Abstract
IN a previous article1 we reported long-baseline interferometer measurements of several quasi-stellar radio sources using stations of the NASA/JPL Deep Space Network in Australia and California. Comparison of three sets of similar observations now shows evidence for secular variations in the apparent intensities of small-diameter components in several of these objects. The results are compatible with the theory of expanding synchrotron sources, but an apparent expansion velocity greater than that of light seems to be required for the recent outburst in 3C 273.
Similar content being viewed by others
References
Gubbay, J., Legg, A. J., Robertson, D. S., Moffet, A. T., and Seidel, B., Nature, 222, 730 (1969).
Kellermann, K. I., and Pauliny-Toth, I. I. K., Ann. Revs. Astron. Astrophys., 6, 417 (1966).
Kellermann, K. I., Clark, B. G., Bare, C. C., Rydbeck, O., Ellder, J., Hansson, B., Kollberg, E., Hoglund, B., Cohen, M., and Jauncey, D. L., Astrophys. J. Lett., 153, L209 (1968).
Rees, M., Mon. Not. Roy. Astron. Soc., 135, 345 (1967).
Locke, J. L., Andrew, B. H., and Medd, W. J., Astrophys. J. Lett., 157, L81 (1969).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
GUBBAY, J., LEGG, A., ROBERTSON, D. et al. Variations of Small Quasar Components at 2,300 MHz. Nature 224, 1094–1095 (1969). https://doi.org/10.1038/2241094b0
Received:
Issue Date:
DOI: https://doi.org/10.1038/2241094b0
- Springer Nature Limited
This article is cited by
-
Radio observations of active galactic nuclei with mm-VLBI
The Astronomy and Astrophysics Review (2017)
-
Faster-than-light motion in quasars
Journal of Astrophysics and Astronomy (1984)
-
Radio emission of extragalactic objects
Astrophysics (1981)