Scientific Theory: an attempt to explain a pattern observed repeatedly in the natural world ex. 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 Theory Example: 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
Aristotle Often 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 worked He 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
Ptolemy Egyptian 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
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 CopernicusGalileoKepler
Copernicus Lived 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
Galileo Originally 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
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
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