Pulsar
PSR B1819-22 (J1822-2256)
Radio pulsar
A neutron star spinning once every 1.87 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 | Sagittarius |
| Period | 1.874 s |
| Period derivative | 1.4×10⁻¹⁵ s/s |
| Characteristic age | 22 million years |
| Magnetic field | 1.6×10¹² G |
| Spin-down luminosity | 8.1×10³⁰ erg/s |
| Dispersion measure | 121.2 pc/cm³ |
| Distance | 3,261 pc (10.6 thousand ly) |
| Discovery | 1972 · jb1, htru_pks, mol2, pks70, pksmb |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 18h 22m 58.9s |
| Declination (J2000) | −22° 56′ 31″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 67° N. South of latitude 67° S 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 11 thousand years ago. At that time the first farming villages were being founded; there was no writing yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 189 million years.