Galaxy · Spiral
NGC 4639
NGC 4639 is a galaxy in the direction of the constellation Virgo, 52.0 million light-years away.
| Type | Spiral |
|---|---|
| Constellation | Virgo |
| Distance | 52.0 million light-years (15.95 Mpc) |
| Diameter | 43,900 light-years · 0.5 × the Milky Way |
| Absolute magnitude | magnitude −19.38 |
| Apparent magnitude | magnitude 11.63 |
| Luminosity | 0.25 × the Milky Way |
| Right ascension (J2000) | 12h 42m 52.4s |
| Declination (J2000) | +13° 15′ 26″ |
| Source | 2MASS Redshift Survey (Huchra et al. 2012) |
In the sky
A telescope is needed to see it: its apparent magnitude is 11.63. Visible from the whole Northern Hemisphere and south to latitude 77° S. North of latitude 77° N it never sets. It stands highest at midnight in March, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out 52 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 922.8 billion years.