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Updated: Jul 31, 2026
10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
Hubble's diagram and cosmic expansion.
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. kirshner@cfa.harvard.edu
Summary
Edwin Hubble's 1929 paper established that galaxy distance is proportional to redshift, a foundational concept in cosmology. This discovery paved the way for understanding the expanding, evolving, and accelerating universe.
Area of Science:
- Cosmology
- Astronomy
Background:
- Edwin Hubble's 1929 article in PNAS introduced a groundbreaking relationship between galaxy distance and redshift.
- The findings are fundamental to modern cosmology, influencing terms like the Hubble constant and Hubble's Law.
Purpose of the Study:
- To analyze the significance of Edwin Hubble's 1929 publication on the expanding universe.
- To highlight the article's foundational role in cosmology despite historical limitations in data and interpretation.
Main Methods:
- Analysis of Edwin Hubble's 1929 PNAS article.
- Review of the historical context and impact of Hubble's findings on cosmological models.
Main Results:
- Hubble's chief result demonstrated a direct proportionality between a galaxy's distance and its redshift.
- The article laid the groundwork for the study of the expanding, evolving, and accelerating universe.
Conclusions:
- Despite systematic errors in distance measurements and alternative early interpretations, Hubble's work remains a cornerstone of cosmology.
- The article's legacy is its pivotal role in initiating the scientific investigation of cosmic expansion.
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