Pulsar
PSR B1657-13 (J1659-1305)
Radio pulsar
A neutron star spinning once every 0.641 seconds; the beams from its magnetic poles sweep across Earth on every turn. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Ophiuchus |
| Period | 641.0 ms |
| Period derivative | 6.2×10⁻¹⁶ s/s |
| Characteristic age | 16 million years |
| Magnetic field | 6.4×10¹¹ G |
| Spin-down luminosity | 9.3×10³¹ erg/s |
| Dispersion measure | 60.4 pc/cm³ |
| Distance | 484 pc (1.6 thousand ly) |
| Discovery | 1985 · gb2, pks70 |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 16h 59m 53.1s |
| Declination (J2000) | −13° 05′ 09″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 77° N. South of latitude 77° S it never sets. It stands highest at midnight in June, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 447. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 28 million years.