Ancient Astronomers

A philosopher that proved the Earth is a sphere & thought it was at the center of the universe.

• William Herschel
• Isaac Newton
• Aristotle
• Nicolaus Copernicus

He defined the brightnesses of stars (made a scale) & discovered the wobble of the Earth's axis

• Claudius Ptolemy
• Hipparchus
• Tycho Brahe
• Giovanni Cassini

His model of the Earth-centered universe was the cornerstone of astronomy for 1,500 years

• Claudius Ptolemy
• Nicolaus Copernicus
• Charles Messier
• Galileo Galilei

Began a new era of astronomy when he concluded that the Sun was the center of the universe

• Aristotle
• Isaac Newton
• Claudius Ptolemy
• Nicolaus Copernicus

Built an observatory and made the most accurate astronomical observations for more than 20 yrs.

• Giovanni Cassini
• Tycho Brahe
• Hipparchus
• Isaac Newton

Built a telescope and made discoveries which changed astronomy; discovered 4 moons of Jupiter

• Galileo Galilei
• Aristotle
• William Herschel
• Claudius Ptolemy

He discovered the division in the rings of Saturn and found four moons orbiting Saturn.

• Nicolaus Copernicus
• Tycho Brahe
• Giovanni Cassini
• Charles Messier

He showed the laws governing astronomical bodies were the same laws governing motion on Earth

• Isaac Newton
• Charles Messier
• Tycho Brahe
• Hipparchus

He published a list of 110 astronomical objects such as galaxies, nebulae, and star clusters

• Claudius Ptolemy
• Nicolaus Copernicus
• Isaac Newton
• Charles Messier

Discovered Uranus and two of its moons and two more moons of Saturn

• Giovanni Cassini
• Tycho Brahe
• William Herschel
• Aristotle