Pulsar
PSR B1809-176 (J1812-1733)
Radio pulsar
A neutron star spinning once every 0.538 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 | 538.3 ms |
| Period derivative | 9.8×10⁻¹⁶ s/s |
| Characteristic age | 8.7 million years |
| Magnetic field | 7.4×10¹¹ G |
| Spin-down luminosity | 2.5×10³² erg/s |
| Dispersion measure | 509.8 pc/cm³ |
| Distance | 4,514 pc (14.7 thousand ly) |
| Discovery | 1987 · jb2, htru_pks, misc, pksmb |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 18h 12m 15.9s |
| Declination (J2000) | −17° 33′ 38″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 72° N. South of latitude 72° 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 15 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 261 million years.