Concept information
Preferred term
21-centimeter line
Definition
- The emission line of neutral hydrogen in interstellar clouds. It lies in the radio spectrum at wavelength of about 21 cm, frequency 1420 MHz. Its existence was predicted by Hendrik van de Hulst in 1944 and discovered by Harold Ewen and Edward Purcell in 1951. (An Etymological Dictionary of Astronomy and Astrophysics, by M. Heydari-Malayeri, https://dictionary.obspm.fr/index.php?formSearchTextfield=21+cm+line&formSubmit=Search&showAll=1)
Broader concept
Entry terms
- 21 cm line
- H I line
- hydrogen line
In other languages
-
French
URI
http://data.loterre.fr/ark:/67375/MDL-TR51S08S-8
{{label}}
{{#each values }} {{! loop through ConceptPropertyValue objects }}
{{#if prefLabel }}
{{/if}}
{{/each}}
{{#if notation }}{{ notation }} {{/if}}{{ prefLabel }}
{{#ifDifferentLabelLang lang }} ({{ lang }}){{/ifDifferentLabelLang}}
{{#if vocabName }}
{{ vocabName }}
{{/if}}