Star cluster
IC 2157
Open star cluster · 79 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 | Gemini |
| Distance | 2,311 pc (7.5 thousand ly) |
| Age | 79 million years |
| Member stars (MWSC) | 92 |
| Reddening E(B−V) | 0.56 |
| Source | MWSC (Kharchenko et al. 2013) |
| Right ascension (J2000) | 6h 04m 49.8s |
| Declination (J2000) | +24° 04′ 12″ |
In the sky
Visible from the whole Northern Hemisphere and south to latitude 66° S. North of latitude 66° N it never sets. It stands highest at midnight in December, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 7,538 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 134 million years.