Pulsar
PSR J1831-3220B
Millisecond pulsar · in the globular cluster M69(NGC6637)
A millisecond pulsar spinning 208 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 | Sagittarius |
| Period | 4.800 ms (208 Hz) |
| Dispersion measure | 81.9 pc/cm³ |
| Distance | 3,743 pc (12.2 thousand ly) |
| Location | in the globular cluster M69(NGC6637) |
| Discovery | 2026 · misc |
| Source | ATNF Pulsar Catalogue |
| Right ascension (J2000) | 18h 30m 60.0s |
| Declination (J2000) | −32° 19′ 59″ |
In the sky
Visible from the whole Southern Hemisphere and north to latitude 58° N. South of latitude 58° 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 12 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 217 million years.