|
A planetary system around the millisecond pulsar PSR1257 + 12 A. Wolszczan* & D. A. Frail†
*National Astronomy and Ionosphere Center, Arecibo Observatory, Arecibo, Puerto Rico 00613, USA
†National Radio Astronomy Observatory, Socorro, New Mexico 87801, USA
MILLISECOND radio pulsars, which are old (~109yr), rapidly
rotating neutron stars believed to be spun up by accretion of matter from their
stellar companions, are usually found in binary systems with other degenerate
stars1. Using the 305-m Arecibo radiotelescope to make
precise timing measurements of pulses from the recently discovered 6.2-ms
pulsar PSR1257 +12 (ref. 2), we demonstrate that, rather than being associated
with a stellar object, the pulsar is orbited by two or more planet-sized
bodies. The planets detected so far have masses of at least 2.8
M
and 3.4 M
where M is the mass
of the Earth. Their respective distances from the pulsar are 0.47 AU and 0.36 AU,
and they move in almost circular orbits with periods of 98.2 and 66.6 days.
Observations indicate that at least one more planet may be present in this
system. The detection of a planetary system around a nearby (~500 pc),
old neutron star, together with the recent report on a planetary companion to
the pulsar PSR1829–10 (ref. 3) raises the tantalizing possibility that a
non-negligible fraction of neutron stars observable as radio pulsars may
be orbited by planet-like bodies.
References
1. |
Bhattacharya, D. & van den Heuvel, E. P. J. Phys. Rep. 203, 1−124 (1991). | Article | ISI | ChemPort | |
2. |
Wolszczan, A. IAU Circ. No. 5073 (1990). |
3. |
Bailes, M., Lyne, A. G. & Shemar, S. L. Nature 352, 311−313 (1991). | Article | ISI | |
4. |
Wolszczan, A. Nature 350, 688−690 (1991). | Article | |
5. |
Taylor, J. H. & Weisberg, J. M. Astrophys. J. 345, 434−450 (1989). | Article | |
6. |
Davis, M. M., Taylor, J. H., Weisberg, J. M. & Backer, D. C. Nature 315, 547−550 (1985). | Article | ISI | |
7. |
Alpar, M. A., Nandkumar, R. & Pines, D. Astrophys. J. 311, 197−213 (1986). | Article | |
8. |
Fruchter, A. S., Stinebring, D. R. & Taylor, J. H. Nature 333, 237−239 (1988). | Article | |
9. |
Lyne, A. G. et al. Nature 347, 650−652 (1990). | Article | |
10. |
Shaham, J. Astrophys. J. 214, 251−260 (1977). | Article | ISI | ChemPort | |
11. |
Nelson, R. W., Finn, L. S. & Wasserman, I. Astrophys. J. 348, 226−231 (1990). | Article | |
12. |
Peale, S. J. Ann. Rev. Astr. Astrophys. 14, 215−246 (1976). | Article | ISI | |
13. |
Dermott, S. F. & Nicholson, P. D. Nature 319, 115−120 (1986). | Article | |
14. |
Vilas, F. in Mercury (eds Vilas, F., Chapman, C. R. & Matthews, M. S.) 59−76 (University of Arizona Press, Tucson, 1988). |
15. |
Richards, D. W., Pettengill, G. H., Counselman, C. C. III & Rankin, J. M. Astrophys. J. 160, L1−6 (1970). | Article | |
16. |
Demiaski, M. & Prszyski, M. Nature 282, 383−385 (1979). |
17. |
Podsiadlowski, Ph., Pringle, J. E. & Rees, M. J. Nature 352, 783−784 (1991). | Article | |
18. |
Fabian, A. C. & Podsiadlowski, Ph. Nature 353, 801−801 (1991). | Article | PubMed | |
19. |
Lin, D. N. C., Woosley, S. E. & Bodenheimer, P. H. Nature 353, 827−829 (1991). | Article | |
20. |
Krolik, J. H. Nature 353, 829−831 (1991). | Article | |
21. |
Wasserman, I., Cordes, J. M., Finn, L. S. & Nelson, R. W. Cornell Univ. preprint (1991). |
22. |
Nakano, T. Mon. Not. R. astr. Soc. 224, 107−130 (1987). |
23. |
Shu, F. H., Lubow, S. H. & Anderson, L. Astrophys. J. 29, 223−241 (1979). |
24. |
Rudak, B. & Paczyski, B. Acta Astr. 31, 13−24 (1981). |
25. |
Ryba, M. F. & Taylor, J. H. Astrophys. J. 380, 557−563 (1991). | Article | |
26. |
Black, D. C. Space Sci. Rev. 25, 35−81 (1980). |
© 1992 Nature Publishing Group Privacy Policy |