Transcript File

Our Solar System
Characteristics of the moon
Spherical; made of rock
Has no atmosphere, no water,
and no living things
Drastic temperature changes
Earth’s natural satellite
Moon and its effects
One- fourth of the Earth’s diameter
revolves around the earth every
29 1/2 days
the gravity of the moon controls the
tides (trans.)
Types of tides (show trans.)
Spring tides - gravity of
the sun and moon work
together (tide is high)
Neap tides- gravity of
the sun and moon PULL
against each other (tide
is low)
Phases of the moonNew moon
Full moon
show trans.
New moon
Eclipses –
show overhead
Solar eclipse- Sunlight is
blocked by the moon
Lunar eclipse- Earth is
between the sun and moon
moon is visible because of
reflected sunlight
Characteristics of the sun
Made of plasma (high
energy form of matter)
Produces energy as a
result of nuclear fusion
Core temperature
(15,000,000 ºC)
Sun Cont….
kilometers from
Makes up 99% of
the mass of the solar
Formation of the Solar
Formed 5 billion years ago
Formed from a dust cloud of
H+ and He ions. Gravitational
attraction brought these
particles close together
Cloud rotated and formed
shape of a rotating disk known
as solar nebula
Formation of the Sun
The dense concentration at
the centre of the solar nebula
became the Sun
Temp and Pressure increased
as gasses and dust shrunk,
Nuclear fusion reactions began
Formation of Planets
The disk surrounding the sun
became the solar system’s
planets and other objects.
Temperature varied within
Heavier elements condensed
in hotter regions
Ideas from the Past
Copernicus vs. Kepler
 developed idea that Sun was
the centre of the solar system.
In his model the inner planets
move faster in their orbits then
the outer planets.
Further developed the heliocentric
Demonstrated that each planet
orbits the Sun in a shape called an
ellipse (not a circle).
A planet in an elliptical orbit is not
at a constant distance from the
Perihelion: When a planet is
closest to the sun
Aphelion: When a planet is farthest
Two main categories according
to their basic properties:
 Terrestrial planets
 Gas planets
Terrestrial Planets
 are close to the size of Earth
Solid, rocky surfaces
Mercury, Venus, Earth and
Gas Giant Planets
Large, more gaseous and lack
solid surfaces
Jupiter, Saturn, Uranus, and
PLUTO: has a solid surface,
but doesn’t fit into either
category (Discussing Pluto
Remembering the Order
Make up a mnemonic for
memorizing the order of the
planets starting with the
closest to the sun. Include
Pluto in your list.
Ex. My Very Educated Mother
Just Served Us Nine Pizza’s
(Activity to see the distances
between the planets)
 Use the outline to make your own notes for
the 8 Planets + Pluto.
Pluto Debate
There has been an ongoing
debate within the astronomy
world. Should Pluto be labeled
as a planet?
Debate Topics:
Made of rock, but low density
Strange Orbit and Extreme Tilt Maybe Pluto was once a moon of
Neptune, but collided with Triton
(Neptune’s largest moon)
Eccentric Orbit and Tilted Axis Maybe Pluto is related to a comet
Sometimes Pluto is closer to the
Sun than Neptune.
Pluto Debate Activity
Is Pluto a Planet?
Come up with your own definition
of a planet based on the scientific
criteria found in the Celestial
bodies data sheet handout.
Planet Categorization Assignment
is an individual marked assignment
based on the rubric handout. Give
yourself a mark out of 20.
Asteroids and Comets
Small rocky bodies that orbit the Sun
between the planets
Thought to be leftover planetesimals
that didn’t become planets when the
solar system formed.
Most are located in a belt between
the orbits of Mars and Jupiter.
Asteroids Cont.
Meteroid: A fragment of rocky
material that enters Earth’s atm.
Ex. Asteroids collide and break into
Meteor: A streak of light produced
from a meteoroid falling towards
Earth’s surface and burning up in
Earth’s atm.
Meteorite: When a meteoroid
collides with the ground.
Are also remnants from the
formation of the solar system
Comets: Are small, icy bodies that
have a highly elongated orbit
around the Sun.
Hale-Bopp (1997) - When a comet
is with in 3AU (just in between
Mars and Jupiter) it begins to
evaporate and forms a head and
one or more tails.