A planetary companion for 51 Pegasi implied by absence of pulsations in the stellar spectra

Article metrics

Abstract

Systematic variations in the Doppler shifts of absorption lines in the spectrum of the star 51 Pegasi were interpreted as indicating the presence of a planet about half the mass of Jupiter, very close to the star1,2. But that interpretation was called into question when variations in the line shapes that tracked the apparent orbital phase were reported3,4; this suggested that a planet was an inadequate explanation of the radial-velocity data. Here I report results from recent monitoring of 51 Peg; the oscillations I previously published are not evident in the new data. When combined with two other high-precision observations of 51 Peg (57), that also see no changes in line shape, a planet may indeed be the best explanation for the radial-velocity results.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: The periodogram of the bisector curvature for the frequency range 0.0–1.0 cycles d−1.

References

  1. 1

    Mayor, M. & Queloz, D. AJupiter-mass companion to a solar-type star. Nature 378, 355–359 (1995).

  2. 2

    Marcy, G. W. et al. The planet around 51 Pegasi. Astrophys. J. 481, 926–935 (1997).

  3. 3

    Gray, D. F. Absence of a planetary signature in the spectra of the star 51 Pegasi. Nature 385, 795–796 (1997).

  4. 4

    Gray, D. F. & Hatzes, A. P. Non-radial oscillation in the solar-temperature star 51 Pegasi. Astrophys. J. 490, 412–424 (1997).

  5. 5

    Hatzes, A. P., Cochrane, W. D. & Bakker, E. J. Further evidence for the planet around 51 Pegasi. Nature 391, 154–156 (1998).

  6. 6

    Brown, T. M. et al. Asearch for line shape and depth variations in 51 Pegasi and τ Boötis. Astrophys. J. (submitted).

  7. 7

    Brown, T. M. et al. Exoplanets or dynamic atmospheres? The radial velocity and line shape variations of 51 Pegasi and τ Boötis. Astrophys. J. Suppl. Ser. (submitted).

  8. 8

    Gray, D. F. Lectures on Spectral-Line Analysis: F, G and K Stars Ch. 4 (Arva, Ontario, (1988)).

  9. 9

    Gray, D. F. & Desikachary, K. Anew approach to periodogram analyses. Astrophys. J. 181, 523–530 (1973).

  10. 10

    Gray, D. F. Spectral line-depth ratios as temperature indicators in cool stars. Publ. Astron. Soc. Pacif. 106, 1248–1257 (1994).

Download references

Acknowledgements

This work was supported by the Natural Sciences and Engineering Research Council of Canada.

Author information

Correspondence to David F. Gray.

Rights and permissions

Reprints and Permissions

About this article

Further reading

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.