Pulsar
PSR J1740-5340A
Millisecond pulsar · in the globular cluster NGC6397
A millisecond pulsar spinning 274 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 1.354 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 | Ara |
| Period | 3.650 ms (274 Hz) |
| Period derivative | 1.7×10⁻¹⁹ s/s |
| Characteristic age | 344 million years |
| Magnetic field | 7.9×10⁸ G |
| Spin-down luminosity | 1.4×10³⁵ erg/s |
| Dispersion measure | 71.8 pc/cm³ |
| Distance | 2,482 pc (8.1 thousand ly) |
| Location | in the globular cluster NGC6397 |
| Companion | helium white dwarf (estimated), ~0.22 M☉ |
| Orbital period | 1.354 days |
| Discovery | 2001 · pksgc |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 17h 40m 44.6s |
| Declination (J2000) | −53° 40′ 41″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 36° N. South of latitude 36° 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 8,095 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 144 million years.