Eddington

Definition

Sir Arthur Eddington was an English astrophysicist who played a pivotal role in the development and understanding of stellar structure and evolution. He is known for his work on the Hertzsprung-Russell (H–R) Diagram and for providing observational confirmation of Einstein's General Theory of Relativity.

5 Must Know Facts For Your Next Test

1. Eddington demonstrated how pressure and temperature gradients within stars could maintain equilibrium, leading to our understanding of stellar structure.
2. He contributed significantly to the interpretation and application of the H-R Diagram by correlating stellar luminosities with their spectral types.
3. Eddington was instrumental in proving that stars are powered by nuclear fusion reactions occurring in their cores.
4. In 1919, he led an expedition that provided one of the first empirical confirmations of Einstein’s General Theory of Relativity by observing the deflection of starlight during a solar eclipse.
5. The Eddington limit, named after him, describes the maximum luminosity a star can achieve when there is balance between radiation pressure outward and gravitational forces inward.

Review Questions

• What is Eddington best known for in relation to stellar structure?
• How did Eddington contribute to our understanding of the H-R Diagram?
• What significant astronomical event did Eddington's expedition confirm in 1919?

Related terms

HRDiagram: A graph plotting individual stars as points with stellar luminosity on one axis and surface temperature or spectral class on the other.

NuclearFusion: The process by which multiple atomic nuclei join together to form a heavier nucleus, releasing energy; it powers stars.

GeneralTheoryofRelativity: Einstein's theory describing gravity as a property of space and time curvature caused by mass and energy.