Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

First observation of a quasar with a redshift of 4

Abstract

Quasars of high redshift (here z > 3.3) are the most distant objects known and provide direct information on the early Universe. However, only a few high-redshift quasars have been discovered and their detection remains problematic. We report here the discovery of a quasar (0046 – 293) with a redshift z = 4.01 and another (0044–276) with a redshift z =3.42. The redshift of the former quasar is the highest yet detected and compares with the z = 3.80 of the previous most distant known quasar1. The new quasars lie in the same field as three other known high-redshift quasars1,2 and were identified in a preliminary analysis of new multi-colour data derived from measurements of direct photographic plates taken with the United Kingdom Schmidt Telescope (UKST). The two new quasars are significantly fainter (mR>19) than previously known high-redshift quasars discovered by optical techniques, and demonstrate that the luminosity function of optically selected high-redshift quasars extends over at least two· magnitudes.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

References

  1. Hazard, C., McMahon, R. G. & Sargent, W. L. W. Nature 322, 38–40 (1986).

    Article  ADS  CAS  Google Scholar 

  2. Shanks, T., Fong, R. & Boyle, B. J. Nature 303, 156–158 (1983).

    Article  ADS  Google Scholar 

  3. Osmer, P. S. Astrophys. J. 253, 28–37 (1982).

    Article  ADS  CAS  Google Scholar 

  4. Schmidt, M., Schneider, D. P. & Gunn, J. E. Astrophys. J. 310, 518–533 (1986).

    Article  ADS  CAS  Google Scholar 

  5. Koo, D. C., Kron, R. G. & Cudworth, K. M. Publ. astr. Soc. Pac. 98, 285–306 (1986).

    Article  ADS  CAS  Google Scholar 

  6. Boyle, B. J., Fong, R., Shanks, T. & Peterson, B. A. Mon. Not. R. astr. Soc. (in the press).

  7. Kibblewhite, E. J., Bridgeland, M. T., Bunclark, P. S. & Irwin, M. J. Proc. Astronomical Microdensitometry Conf., 277–287 (NASA, Washington DC, 1983).

    Google Scholar 

  8. Bunclark, P. S. & Irwin, M. J. Proc. Statistical Methods in Astronomy Symp., Strasbourg 195–200 (ESA SP-201, 1983).

    Google Scholar 

  9. Irwin, M. J., McMahon, R. G. & Hewett, P. C. Measuring Machines, 5–6 (Newslett. No. 8. SERC, London, 1985).

    Google Scholar 

  10. UKSTU Handbook (Royal Observatory, Edinburgh, 1983).

  11. Sargent, W. L. W., Filippenko, A. V., Steidel, C. C., Hazard, C. & McMahon, R. G. Nature 322, 40–42 (1986).

    Article  ADS  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Warren, S., Hewett, P., Irwin, M. et al. First observation of a quasar with a redshift of 4. Nature 325, 131–133 (1987). https://doi.org/10.1038/325131a0

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/325131a0

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing