First Measurements of Hydrogen Absorption in the Spectrum of a Radio Source


Paper graph showing hydrogen absorption in the spectrum of a radio source, obtained with the 50-foot radio telescope at the Naval Research Laboratory in Washington, D.C.

Ref: John Peter Hagen, A. Edward Lilley, and Edward F. McClain, "Absorption of 21-CM Radiation by Interstellar Hydrogen," The Astrophysical Journal 122 (Nov. 1955): 361-374.

Location: Currently not on view

See more items in: Medicine and Science: Physical Sciences


Exhibition Location:

Data Source: National Museum of American History

Id Number: PH.325761Catalog Number: 325761Accession Number: 257196

Object Name: graph

Measurements: overall: 9 1/2 in x 12 in; 24.13 cm x 30.48 cm


Record Id: nmah_1823136

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