Einstein Ring 4C 05.51

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About this Image

This radio source, 4C 05.51, has extremely unusual structure: a smooth low-surface brightness ring accompanied by two nearly diametrically opposed-compact sources, both offset to the southwest; The optical and radio spectral properties appear inconsistent with a Supernova Remnant or an HII Region, astronomical systems that sometimes display ring-like structure. The structure strongly suggests that it is due to gravitational lensing, by a foreground massive object of light from a Quasar or Radio Galaxy. If this is the case, then this object represents an "Einstein Ring", a particularly symmetric case of gravitational lensing first proposed by Einstein in 1936, in which the source is imaged into a ring. Further observations are being carried out to test the lens hypothesis.

Investigator(s):  J.N. Hewitt and E.L. Turner

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Technical Data

    Telescope VLA 
    Date of Observation 1987-09-20 
    Type of Observation Continuum Observations 
    Band U 
    Wavelength 2.0 cm 
    Frequency 15 GHz 
    Center of Image RA: 11:31:56.47, Dec: 04:55:48.80 (J2000)  
    Field of View 0.0014 x 0.0014 degrees  
    Technical Caption VLA in A-configuration using 26 antennas.  

  • Astronomical database entries for 4C 05.51
    • Query NED for images of 4C 05.51
    • Query SIMBAD for more 4C 05.51 data


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