Molecular gas content of the primaeval galaxy IRAS 10214+4724


THE faint IRAS source 10214 + 4724, identified1 with a distant galaxy at redshift z = 2.286, is one of the most intrinsically luminous objects in the Universe, with L≈1014 L (whereL is the solar luminosity). The remarkable detection of emission from neutral CO (ref. 2) leads, by comparison with similar detections in nearby galaxies, to an estimate of 2–6 x 1011M for the mass of neutral molecular hydrogen in this galaxy. This is 30–90 times less than the estimate given in ref. 2, but still comparable to the total mass (gas, dust and stars) of a large spiral galaxy. This gas mass is consistent with the dynamical mass of the galaxy inferred from the CO emission line-width. The CO line luminosity is twenty times larger than is seen in nearby (z < 0.3) ultra-luminous (L>3xl011 M) galaxies3–5. Although it is extremely gas-rich, with a higher CO luminosity than any other galaxy, the infrared to CO luminosity ratio of 10214 + 4724 is twice that of most infrared-luminous galaxies, and 30 times higher than that of normal spirals. Its infrared colours and high infrared/CO luminosity ratio indicate that 10214 + 4724 is similar to nearby ultra-luminous galaxies5 that are known to be merging. This galaxy is a primaeval molecular galaxy with the mass of a large spiral, but with most of the mass in molecular gas rather than stars.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    Rowan-Robinson, M. et al. Nature 351, 719–721 (1991).

  2. 2

    Brown, R. L. & Vanden Bout, P. A. Astr. J. 102, 1956–1959 (1991).

  3. 3

    Downes, D., Solomon, P. M. & Radford, S. J. E. in Dynamics of Galaxies and their Molecular Cloud Distributions (eds Combes, F. & Casoli, F.) 295–298 (Kluwer, Dordrecht, 1991).

  4. 4

    Radford, S. J. E., Solomon, P. M. & Downes, D. Astrophys. J. 369, L15–L18 (1991).

  5. 5

    Sanders, D. B., Soifer, B. T., Elias, J. H., Neugebauer, G. & Matthews, K. Astrophys. J. 328, L35–L39 (1988).

  6. 6

    Weinberg, S. Gravitation and Cosmology (Wiley, New York, 1972).

  7. 7

    Solomon, P. M. & Sage, L. J. Astrophys. J. 334, 613–625 (1988).

  8. 8

    Solomon, P. M., Radford, S. J. E. & Downes, D. Astrophys. J. 348, L53–L56 (1990).

  9. 9

    Solomon, P. M., Rivolo, A. R., Barrett, J. & Yahil, A. Astrophys. J. 319, 730–741 (1987).

  10. 10

    Scoville, N. Z. et al. Astrophys. J. Suppl. 63, 821–915 (1987).

  11. 11

    Scoville, N. Z., Sargent, A. I., Sanders, D. B. & Soifer, B. T. Astrophys. J. 366, L5–L9 (1991).

  12. 12

    Young, J. et al. Astrophys. J. 304, 443–458 (1986).

  13. 13

    Sanders, D. B. in Dynamics of Galaxies and their Molecular Cloud Distributions (eds Combes, F. & Casoli, F.) 417–423 (Kluwer, Dordrecht, 1991).

  14. 14

    Sanders, D. B. et al. Astr. Astrophys. 213, L5–L8 (1989).

  15. 15

    Kleinmann, S. G. et al. Astrophys. J. 328, 161–169 (1988).

  16. 16

    Solomon, P. M., Downes, D. & Radford, S. J. E. Astrophys. J. 387, L55–L61 (1992).

  17. 17

    Scoville, N. Z. & Young, J. S. Astrophys. J. 265, 148–165 (1983).

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Further reading


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.