Pulsar
PSR J1518+4904
Radio pulsar · binary system
A neutron star spinning once every 0.041 seconds; the beams from its magnetic poles sweep across Earth on every turn. It shares a 8.634 days orbit with a CO white dwarf. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Boötes |
| Period | 40.935 ms (24 Hz) |
| Period derivative | 2.7×10⁻²⁰ s/s |
| Characteristic age | 23.9 billion years |
| Magnetic field | 1.1×10⁹ G |
| Spin-down luminosity | 1.6×10³¹ erg/s |
| Dispersion measure | 11.6 pc/cm³ |
| Distance | 806 pc (2.6 thousand ly) |
| Companion | CO white dwarf (estimated), ~0.99 M☉ |
| Orbital period | 8.634 days |
| Eccentricity | 0.2495 |
| Discovery | 1996 · gb4, gbncc, lotaas |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 15h 18m 16.8s |
| Declination (J2000) | +49° 04′ 34″ |
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 May, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around 604 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 47 million years.