Lesson Worksheet: History of Astronomy Science

In this worksheet, we will practice recognizing the way our understanding of the solar system has changed over time.


Before the 15th century, people did not believe that the Sun was the center of our universe.

What did they think was the center of the universe?

  • AThe Moon
  • BJupiter
  • CEarth
  • DThe Sun


Astronomy is a branch of science. What does astronomy mean?

  • AThe study of stars, planets, and space
  • BThe study of aliens
  • CThe study of plants
  • DThe study of constellations (stars)


Which scientist developed the theory that the Sun is the center of our universe?

Torun Monument of Nicolaus Copernicus-72 ppi
  • ACopernicus
  • BKepler
  • CGalileo
  • DIsaac Newton


Ptolemy was an astronomer born in Alexandria, Egypt, in the first century AD.

What was his contribution to the field of astronomy?

Ptolemy-72 ppi
  • AHe discovered Mars.
  • BHe discovered that Earth revolves around the Sun.
  • CHe discovered the law of gravity.
  • DHe discovered a mathematical theory on the movements of the Sun, Moon, and planets.
  • EHe discovered how Earth began.


Galileo Galilei was an Italian scientist whose work significantly helped develop our understanding of the solar system.

Galileo Galilei portrait-72 ppi

What did Galileo develop to help astronomers in their studies?

  • AElectricity
  • BA telescope that could be used to observe the planets
  • CThe first space rocket
  • DThe compass

Galileo made important discoveries about the Moon. What did he discover?

  • AThere are craters and mountains on the moon.
  • BEarth orbits the Moon.
  • CThe Moon orbits Earth.
  • DThe Moon creates its own light.


This Greek scientist, who lived from about 90 to 168 AD, proposed a model of the solar system that had Earth at the center. What is his name?

  • APtolemy
  • BAlhazen
  • CCopernicus


In Ancient Greece, the scientist Ptolemy developed an idea about the solar system.

Over a thousand years later, the scientist Copernicus developed a different idea.

Who had a geocentric view of the solar system?

  • APtolemy
  • BCopernicus

Whose view do scientists today agree with?

  • APtolemy’s
  • BCopernicus’s


Galileo Galilei observed the skies in detail to help explain the heliocentric model of the solar system. What instrument did he develop to make his observations?

  • AA microscope
  • BGlasses
  • CA telescope


Copernicus believed that Earth and other planets orbit the Sun. This is a statue of the scientist who used his observations through a telescope to provide evidence for Copernicus’s idea.

Galileo Galilei

Fill in the blank: This is a statue of .

  • APtolemy
  • BAlhazen
  • CGalileo


Alhazen was a Muslim scientist who lived in Egypt in about 1038 AD.

Complete the sentence: Alhazen was the first scientist to .

  • Asuggest the Sun is at the center of the solar system
  • Bpropose a model with Earth at the center of the solar system
  • Cuse math to describe the motion of the planets

This lesson includes 7 additional questions for subscribers.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.