Letter | Published:

Optical Variation of 3C 446

Naturevolume 214pages256257 (1967) | Download Citation



THE observations of Sandage1 and of Kinman et al.2 have shown that the optical brightness of the quasar 3C 446 is variable. This quasar has been observed as part of a programme of optical monitoring of quasars at the Royal Greenwich Observatory. Our results show a continuation of the earlier behaviour and lead to the speculation that the variation is caused by the occultation of the quasar by absorbing clouds in its vicinity.

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  1. 1

    Sandage, A. R., Intern. Astro. Union, Circ. No. 1961 (1966).

  2. 2

    Kinman, T. D., Lamla, E., and Wirtanen, C. A., Astrophys. J., 146, 964 (1966).

  3. 3

    Goldsmith, D. W., and Kinman, T. D., Astrophys. J., 142, 1693 (1965).

  4. 4

    Penston, M. V., and Cannon, R. D., Intern. Astro. Union, Circ. No. 2000 (1967).

  5. 5

    Sandage, A. R., Westphal, J. A., and Strittmatter, P. A., Astrophys. J., 146, 322 (1966).

  6. 6

    Burbidge, E. M., Burbidge, G. R., Hoyle, F., and Lynds, C. R., Nature, 210, 774 (1966).

  7. 7

    Burbidge, E. M., and Burbidge, G. R., Astrophys. J., 143, 271 (1966).

  8. 8

    Burbidge, E. M., Lynds, C. R., and Burbidge, G. R., Astrophys. J., 144, 447 (1966).

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  1. Royal Greenwich Observatory, Herstmonceux Castle, Hailsham, Sussex

    • R. D. CANNON
    •  & M. V. PENSTON


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