# George William Hill

> American astronomer and mathematician (1838–1914)

**Wikidata**: [Q370136](https://www.wikidata.org/wiki/Q370136)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/George_William_Hill)  
**Source**: https://4ort.xyz/entity/george-william-hill

## Summary
George William Hill was an American astronomer and mathematician who lived from 1838 to 1914. He is best known for his work in celestial mechanics, specifically for the development of the Hill differential equation and the concept of the Hill sphere, which defines the region of gravitational dominance of an astronomical body.

## Biography
- **Born:** March 3, 1838
- **Died:** April 16, 1914
- **Nationality:** United States
- **Education:** Rutgers University
- **Known for:** Hill differential equation, Hill sphere, lunar theory
- **Employer(s):** US Nautical Almanac Office, Columbia University
- **Field(s):** Astronomy, Mathematics
- **Influenced by:** Charles-Eugène Delaunay

## Contributions
George William Hill made significant contributions to the fields of astronomy and mathematics, particularly in the area of celestial mechanics. His notable works include:
*   **Hill Differential Equation:** He developed the second-order linear differential equation featuring a periodic function, which bears his name.
*   **Hill Sphere:** He defined the concept of the Hill sphere, describing the region in which an astronomical body dominates the attraction of satellites.
*   **Lunar Theory:** Hill contributed extensively to the theory of the Moon's orbit, building upon the work of French astronomer Charles-Eugène Delaunay.
*   **Lunar Crater:** A lunar crater named "Hill" is named in his honor.

## FAQs
**What awards did George William Hill receive?**
Hill was recognized with several prestigious awards, including the Copley Medal, the Gold Medal of the Royal Astronomical Society, the Bruce Medal, and the Damoiseau prize.

**What academic societies was George William Hill a member of?**
He was a member of numerous distinguished academies, including the National Academy of Sciences, the American Academy of Arts and Sciences, the Royal Society (London), the Royal Swedish Academy of Sciences, the Royal Academy of Science, Letters and Fine Arts of Belgium, the Norwegian Academy of Science and Letters, the Royal Netherlands Academy of Arts and Sciences, the Accademia Nazionale dei Lincei, and the Royal Society of Edinburgh.

**Where did George William Hill work?**
He was employed by the US Nautical Almanac Office and was also affiliated with Columbia University.

## Why They Matter
George William Hill matters for his pivotal role in advancing celestial mechanics during the 19th and early 20th centuries. His mathematical formulations, particularly the Hill differential equation and the Hill sphere, provided essential tools for understanding the gravitational interactions of celestial bodies, influencing subsequent work in lunar theory and astrodynamics. His membership in nearly every major scientific academy of his time underscores the global recognition of his intellectual contributions.

## Notable For
- **Copley Medal recipient**: Awarded by the Royal Society of London.
- **Bruce Medal recipient**: Awarded for research in astronomy.
- **Gold Medal of the Royal Astronomical Society**: A prestigious award in the field of astronomy.
- **Damoiseau Prize**: Received in 1865.
- **Member of the National Academy of Sciences**: A U.S. honorary society and policy research center.
- **Member of the Royal Society**: An English learned society for science.
- **Member of the American Academy of Arts and Sciences**: A United States honorary society.
- **Hill differential equation**: A fundamental concept in mathematical physics named after him.
- **Hill sphere**: A critical concept in astronomy defining gravitational dominance.
- **Hill lunar crater**: A crater on the Moon named in his honor.

## Body

### Early Life and Education
George William Hill was born on March 3, 1838. He pursued his higher education at Rutgers University in New Jersey, United States. His academic background laid the foundation for his career in mathematics and astronomy.

### Career and Affiliations
Hill's professional career included significant tenures at key institutions. He worked for the **US Nautical Almanac Office**, an agency responsible for producing astronomical and navigational data essential for maritime and celestial navigation. This office operates as part of the United States Naval Observatory and focuses on precise timekeeping and positional astronomy. Additionally, Hill was affiliated with **Columbia University**, a private university in New York City.

### Scientific Contributions and Works
Hill's work primarily focused on celestial mechanics and mathematics. He was heavily influenced by the work of **Charles-Eugène Delaunay**, a French astronomer and mathematician known for his work on lunar theory. Hill expanded upon these foundations, producing notable works such as the **Hill differential equation**, a second-order linear differential equation featuring a periodic function. He also introduced the concept of the **Hill sphere**, which defines the region surrounding an astronomical body where it dominates the attraction of satellites. His contributions to lunar theory were significant, and his work in this area is considered a major advancement in the field.

### Awards and Recognition
Throughout his career, Hill received numerous accolades recognizing his contributions to science. He was awarded the **Copley Medal** by the Royal Society of London, the **Gold Medal of the Royal Astronomical Society**, and the **Bruce Medal** for his research in astronomy. He also received the **Damoiseau prize**. His prestige in the scientific community is further evidenced by his membership in a wide array of international academies, including the **Royal Society**, the **Royal Swedish Academy of Sciences**, the **Royal Academy of Science, Letters and Fine Arts of Belgium**, the **Norwegian Academy of Science and Letters**, the **Royal Netherlands Academy of Arts and Sciences**, the **Accademia Nazionale dei Lincei**, the **Royal Society of Edinburgh**, the **American Academy of Arts and Sciences**, and the **National Academy of Sciences**.

### Legacy
George William Hill passed away on April 16, 1914. His legacy endures through the mathematical concepts that bear his name, the **Hill differential equation** and the **Hill sphere**, which remain fundamental in the study of celestial mechanics. His contributions are also commemorated by the lunar crater **Hill**, named in his honor.

## References

1. Great Soviet Encyclopedia (1969–1978)
2. MacTutor History of Mathematics archive
3. Integrated Authority File
4. Find a Grave
5. [Award winners : Copley Medal. Royal Society](https://docs.google.com/spreadsheets/d/1dsunM9ukGLgaW3HdG9cvJ_QKd7pWjGI0qi_fCb1ROD4/pubhtml?gid=1336391689&single=true)
6. [Source](https://phys-astro.sonoma.edu/brucemedalists/george-hill)
7. Complete List of Royal Society Fellows 1660-2007
8. Virtual International Authority File
9. CiNii Research
10. NNDB
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12. KNAW Past Members
13. Brockhaus Enzyklopädie
14. Proleksis Encyclopedia
15. La France savante
16. Freebase Data Dumps. 2013
17. [Source](https://doi.org/10.1016/0315-0860(81)90052-5)
18. CONOR.SI
19. National Library of Israel Names and Subjects Authority File