Pulsar
PSR J1845+0317_P
Millisecond pulsar · binary system
A millisecond pulsar spinning 540 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 4.56 h orbit with a very-low-mass companion. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Serpens |
| Period | 1.851 ms (540 Hz) |
| Period derivative | 2.8×10⁻²⁰ s/s |
| Characteristic age | 1.0 billion years |
| Magnetic field | 2.3×10⁸ G |
| Spin-down luminosity | 1.8×10³⁵ erg/s |
| Dispersion measure | 77.3 pc/cm³ |
| Distance | 2,799 pc (9.1 thousand ly) |
| Companion | very-low-mass companion (estimated), ~0.007 M☉ |
| Orbital period | 4.56 h |
| Eccentricity | 0.0037 |
| Discovery | 2025 · fast_gpps |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 18h 45m 22.9s |
| Declination (J2000) | +3° 17′ 19″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 87° S. 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 9,129 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 162 million years.