Pulsar
PSR B1811+40 (J1813+4013)
Radio pulsar
A neutron star spinning once every 0.931 seconds; the beams from its magnetic poles sweep across Earth on every turn. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Hercules |
| Period | 931.1 ms |
| Period derivative | 2.5×10⁻¹⁵ s/s |
| Characteristic age | 5.8 million years |
| Magnetic field | 1.6×10¹² G |
| Spin-down luminosity | 1.2×10³² erg/s |
| Dispersion measure | 41.6 pc/cm³ |
| Distance | 4,915 pc (16.0 thousand ly) |
| Discovery | 1978 · gb1, gb4, lotaas |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 18h 13m 13.3s |
| Declination (J2000) | +40° 13′ 39″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 50° S. North of latitude 50° N it never sets. It stands highest at midnight in June, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 16 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 284 million years.