Pulsar
PSR J0102+4839
Millisecond pulsar · binary system
A millisecond pulsar spinning 337 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 1.672 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 | Andromeda |
| Period | 2.964 ms (337 Hz) |
| Period derivative | 1.1×10⁻²⁰ s/s |
| Characteristic age | 4.1 billion years |
| Magnetic field | 1.9×10⁸ G |
| Spin-down luminosity | 1.7×10³⁴ erg/s |
| Dispersion measure | 53.5 pc/cm³ |
| Distance | 2,310 pc (7.5 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.21 M☉ |
| Orbital period | 1.672 days |
| Discovery | 2011 · FermiAssoc, gbt350 |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 1h 02m 50.7s |
| Declination (J2000) | +48° 39′ 43″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 41° S. North of latitude 41° N it never sets. It stands highest at midnight in October, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 7,534 years ago. At that time the first farming villages were being founded; there was no writing yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 134 million years.