Download Our Solar System - Eastern Wayne High

Our Solar System
EARLY
IDEAS that
are Not true!
SUN, PLANETS,
AND STARS
ORBITED A
STATIONARY
EARTH meaning
“Earth centered”
or “Geocentric.”
Retrograde Motion
Is when a planet does not
move east like it normally
would in relation to Earth
Nicolaus Copernicus
Stated the Sun was
the center of the
Solar System.
Meaning “Suncentered” or
“Heliocentric.”
This model
explained
Retrograde Motion.
Kepler’s First Law
Each planet orbits the
sun in a shape called an
ellipse versus a circle.
Astronomical Unit
1.496 x 108 = 1 astronomical
unit. This is the average
distance between the Sun
and each planet!
Eccentricity
The Shape of a planet’s elliptical
orbit!
Perihelion
When a planet is closest to the
Sun in it’s orbit.
Aphelion
When a planet is farthest
away from the Sun.
Orbital Period
The length of time it takes
for a planet or other body
to travel a complete
elliptical orbit around the
Sun
Kepler’s Second Law
Because a planet moves fastest when close to
the Sun and slowest when far from the Sun,
equal areas are swept out in equal amounts
of time.
Kepler’s third Law
A mathematical problem between the size of a
planet’s ellipse (a) and it’s orbital period (P). He
found that the square of the orbital period (P)
equals the cube of the semimajor axis of the
orbital ellipse (a).
2
P
=
3
a
P is a unit of time measured in Earth years.
a is a unit of length measured in astronomical
units.
In addition to Kepler’s
Ideas,
• Galileo was the first person to use a
telescope to observe the sky!
• He supported Copernicus’s idea of the
heliocentric model.
• He found that 4 moons orbited Jupiter.
Lastly, we have Isaac
Newton!
He developed an understanding
of gravity
Newton’s Findings
Law of Universal
Gravitation
Every pair of bodies in the
universe attract each other
with a force that is
proportional to the product
of their masses and
inversely proportional to
the square of the distance
between them.
Center of Mass
Each planet orbits a point
between it and the Sun
called the Center of Mass.
This is the balance point
between two orbiting
bodies, similar to a pivot
point on a see-saw.
Our Solar System
Our solar system is made up of:
Sun
Eight planets
Their moons
Asteroids
Comets
Inner Planets AKA
Terrestrial Planets
From closest to farthest to
the sun:
Mercury
Venus
Earth
Mars
Mercury
Planet nearest the sun
Second smallest planet
Covered with craters
Has no moons or rings
About size of Earth’s moon
No atmosphere
Sister planet to Earth
Has no moons or rings
Hot, thick atmosphere
Brightest object in sky besides sun and moon
(looks like bright star)
Covered with craters, volcanoes, and
mountains
Has clouds of sulfuric acid.
Earth
Third planet from sun
Only planet known to have life and
liquid water (solid, liquid, and gas).
Atmosphere composed of Nitrogen
(78%), Oxygen (21%), and other
gases (1%).
As you know…. Earth’s
axis is tilted
Earth’s axis is wobbling like a toy top
that wobbles if you give it a small
sideways push while it is spinning.
This wobble in the earth’s rotational
axis is the PRECESSION!!
Mars
Fourth planet from sun
Appears as bright reddish color in the night
sky because of it’s high content of iron in
the soil
Surface features volcanoes and huge dust
storms
Has 2 moons: Phobos and Deimos
Outer Planets AKA Gas
Giant Planets
The outer planets are larger, more
gaseous, and lack solid surfaces:
These are farthest from the Sun.
Jupiter
Saturn
Uranus
Neptune
Jupiter
Largest planet in solar system
5th planet from Sun
Brightest planet in sky
60+ moons, 5 visible from Earth
Giant red spot
Has belts (low, warm, dark-colored
clouds that sink
Has zones (high, cool, light-colored
clouds that rise)
Saturn
6th planet from sun
2nd largest
Beautiful set of rings
composed of ice and rock
31 moons
Largest moon, Titan
Easily visible in the night sky
Uranus
7th planet from sun
Rings are dark, almost black
27 known moons
Uranus sits on its side with
the north and south poles
sticking out the sides.
Neptune
8th planet from sun
7 known moons
Triton largest moon
Great Dark Spot: A Storm!
Our Dwarf Planet,
Pluto
Today, Pluto is called a "dwarf
planet." A dwarf planet orbits the
sun just like other planets, but it is
smaller. A dwarf planet is so small
it cannot clear other objects out of
its path.
Pluto was not really a planet
because of its size and location in
space
Pluto
Orbits very slowly
Cold
Covered in Ice
How did our solar
system form?
Many astronomers HYPOTHESIZE that our solar
system began from interstellar clouds (clouds of gas
and dust).
The interstellar clouds begin to move quickly as it
becomes more dense at it’s center.
It begins to spin faster and faster.
The cloud begins to collapse and fall flat and
becomes a rotating disk with a dense concentration
at it’s center.
Sun and Planet
Formation
The disk of dust and gas that formed the Sun and
planets is knows as the SOLAR NEBULA.
The dense concentration at the center became the
Sun.
Eventually, the condensation of materials into liquid
and solid formed slowly forming planets that were
warmer toward the sun and cooler away from the
sun.
The Growth of Objects
Once the condensation slowed, the tiny
grains of condensed material started to
accumulate and merge together to
form larger bodies called
PLANETESIMALS.
Planetesimals collided and merged and
formed Planets!!
Asteroids
Small bodies
Believed to be left over from
the beginning of the solar
system billions of years ago
100,000 asteroids lie in belt
between Mars and Jupiter
Largest asteroids have been
given names
Pieces of Asteroids
Meteroid: When a piece of an asteroid
falls toward Earth and enters Earth’s
atmosphere.
Meteor: The streak of light from a
meteroid.
Meteroite: When the Meteroid hits the
ground.
Comets
Small icy bodies
Orbit the Sun
Give off gas and dust as
they pass by
Coma: The head of a
comet
Nucleus: The small solid
core