Cosmic Scale
IC 1101
Supergiant elliptical galaxy · 1 billion light-years
How big is IC 1101?
IC 1101 is about 4 million light-years across.
See IC 1101 in 3D, at true scale
IC 1101 sits at the centre of a rich galaxy cluster and is one of the largest galaxies known. It is a supergiant elliptical: no spiral arms, little new star formation, just a vast swarm of ageing stars built up by swallowing smaller galaxies.
At a glance
| Diameter | 4 million light-years |
|---|---|
| Diameter compared with Earth | 3.0 × 10¹⁵ × Earth |
| Distance | About 1 billion light-years |
| Stars | Perhaps 100 trillion |
| Central black hole | Tens of billions of Suns |
| Discovered | 1790, William Herschel |
Good to know
- Its size is quoted anywhere from 600,000 to 4 million light-years, depending on where you decide its faint halo ends.
- Most of its stars are old and red; it has largely stopped making new ones.
- It grew by cannibalising other galaxies in its cluster over billions of years.
- Next smaller: ESO 383-76 · 1.8 million light-years
- Next larger: Local Group · 10 million light-years