Pulsar
PSR J2129+1210J
Millisecond pulsar · in the globular cluster M15
A millisecond pulsar spinning 84 times per second: an old neutron star spun up again (“recycled”) by matter transferred from a companion. Period, spin-down, distance and orbit come from the ATNF Pulsar Catalogue; the beam geometry is illustrative.
| Type | Pulsar |
|---|---|
| Constellation | Pegasus |
| Period | 11.842 ms (84 Hz) |
| Period derivative | 2.0×10⁻¹⁹ s/s |
| Characteristic age | 919 million years |
| Magnetic field | 1.6×10⁹ G |
| Spin-down luminosity | 4.9×10³³ erg/s |
| Dispersion measure | 66.7 pc/cm³ |
| Distance | 25,000 pc (81.5 thousand ly) |
| Location | in the globular cluster M15 |
| Discovery | 2024 · misc |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 21h 29m 58.4s |
| Declination (J2000) | +12° 10′ 16″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 78° S. North of latitude 78° N it never sets. It stands highest at midnight in August, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 82 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 1.4 billion years.