Detection of Interstellar OH in Two External Galaxies,

Abstract

Molecular OH lines at 1665 and 1667 MHz have been detected in absorption in the spiral galaxy NGC 253 and the irregular galaxy M82. This is the first time interstellar molecular lines, whether radio or optical, have been observed outside the Galaxy. Observations were made with the Owens Valley interferometer, thus the amplitude and phase of the absorption features could both be measured. The run of phase versus velocity agrees with the sense of rotation of both galaxies. Abundances close to those found in the Galaxy are derived; however this comparison is not very meaningful because of possible differences in excitation conditions. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1971
Accession Number
AD0724763

Entities

People

  • L. Weliachew

Organizations

  • Owens Valley Radio Observatory

Tags

DTIC Thesaurus Topics

  • Absorption
  • Amplitude
  • Detection
  • Excitation
  • Interferometers
  • Motion
  • Observation
  • Rotation

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering

Technology Areas

  • Space