Galaxy · Spiral
IC 4644
IC 4644 is a galaxy in the direction of the constellation Apus, 228.7 million light-years away.
| Type | Spiral |
|---|---|
| Constellation | Apus |
| Distance | 228.7 million light-years (70.11 Mpc) |
| Diameter | 95,900 light-years · 1.1 × the Milky Way |
| Absolute magnitude | magnitude −20.74 |
| Apparent magnitude | magnitude 13.49 |
| Luminosity | 0.86 × the Milky Way |
| Right ascension (J2000) | 17h 24m 36.9s |
| Declination (J2000) | −73° 56′ 24″ |
| Source | 2MASS Redshift Survey (Huchra et al. 2012) |
In the sky
A telescope is needed to see it: its apparent magnitude is 13.49. Visible from the whole Southern Hemisphere and north to latitude 16° N. South of latitude 16° 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 229 million years ago. At that time dinosaurs ruled the Earth. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 4,056.4 billion years.