← Back to Training
MCQIntermediateGalaxies & Large-Scale Structure
USAAAO — 2022 First Round
Question 29
An astronomer takes a spectrum of a galaxy and observes that the hydrogen-alpha emission line is at a wavelength of 721.9 nanometers. In a laboratory on Earth, this same emission line is observed at a wavelength of 656.3 nanometers. Approximately what is the (proper) distance to this galaxy?
Sign in to save your progress.
Source
USAAAO 2022 First Round. Question text, choices, and answer were transcribed from the official USAAAO exam and solutions PDFs.