Johannes Kepler Facts & Worksheets

Johannes Kepler was a mathematician and astronomer who significantly contributed to planetary motions, logarithms, optics, and many more in science. He also became a professor of mathematics, district mathematician, and calendar maker. His discoveries and findings became fundamental concepts in different areas of science and mathematics.

See the fact file below for more information on Johannes Kepler, or you can download our 26-page Johannes Kepler worksheet pack to utilize within the classroom or home environment.

Key Facts & Information

EARLY LIFE

• Johannes Kepler was born on December 27, 1571, in Weil der Stadt. 
• He was the son of Heinrich Kepler, a mercenary soldier killed when Johannes was five years old, and Katharina Guldenmann, a herbalist who helped run an inn owned by her father.
• Johannes lived with his father in his grandfather’s inn. Heinrich left them to fight in a war when he was five.
• Kepler studied at a local school. Afterward, he moved to the Protestant Seminary of Maulborn, where he intended to be ordained. He then enrolled at the University of Tübingen.
• He studied theology and took courses in Greek, Philosophy, and Hebrew. 
• Although he took these courses, he still stood out in mathematics. He was one of the few students with the intellectual capacity to learn the work of Nicolaus Copernicus.
• Kepler also learned astronomy from Michael Mästlin, one of the leading astronomers of the day. During that time, the curriculum was geometric astronomy, the current version of the Ptolemaic system. In this system, all seven planets–Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn–moved around the earth. During this time, astronomers were content with calculating the positions of the planets and left the physical mechanism to the natural philosophers.
• Kepler did not settle with this principle, and in his earliest published work, he proposed to consider the actual paths of the planets and did not use circles to construct them.
• Kepler also agreed with Copernicus’s heliocentric hypothesis, which states that the Sun lay at the center of the solar system.
• In 1591, he passed the M.A. examination and he continued his studies as a graduate student.
• At 23, Johannes Kepler accepted an appointment as a professor of mathematics and astronomy at the Protestant School in Graz, Austria.
• He taught arithmetic, geometry, Virgil, and rhetoric for six years. 
• He also became a district mathematician and a calendar maker.

RELIGIOUS BELIEFS

• Johannes was a religious man, and his belief influenced his works.
• For him, his work was a fulfillment of his Christian duty. His works contained references to God, and he believed that God made men in His image. Therefore, men are capable of understanding the universe that He created.
• Kepler also believed that God made the universe according to a mathematical plan. This belief was inspired by the works of Plato and Pythagoras.
• While studying and mastering scientific theories, Kepler would always have philosophical beliefs. Kepler believed that God manifests Himself not just in words written in the Scripture but also in the magnificent arrangement of the universe.
• For Kepler, astronomy, if viewed philosophically, is the best path to God.
• Kepler was known as an unorthodox Protestant. He wanted to become a minister, so he attended a protestant seminary.
• Kepler did not become a minister but always referred to the Creator when he discovered many things in the universe. 
• He geometrically represented the Trinity (the Father, the Son, and the Holy Spirit) in a sphere.

PERSONAL LIFE

• Johannes Kepler married twice. On April 27, 1597, Kepler married Barbara Muller. Muller was widowed and had a young daughter named Gemma from his first marriage.
• Johannes and Barbara had two daughters. However, they died in infancy. 
• The couple had three more children. Later, Barbara became seriously ill and eventually died in 1612.
• Following this, their three sons contracted smallpox, and one of his sons, Friedrich, died. 
• Kepler decided to leave Prague and moved to Linz, where he met his second wife, Susanna Reuttinger. On October 30, 1613, they married. 
• Johannes and Susanna had seven children, but five of them died. Three of their seven children died in infancy, the same as during his first marriage. 
• Despite these events, Kepler was still able to publish “Harmony of the Worlds” in 1619 and “Epitome of Copernican Astronomy” between 1618–1621, a book published in three volumes. 
• In 1625, after the Counter-Reformation removal, Catholic authorities temporarily removed his library and ordered his children to attend mass. 
• To add to Kepler’s emotional upheavals, his mother was also one of the women accused of practicing witchcraft and imprisoned for three months. Johannes stayed by her side.
• Before he died, Kepler wrote a story about a trip to the moon called “The Dream,” and it was considered the first science fiction work. 
• Kepler died of fever on November 15, 1630.

SCIENTIFIC CONTRIBUTIONS

• Johannes Kepler published a defense of the Heliocentric Model. It was his first major astronomical contribution. 
• In 1956, Johannes published the “Mysterium Cosmographicum” or “The Cosmographic Mystery.”
• This work tried to justify the six planets, Mercury, Venus, Earth, Mars, Jupiter, and Saturn, and their distance from the Sun based on the five Platonic solids.
• Although there was a flaw in the main thesis of this work, “The Cosmographic Mystery” is still considered an important work in astronomy.
• Kepler also discovered that planets move at different speeds. He used the astronomical and planetary observations of Tycho Brahe, a Danish astronomer, to analyze the orbit of Mars. 
• Kepler discovered that Mars did not move in a perfect circle because, at times, it would move closer to the Sun. As Mars went farther, it moved faster. 
• Kepler concluded that the power radiated by the Sun weakens with distance, causing the planets to move faster or slower as they get closer or further from it.
• This is where Kepler deduced his second law of motion or the Law of Areas.
• Remarkably, Johannes Kepler formulated the second law of planetary motion before he arrived at the first law.
• Kepler attempted to figure out the mathematical shape of Mars’s orbit, so he calculated the planet’s entire orbit. 
• He experienced 40 misses in 1605 until he got it right. 
• In his calculations, Kepler found that Mars follows an elliptical path around the Sun. He thought that astronomers overlooked this because the solution was too simple. 
• Kepler then arrived at his first law of planetary motion or the Law of Orbits. 
• Kepler also contributed to optics as he was the first to correctly explain the working of the human eye.
• Kepler was the first person who used the term camera obscura, a natural optical phenomenon used to describe how light rays reverse themselves when they pass through a small aperture. This results in the inverted image on the screen opposite the opening, just like the pinhole camera works.
• In 1618, he continued his research because he wanted to find out more about the orbits of the planets. 
• He published “Harmonices Mundi” or “The Harmony of the World,” which explains the regular polygons, the congruence of figures, music, astrology, and the motions of the planets. 
• He also came up with the third law of motion or the Law of the Periods, which states that if the time it takes a planet to complete one orbit around the Sun is squared, it is proportional to the planet’s distance from the Sun when cubed.
• As Kepler extended his studies to the human eye, he discovered that the image is reversed by the eye’s lens and is formed in the retina. 
• Because of that, Kepler established the foundation for ophthalmological optics.
• Kepler’s discovery was also used to explain central visual acuity, visual field, dark adaptation, and errors of refraction. 
• Kepler also explained how convex and concave lenses could correct presbyopia (the eyes’ inability to focus on nearby objects) and myopia (the eyes’ ability to see close objects clearly).
• Kepler also developed a telescope after explaining the theoretical basis of double-convex converging lenses and double-concave diverging lenses to produce a Galilean telescope.
• He described the improved refracting telescope, which uses two convex lenses. This eventually became known as the Keplerian telescope. 
• The Keplerian telescope could achieve higher magnifications than the Galilean telescopes.

Johannes Kepler Worksheets

This fantastic bundle includes everything you need to know about Johannes Kepler across 26 in-depth pages. These ready-to-use worksheets are perfect for teaching kids about Johannes Kepler. Johannes Kepler was a mathematician and astronomer who significantly contributed to planetary motions, logarithms, optics, and many more in science.

Complete List of Included Worksheets

Below is a list of all the worksheets included in this document.

1. Johannes Kepler Facts
2. True or False?
3. Kepler’s ID
4. Identification
5. How Well Do You Know?
6. Kepler’s Crowd
7. Keplerian Telescope
8. Planetary Motion
9. Book Cover
10. More Discoveries
11. Immortal Lines

Frequently Asked Questions

Who was Johannes Kepler?

Johannes Kepler was a German astronomer, mathematician, and astrologer who lived from 1571 to 1630. He is best known for his laws of planetary motion, which helped to establish the field of celestial mechanics.

What were Kepler’s three laws of planetary motion?

1. Kepler’s three laws of planetary motion are:

• The orbits of the planets are elliptical, with the sun at one focus of the ellipse.
• A line drawn from a planet to the sun sweeps out equal areas at equal times.
• The square of a planet’s orbital period is proportional to the cube of its semi-major axis.

What was Kepler’s contribution to astronomy?

3. Kepler made many significant contributions to astronomy, including:

• His three laws of planetary motion, which explained the motions of the planets and laid the foundation for the study of celestial mechanics.
• His work on optics included the discovery of the inverse-square law of light intensity and the development of the first telescopes designed for astronomical observation.
• His work on the nature of light and the formation of images helped to establish the field of physical optics.

What was Kepler’s relationship with Tycho Brahe?

Kepler worked with the Danish astronomer Tycho Brahe for several years, analyzing the data that Brahe had collected on the motion of the planets. Kepler used this data to develop his laws of planetary motion, which he published in 1609.

What was Kepler’s personal life like?

Kepler had a difficult personal life, marked by financial struggles, family tragedies, and conflicts with religious authorities. He was a devout Lutheran and believed that his work in astronomy was a way to better understand God’s creation. Kepler had six children, three of whom died in childhood, and his wife was accused of witchcraft and imprisoned for several years. Despite these challenges, Kepler continued to work on his scientific pursuits and made many important contributions to the field of astronomy.

Link/cite this page

If you reference any of the content on this page on your own website, please use the code below to cite this page as the original source.

<a href="https://kidskonnect.com/people/johannes-kepler/">Johannes Kepler Facts & Worksheets: https://kidskonnect.com</a> - KidsKonnect, May 11, 2023

Link will appear as Johannes Kepler Facts & Worksheets: https://kidskonnect.com - KidsKonnect, May 11, 2023