Geocentric
Who supported the geocentric model?
Aristotle, Ptolemy and Aryabhata
Who first proposed the heliocentric model?
Copernicus
What did Jupiter’s moons show?
Not everything orbits earth
What is an orbit?
A path planets take around the sun
Why did the geocentric model last for so long?
1.Cultural/Religious beliefs; matched what people saw
What is at the centre of the geocentric model?
Earth
What is at the centre of the heliocentric model?
Sun
What motion sometimes appears backward in the sky?
Retrograde motion
What is rotation?
An object spinning on its axis
Why is technology important in science?
Provides better data/evidence
What did Ptolemy add to explain retrograde motion?
Epicycles
What tool did Galileo use to gather evidence?
Telescope
What keeps planets in orbit according to Newton?
Gravity
What causes day and night?
Earth's Rotation
How did Galileo support the heliocentric model?
Observed Venus’ phases; observed Jupiter’s moons, created telescope
Why did people think Earth wasn’t moving?
They couldn’t feel movement
What planet’s phases supported heliocentrism?
Venus
What modern tool confirmed heliocentrism?
Telescopes and space missions
What is a scientific model?
A representation used to explain an idea or system
Why is the heliocentric model accepted today?
Matches all evidence/observations
Name one reason people believed the geocentric model
Sun and Stars appeared to move; objects fall straight down
Who discovered elliptical orbits?
Johannes Kepler
Why did geocentrism require epicycles?
To explain retrograde motion
What is retrograde motion?
When a planet appears to move backwards in sky
What might people still believe if telescopes were never invented?
Many would likely still believe geocentric model