Pulsar
PSR B1917+00 (J1919+0021)
Radio pulsar
A neutron star spinning once every 1.27 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 | Aquila |
| Period | 1.272 s |
| Period derivative | 7.7×10⁻¹⁵ s/s |
| Characteristic age | 2.6 million years |
| Magnetic field | 3.2×10¹² G |
| Spin-down luminosity | 1.5×10³² erg/s |
| Dispersion measure | 90.2 pc/cm³ |
| Distance | 5,600 pc (18.3 thousand ly) |
| Discovery | 1972 · jb1, ar4, gb2, gb3, lotaas, misc, mol2, pks70, pkssw, fast_gpps |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 19h 19m 50.7s |
| Declination (J2000) | +0° 21′ 40″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 90° N. It stands highest at midnight in July, 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 324 million years.