PSR B1620-26
PSR B1620-26 is a white dwarf companion in orbit around a millisecond pulsar, (PSR 1620-26) located within the globular cluster M4 (NGC 6121). Measurements using the pulsar timing method indicate that the white dwarf is orbited by three massive planets.1, 2
Pulsar | |
---|---|
Distance | 12,400 light-years (3.8 kpc) |
Period | 11 milliseconds (= 90 rev/s) |
Planets | |||
---|---|---|---|
a | b | c | |
Mass (Jupiter = 1) | 1.2 | 3.4 | 6.7 |
Semimajor axis | ~10 | 30 | 64 |
Orbital period (years) | 61.8 | 129 | 389 |
Eccentricity | 0.0 | 0.2 | 0.5 |
References
1. Rasio, F. A. "New Evidence for a Planet or Brown Dwarf in Orbit Around
PSR M1620-26." In A. Olinto et al., eds., Proceedings of the Texas
Symposium on Relativistic Astrophysics, Annals of the New York Academy
of Science (1998).
2. Thorsett, S., Arzoumanian, Z., Camilo, F., and Lyne, A. "The Triple
Pulsar System PSR B1620-26 in M4," Astrophysical Journal (submitted
1999).