Galaxy · Elliptical
And XXI
And XXI is a galaxy in the direction of the constellation Andromeda, 2.80 million light-years away.
| Type | Elliptical |
|---|---|
| Constellation | Andromeda |
| Distance | 2.80 million light-years (860.0 kpc) |
| Diameter | 5,023 light-years · 0.057 × the Milky Way |
| Absolute magnitude | magnitude −9.90 |
| Apparent magnitude | magnitude 14.77 |
| Luminosity | 4.0 × 10⁻⁵ × the Milky Way |
| Right ascension (J2000) | 23h 54m 47.7s |
| Declination (J2000) | +42° 28′ 15″ |
| Source | Updated Nearby Galaxy Catalog (Karachentsev et al. 2013) |
In the sky
A telescope is needed to see it: its apparent magnitude is 14.77. 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 September, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 2.8 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 49.8 billion years.