Galaxy · Spiral
NGC 891
NGC 891 is a galaxy in the direction of the constellation Andromeda, 29.7 million light-years away. An edge-on spiral that closely resembles the Milky Way.
| Type | Spiral |
|---|---|
| Constellation | Andromeda |
| Distance | 29.7 million light-years (9.10 Mpc) |
| Diameter | 107,600 light-years · 1.2 × the Milky Way |
| Absolute magnitude | magnitude −20.90 |
| Apparent magnitude | magnitude 8.90 |
| Luminosity | 1 × the Milky Way |
| Right ascension (J2000) | 2h 22m 33.4s |
| Declination (J2000) | +42° 20′ 56″ |
| Source | Compiled catalogue (NED, approximate values) |
In the sky
Too faint for the naked eye (magnitude 8.90); binoculars will find it. Visible from the whole Northern Hemisphere and south to latitude 48° S. North of latitude 48° N it never sets. It stands highest at midnight in October, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 30 million years ago. At that time the dinosaurs were gone and mammals were diversifying; there was no human lineage yet. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 526.5 billion years.