Pulsar
PSR J1909-3744
Millisecond pulsar · binary system
A millisecond pulsar spinning 339 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 1.533 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 | Corona Australis |
| Period | 2.947 ms (339 Hz) |
| Period derivative | 1.4×10⁻²⁰ s/s |
| Characteristic age | 3.3 billion years |
| Magnetic field | 2.1×10⁸ G |
| Spin-down luminosity | 2.2×10³⁴ erg/s |
| Dispersion measure | 10.4 pc/cm³ |
| Distance | 1,140 pc (3.7 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.23 M☉ |
| Orbital period | 1.533 days |
| Eccentricity | 0.000000 |
| Discovery | 2003 · pkssw, gbncc |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 19h 09m 47.4s |
| Declination (J2000) | −37° 44′ 15″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 52° N. South of latitude 52° S it never sets. 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 around 1693 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 66 million years.