Pulsar
PSR J1917+0615_P
Millisecond pulsar · binary system
A millisecond pulsar spinning 252 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. It shares a 4.618 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 | 3.968 ms (252 Hz) |
| Period derivative | 2.1×10⁻²⁰ s/s |
| Characteristic age | 3.0 billion years |
| Magnetic field | 2.9×10⁸ G |
| Spin-down luminosity | 1.3×10³⁴ erg/s |
| Dispersion measure | 172.5 pc/cm³ |
| Distance | 8,159 pc (26.6 thousand ly) |
| Companion | helium white dwarf (estimated), ~0.20 M☉ |
| Orbital period | 4.618 days |
| Eccentricity | 0.000046 |
| Discovery | 2025 · fast_gpps |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 19h 17m 20.3s |
| Declination (J2000) | +6° 15′ 29″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 84° 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 27 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 472 million years.