Pulsar
PSR J1618-3921
Millisecond pulsar · binary system
A millisecond pulsar spinning 83 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 22.746 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 | Scorpius |
| Period | 11.987 ms (83 Hz) |
| Period derivative | 5.4×10⁻²⁰ s/s |
| Characteristic age | 3.5 billion years |
| Magnetic field | 8.1×10⁸ G |
| Spin-down luminosity | 1.2×10³³ erg/s |
| Dispersion measure | 118.0 pc/cm³ |
| Distance | 5,515 pc (18.0 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.20 M☉ |
| Orbital period | 22.746 days |
| Eccentricity | 0.0274 |
| Discovery | 2001 · pkssw |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 16h 18m 18.8s |
| Declination (J2000) | −39° 21′ 02″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 51° N. South of latitude 51° S it never sets. 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 18 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 319 million years.