Pulsar
PSR J2317+1439
Millisecond pulsar · binary system
A millisecond pulsar spinning 290 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 2.459 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 | Pegasus |
| Period | 3.445 ms (290 Hz) |
| Period derivative | 2.4×10⁻²¹ s/s |
| Characteristic age | 22.5 billion years |
| Magnetic field | 9.3×10⁷ G |
| Spin-down luminosity | 2.3×10³³ erg/s |
| Dispersion measure | 21.9 pc/cm³ |
| Distance | 1,667 pc (5.4 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.20 M☉ |
| Orbital period | 2.459 days |
| Eccentricity | 0.000001 |
| Discovery | 1993 · ar4, FermiBlind, gbncc |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 23h 17m 09.2s |
| Declination (J2000) | +14° 39′ 31″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 75° S. North of latitude 75° N it never sets. It stands highest at midnight in September, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 5,437 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 96 million years.