The illusion of a stationary Earth
The sun takes center stage
The math of a year
Solving the calendar puzzle
YOUR GOAL
Master of How we found our place in space
futura Earth Orbits the Sun
We thought the Earth was standing still, But it's our journey 'round the Sun, a cosmic thrill! Every orbit marks a year, a rhythm spun, That's how our calendars have all begun!
futura Ancient Greek astronomer Aristarchus of Samos proposed the first known heliocentric model of the solar system.
futura Claudius Ptolemy designed a highly complex geocentric model that ruled astronomical thought for over 1,400 years.
Aristarchus's giant Sun: Realizing the Sun was much larger than Earth in 270 BCE led Aristarchus to suggest Earth must orbit it.
An astronomical model that places the Earth at the center of the universe. Ancient Greek philosopher Aristotle championed this view, arguing that a moving planet would cause constant, powerful winds.
Which ancient Greek astronomer in 270 BCE proposed the first known model placing the Sun at the center of the solar system?
Which classical Indian astronomer in 1150 CE described a force of attraction that keeps celestial bodies in their orbits?
Why did Claudius Ptolemy introduce epicycles into his geocentric model of the solar system?
Which ancient astronomer wrote the Almagest in 150 CE, cementing the Earth-centered model of the universe for centuries?