Pulsar
PSR B1237+25 (J1239+2453)
Radio pulsar
A neutron star spinning once every 1.38 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 | Coma Berenices |
| Period | 1.382 s |
| Period derivative | 9.6×10⁻¹⁶ s/s |
| Characteristic age | 23 million years |
| Magnetic field | 1.2×10¹² G |
| Spin-down luminosity | 1.4×10³¹ erg/s |
| Dispersion measure | 9.3 pc/cm³ |
| Distance | 840 pc (2.7 thousand ly) |
| Discovery | 1969 · gb1, ar327, ar4, gb4, lotaas |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 12h 39m 40.5s |
| Declination (J2000) | +24° 53′ 49″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 65° S. North of latitude 65° N it never sets. It stands highest at midnight in March, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around 715 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 49 million years.