Pulsar
PSR J0307+7443
Millisecond pulsar · binary system
A millisecond pulsar spinning 317 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 37.108 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 | Cassiopeia |
| Period | 3.156 ms (317 Hz) |
| Period derivative | 1.7×10⁻²⁰ s/s |
| Characteristic age | 2.9 billion years |
| Magnetic field | 2.4×10⁸ G |
| Spin-down luminosity | 2.2×10³⁴ erg/s |
| Dispersion measure | 6.3 pc/cm³ |
| Distance | 386 pc (1.3 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.23 M☉ |
| Orbital period | 37.108 days |
| Eccentricity | 0.0033 |
| Discovery | 2011 · FermiAssoc, gbt350 |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 3h 07m 55.9s |
| Declination (J2000) | +74° 43′ 13″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 15° S. North of latitude 15° N it never sets. It stands highest at midnight in November, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 767. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 22 million years.