Pulsar
PSR B1516+02B (J1518+0204B)
Millisecond pulsar · in the globular cluster M5(NGC5904)
A millisecond pulsar spinning 126 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 6.858 days orbit with a helium white dwarf. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Serpens |
| Period | 7.947 ms (126 Hz) |
| Dispersion measure | 29.5 pc/cm³ |
| Distance | 7,480 pc (24.4 thousand ly) |
| Location | in the globular cluster M5(NGC5904) |
| Companion | helium white dwarf (estimated), ~0.13 M☉ |
| Orbital period | 6.858 days |
| Eccentricity | 0.1378 |
| Discovery | 1989 · misc |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 15h 18m 31.5s |
| Declination (J2000) | +2° 05′ 15″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 88° S. It stands highest at midnight in May, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 24 thousand years ago. At that time Homo sapiens was spreading out of Africa; there was no farming yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 433 million years.