Magnitudes, distance moduli, bolometric corrections, and so much more

2022/06/02 by David W. Hogg, Hogg, David W.
Physics and Astronomy · #FOS: Physical sciences #Historical Astronomy and Related Studies #History and Developments in Astronomy #Instrumentation and Methods for Astrophysics (astro-ph.IM) #Popular Physics (physics.pop-ph)

paper · pdf · doi:10.48550/arxiv.2206.00989

openalex publication_date 2022/06/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

This pedagogical document about stellar photometry - aimed at those for whom astronomical arcana seem arcane - endeavours to explain the concepts of magnitudes, color indices, absolute magnitudes, distance moduli, extinctions, attenuations, color excesses, K corrections, and bolometric corrections. I include some discussion of observational technique, and some discussion of epistemology, but the primary focus here is on the theoretical or interpretive connections between the observational astronomical quantities and the physical properties of the observational targets.

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