Star cluster
NGC 6633
Open star cluster · 575 million years
An open cluster of stars born together from the same gas cloud in the Milky Way’s disc; the Galaxy’s tidal forces will disperse it within a few hundred million years. Position, distance, age and member count come from the MWSC catalogue; the total brightness is roughly estimated from the member count.
| Type | Star cluster |
|---|---|
| Constellation | Ophiuchus |
| Distance | 385 pc (1.3 thousand ly) |
| Age | 575 million years |
| Member stars (MWSC) | 145 |
| Reddening E(B−V) | 0.18 |
| Metallicity [Fe/H] | 0.06 |
| Source | MWSC (Kharchenko et al. 2013) |
| Right ascension (J2000) | 18h 27m 20.5s |
| Declination (J2000) | +6° 30′ 00″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 83° 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 around the year 770. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 22 million years.