Johann Franz Encke

High school (ages 12+)
Space & Astronomy

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Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/johann-franz-encke

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. When was Johann Franz Encke born?September 23, 1791
2. Where was Johann Franz Encke born?Hamburg, Germany
3. What is the career?Astronomer, Director of the Berlin Observatory (1825-1865)
4. What is Johann Franz Encke known for?He was a German astronomer who calculated the orbit of comet 2P/Encke and measured the Earth‑Sun distance.
5. Why was Encke's calculation of the comet's period important?He found the comet’s period was only about 3.3 years, the shortest known then, and noticed it was getting shorter because of outgassing.

Celestial Mechanics: The branch of astronomy that deals with the motion of celestial bodies under the influence of gravity.
Solar Parallax: The apparent shift in the Sun's position due to Earth's orbit, used to calculate the Earth-Sun distance.
Secular Acceleration: A long-term, gradual change in the speed or period of an orbiting object, often due to non-gravitational forces.