# Anders Jonas Ångström

> Swedish physicist

**Wikidata**: [Q187258](https://www.wikidata.org/wiki/Q187258)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Anders_Jonas_Ångström)  
**Source**: https://4ort.xyz/entity/anders-jonas-angstrom

## Summary
Anders Jonas Ångström was a Swedish physicist and astronomer best known for his pioneering work in spectroscopy and the study of light. He is renowned for identifying hydrogen in the Sun's spectrum and for establishing the unit of length named after him, the ångström (0.1 nanometer), which became fundamental in atomic physics and chemistry.

## Biography
- **Born**: August 13, 1814, in Lögdö, Sweden
- **Nationality**: Swedish
- **Education**: Uppsala University (PhD in physics)
- **Known for**: Founding spectroscopy, discovering hydrogen in the Sun, and defining the ångström unit
- **Employer(s)**: Uppsala University (professor), Uppsala Astronomical Observatory (director)
- **Field(s)**: Physics, astronomy, spectroscopy

## Contributions
Anders Jonas Ångström made groundbreaking contributions to spectroscopy, including:
- **Solar Spectrum Analysis (1862)**: Published *Recherches sur le spectre solaire*, a detailed map of the Sun's spectrum, identifying hydrogen lines and laying the foundation for astrophysics.
- **Ångström Unit (1868)**: Defined the ångström (10⁻¹⁰ meters) as a unit of wavelength, critical for measuring atomic and molecular scales.
- **Uppsala Astronomical Observatory**: Served as director, advancing astronomical research in Sweden.
- **Thermal Conductivity Studies**: Conducted early experiments on heat transfer, contributing to thermal physics.

## FAQs
### **What is Anders Jonas Ångström best known for?**
Ångström is best known for his work in spectroscopy, particularly his 1862 map of the Sun's spectrum, which identified hydrogen and established spectroscopy as a key tool in astronomy and physics.

### **What is the ångström unit, and why is it important?**
The ångström (Å) is a unit of length equal to 0.1 nanometers, used to measure wavelengths of light and atomic distances. It remains essential in crystallography, chemistry, and nanotechnology.

### **Where did Anders Jonas Ångström work?**
He spent his career at Uppsala University, where he was a professor of physics and director of the Uppsala Astronomical Observatory.

### **What awards did Anders Jonas Ångström receive?**
He was awarded the Rumford Medal by the Royal Society for his discoveries in optical properties of matter.

### **How did Ångström influence modern science?**
His spectroscopic techniques enabled the study of stellar composition, while the ångström unit became a standard in atomic-scale measurements, influencing fields from quantum physics to materials science.

## Why They Matter
Ångström revolutionized spectroscopy, bridging astronomy and physics by proving that celestial bodies could be chemically analyzed through light. His unit of measurement became indispensable in scientific research, and his methods laid the groundwork for modern astrophysics and quantum mechanics.

## Notable For
- **Pioneering Spectroscopy**: First to identify hydrogen in the Sun’s spectrum.
- **Ångström Unit**: Defined a fundamental unit of wavelength (0.1 nm).
- **Rumford Medal (1872)**: Awarded by the Royal Society for thermal/optical discoveries.
- **Director of Uppsala Observatory**: Advanced Swedish astronomical research.
- **Legacy in Physics**: His name is immortalized in the ångström unit and lunar crater *Ångström*.

## Body
### **Early Life and Education**
Anders Jonas Ångström was born on August 13, 1814, in Lögdö, Sweden. He studied physics at Uppsala University, earning his PhD and later becoming a professor there.

### **Career and Research**
Ångström’s career centered on Uppsala University, where he taught physics and directed the Uppsala Astronomical Observatory. His 1862 publication *Recherches sur le spectre solaire* was a landmark in spectroscopy, mapping the Sun’s spectrum and identifying hydrogen lines. This work proved that the same elements exist on Earth and in stars, a foundational insight for astrophysics.

### **Legacy and Honors**
The ångström unit (Å), defined as 10⁻¹⁰ meters, became a standard in science. Ångström received the Rumford Medal in 1872 for his contributions to thermal and optical physics. His influence extends to modern astronomy, where his techniques are still used to analyze stellar composition. A lunar crater and asteroid (42487 Ångström) bear his name, honoring his enduring impact.

### **Affiliations and Memberships**
Ångström was a member of the Royal Swedish Academy of Sciences, the Royal Society (UK), and the French Academy of Sciences, reflecting his international recognition. His work at Uppsala University cemented its reputation in physics and astronomy.

### **Death and Commemoration**
Ångström died on June 21, 1874, in Uppsala. His contributions are commemorated in scientific units, celestial namesakes, and his foundational role in spectroscopy.

## References

1. [Lögdö kyrkoarkiv, Födelse- och dopböcker, SE/HLA/1010120/C/2 (1766-1841), bildid: A0005183_00049. Swedish church birth records](https://sok.riksarkivet.se/bildvisning/A0005183_00049#?c=&m=&s=&cv=48&xywh=2714%2C1303%2C2423%2C1357)
2. Integrated Authority File
3. ResearchGate
4. [Uppsala domkyrkoförsamlings kyrkoarkiv, Död- och begravningsböcker, SE/ULA/11632/F/7 (1874-1879), bildid: 80002756_00022. burial register](https://sok.riksarkivet.se/bildvisning/80002756_00022#?c=&m=&s=&cv=21&xywh=379%2C4593%2C2151%2C1489)
5. datos.bne.es
6. NNDB
7. [Source](http://www.nndb.com/org/793/000055628/)
8. [Svenskagravar.se](https://www.svenskagravar.se/gravsatt/d0053759-4adc-464d-a11b-462990b0daa8)
9. [Anders Jonas Ångström 1814–1874  Fysiker. Church of Sweden](https://kulturpersoner.uppsalakyrkogardar.se/anders-jonas-angstrom/)
10. [Source](https://royalsociety.org/grants-schemes-awards/awards/rumford-medal/)
11. Complete List of Royal Society Fellows 1660-2007
12. Mathematics Genealogy Project
13. International Standard Name Identifier
14. Brockhaus Enzyklopädie
15. Gran Enciclopèdia Catalana
16. GeneaStar
17. Proleksis Encyclopedia
18. Croatian Encyclopedia
19. Freebase Data Dumps. 2013
20. Virtual International Authority File
21. IdRef
22. CERL Thesaurus
23. La France savante
24. LIBRIS. 2012
25. FactGrid