Pulsar
PSR J1811-2405
Millisecond pulsar · binary system
A millisecond pulsar spinning 376 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 6.272 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 | Sagittarius |
| Period | 2.661 ms (376 Hz) |
| Period derivative | 1.4×10⁻²⁰ s/s |
| Characteristic age | 3.1 billion years |
| Magnetic field | 1.9×10⁸ G |
| Spin-down luminosity | 2.9×10³⁴ erg/s |
| Dispersion measure | 60.6 pc/cm³ |
| Distance | 1,389 pc (4.5 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.27 M☉ |
| Orbital period | 6.272 days |
| Eccentricity | 0.000001 |
| Discovery | 2010 · htru_pks, FermiBlind |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 18h 11m 19.8s |
| Declination (J2000) | −24° 05′ 19″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 66° N. South of latitude 66° 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 4,530 years ago. At that time the first farming villages were being founded; there was no writing yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 80 million years.