6th Grade

The Discovery of the Solar System

List your top 3 choices for

planets that you would like to

study on a loose leaf sheet of

paper

Long ago, it was commonly

believed that the world was flat…

It was also believed that the

Sun was not in the center of the Solar System.

What was commonly

believed to be the center of our

Solar System in the past?

The Earth was thought to be the center of the

universe

Geocentric Model

Geocentric Model: stated that the Earth was the center of the Solar System

“Geo” means “Earth”

Has anyone ever had a Geode?

Why was it a common belief that the planets revolved

around the Earth?

When you look at the sky, it feels like the Earth is still and that the sun, moon, and

stars are moving around it.

Before there were space shuttles or

advanced telescopes, it was

difficult to discover how

space was oriented.

Astronomers used their observations

and the knowledge they had to develop

Scientific Theories for how the Solar System

was set up

What is a Scientific Theory?

Scientific Theory: an attempt to explain a pattern observed repeatedly in the natural worldex. We notice that the Sun “rises” and “sets,” so we try to make an educated guess as to WHY that is happening

Scientific Theories are supported by observations and results from many investigations

Important to know that a

Scientific Theory can be proved

wrong

Example of a Scientific TheoryExample: Ancient astronomers believed that the planets revolved around the Earth because they did not have evidence yet to prove that theory wrong

They thought that they had evidence that the Earth was in the center of the solar system. Their “evidence” was that they:

Noticed that the Earth felt still or stationary

Noticed that the position of the Sun and planets kept changing in relation to Earth

Scientific Theory

The Earth-Centered Model or “Geocentric Theory” is an example of a Scientific Theory that was incorrect, but seemed true or valid based on the information that was available to astronomers at the time

Remember that a Scientific Theory is a POSSIBLE EXPLANATION for repeatedly observed patterns in nature.

The Geocentric System

In the Geocentric System, the Earth is at the center of the revolving planets and stars.

Believers in the Geocentric Model

1) ARISTOTLE

2) PTOLEMY

Aristotle Lived in 384 BC – 322 BC

Ancient Greek philosopher, scientist, and was an important figure in politics and theatre

mrsvesseymathematicians.wikispaces.com

AristotleOften known as the “grandfather of science” because he believed in using observations and experiments to discover scientific information.

Aristotle’s view on how our Solar

System workedHe and other ancient Greek astronomers realized that the planets moved

The name “planet” means “wanderer” in Greek

Noticed that stars moved, but stayed in the same position to one another

Believed in the Geocentric model and thought that the other planets revolved around the Earth

PtolemyEgyptian astronomer and mathematician

Lived between AD 90- AD 168

Was able to predict the movements of the planets through geometry

Believed in the Geocentric model –that the Earth was the center of the our Solar System

en.wikipedia.org

Ptolemy’s Geocentric Model

was widely accepted for nearly 1,500

years Scienceblog.com

Ptolemy’s Geocentric Model

3 People to remember for the development of the Heliocentric

Model

What is the Heliocentric

Model?

“Helios” means Sun in Greek

Heliocentric Model: a model where the Sun is considered to be the center of the Solar System and the planets orbit around it

3 people who were important to the development of the

Heliocentric Model

Copernicus

Galileo

Kepler

CopernicusLived from 1473-1543

Polish astronomer

Developed the Heliocentric Model

Copernicus discovered that the planets revolve around the Sun and believed they did this in a circular motion

In the 1500s and early 1600s, most people didn’t believe him and still believed in the Geocentric model

ircamera.as.arizona.edu

HOW did he discover the Heliocentric

Model?

Copernicus discovered the

Heliocentric model by

studying the movements of the

planets. He realized all of the planets had the

same annual movement except

for the Sun.

Heliocentric Model

Heliocentric model

Scienceblog.com

GalileoOriginally believed in the Earth centered model

Used the newly invented telescope to make discoveries that support the Heliocentric Model

Saw 4 of Jupiter’s moons revolving around Jupiter, which proved that not everything revolved around the Earth

en.wikipedia.org

Kepler Lived from 1571-1630

Believed in the Heliocentric Model

He discovered that the orbits of the planets were in the shape of an ellipse, NOT a perfect circle

Discovered that orbits are ellipses by studying the orbit of Mars

What is an ellipse?

Ellipse

Ellipse Circle

Kepler learned that planets orbit

the sun in the shape of an

ellipse

Importance events in space history that YOU

should know about

What was the “Space Race?”

Hint: …What is this?

Sputnik I

What is it, and WHY is it important?

Sputnik

Was the first artificial satellite

What is a satellite?

Satellite

Satellite: any object that revolves around another object in an orbit

Orbit: the movement of an object traveling forward in space while at the same time being pulled toward Earth in a curved path as a result of gravity

What do man-made satellites

do?

Manmade satellites can be used for a

number of things: Communication: satellites transmit radio and television programs to locations around the world

Scientific Data: satellites gather spring growth, sea-surface temperature, reflected sunlight, carbon monoxide concentrations

Weather: satellites constantly monitor the Earth’s global weather patterns

Back to Sputnik

Launched by the Soviet Union in 1957

Orbited the Earth for 57 days before gravity pulled it back into the atmosphere, where it burned up

Scared Americans

Why were Americans scared

of Sputnik?

Americans thought that the Soviet Union was using Sputnik to spy on different parts of the world.

This launched a “Space Race” between the United States and the Soviet Union

The first man in space came from

where?

Soviet Union1961 – Yuri A. Gagarin became the first person in space and he orbited the Earth and returned safely

President John F. Kennedy called for the United States to send humans to the moon and return them safely to

Earth His goal was to was to achieve this by the end of the 1960s.

Did the United States meet John

F. Kennedy’s goal?

Yes! First men on the moon on July 20, 1969 from the United States

Apollo 11

Neil Armstrong, Buzz Aldrin, and Michael Collins

What does NASA stand for?

NASA

National Aeronautics and Space Administration