars have extinct volcanoes.
 Olympus Mons is found on Mars
 The outer planets are gas giants and do
not have land masses on which to have a
volcano

Where is the asteroid belt located?
Answer-between Mars and Jupiter
What is the asteroid belt?
Answer-rocky objects measuring mm
To Km in diameter
Section III
The Outer Planets also called Gas Giants
 Have high concentrations of hydrogen

Jupiter

fifth planet from the Sun, largest planet in
the solar system
Below atmosphere, liquid hydrogen and
helium are suspected
 Solid rocky core may exist below liquid
level

The Great Red Spot is the most
spectacular of Jupiter’s many
constant high-pressure gas storms
This storm is
Several times
the size of
Earth.
Jupiter
Earth
Jupiter Has rings
Has at least 61 moons – four are
large and have atmospheres
(Io, Europa, Ganymede, and
Callisto)
Io

is very volcanically active; the closest
large moon to Jupiter
Europa

composed mostly of rock; may have an
ocean of water under a thick layer of ice
Ganymede

largest moon in solar system, even larger
than planet Mercury
Callisto

cratered rock and ice crust may surround
a salty ocean and rock core
Saturn

Sixth planet from the sun, second largest
in the solar system, lowest density

Thick outer atmosphere of hydrogen,
helium, ammonia, methane, and water
vapor

Might have a small, rocky core

Each large ring composed of thousands of
ringlets of ice and rock particles
Saturn Has at least 31 moons
Saturn’s Largest moon, Titan, is
larger than the planet Mercury

Thick clouds on Titan prevent scientists
from seeing surface…….
Uranus
Seventh planet from the Sun, large, and
gaseous
 Tilt of Uranus
Angle is 90
degrees

Uranus has thin, dark rings
 Atmosphere of hydrogen, helium, and
methane
 Methane makes the planet bluish-green in
color
 22 moons

Axis of rotation nearly parallel to
plane of orbit
Neptune

eighth planet from the sun, large and
gaseous
bluish-green colored atmosphere similar to
that of Uranus
 Storms on Neptune reveal an active and
rapidly changing atmosphere
 has at least 11 moons, of which pinkish
Triton is largest

Pluto
Pluto is a dwarf planet located within the
Kuiper Belt.
 Pluto is small and nonluminous which is
why powerful telescopes have problems
detecting Pluto.

A. Comet: dust and rock particles
combined with frozen water,
methane, and ammonia.
1. Halley’s comet: orbits Sun
every 76 years.
2. Oort Cloud: large group of
comets surrounding solar system
beyond Pluto.
4. Comet structure: large dirty
snowball of frozen rock and ice.
Comets
a. Ice and dust vaporize as comet nears
Sun.
 b. Vaporized material forms bright cloud
called coma around comet nucleus.
 c. Solar wind pushes on gas and dust in
the coma, causing the particles to form a
tail that always points away from the Sun.
 d. Eventually, most of the ice in the
comet’s nucleus vaporizes, leaving only
small particles.

Comets vaporize and break up
after passing close to the Sun
several times. When the nucleus
breaks up, pieces spread out. The
dust and rock fragments are called
Meteoroids.
B. (1.) Meteoroid: name given to
small pieces of comet when they
move through space.
B. (2.) Meteor: small meteoroid
that burns up in Earth’s
atmosphere.
B. (3.) Meteor Showers: occur when Earth’s
orbit passes through a group of meteoroids
that enter the atmosphere.
B. (4.) Meteorite: meteoroid that
strikes Earth.
C. Asteroid: rock similar to that
which formed planets.
C. (1.) Most asteroids lie in an
asteroid belt located between Mars
and Jupiter.
Asteroid Info:
Jupiter’s gravity may have kept these
asteroids from forming a planet.
 some planets’ moons may be asteroids
pulled from the asteroid belt.
 asteroid sizes range from very tiny to 940
km in diameter.
