Pulsar
PSR J1900+0308
Millisecond pulsar · binary system
A millisecond pulsar spinning 204 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 12.476 days orbit with a helium white dwarf. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Aquila |
| Period | 4.909 ms (204 Hz) |
| Period derivative | 5.9×10⁻²¹ s/s |
| Characteristic age | 13.2 billion years |
| Magnetic field | 1.7×10⁸ G |
| Spin-down luminosity | 2.0×10³³ erg/s |
| Dispersion measure | 249.9 pc/cm³ |
| Distance | 4,801 pc (15.7 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.20 M☉ |
| Orbital period | 12.476 days |
| Discovery | 2012 · palfa |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 19h 00m 50.5s |
| Declination (J2000) | +3° 08′ 24″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 87° S. 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 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 278 million years.