Pulsar
PSR J1946+3417
Millisecond pulsar · binary system
A millisecond pulsar spinning 315 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 27.020 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 | Cygnus |
| Period | 3.170 ms (315 Hz) |
| Period derivative | 3.2×10⁻²¹ s/s |
| Characteristic age | 15.9 billion years |
| Magnetic field | 1.0×10⁸ G |
| Spin-down luminosity | 3.9×10³³ erg/s |
| Dispersion measure | 110.2 pc/cm³ |
| Distance | 6,938 pc (22.6 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.25 M☉ |
| Orbital period | 27.020 days |
| Eccentricity | 0.1345 |
| Discovery | 2013 · htru_eff, FermiAssoc, fast_gpps |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 19h 46m 25.1s |
| Declination (J2000) | +34° 17′ 15″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 56° S. North of latitude 56° N it never sets. It stands highest at midnight in July, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 23 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 401 million years.