Black holes · Ultramassive black hole
Holmberg 15A*
700 million light-years · Light crosses it in 9.1 days
- Across
- 236.2 billion km
- Vs Earth
- 1,579 AU across
- Mass
- 40.0 billion Suns
Open Holmberg 15A* in Cosmic Scale
In the app, Holmberg 15A* is part of the Beyond pack.
About
Holmberg 15A is the brightest galaxy of its cluster, and its centre is strangely empty of stars — the signature of a huge black hole that scattered them away during past galaxy mergers. Its mass, measured directly in 2019, is around 40 billion Suns.
Sits at the centre of a galaxy with a strangely empty, star-poor core.
At a glance
| Distance | 700 million light-years |
|---|---|
| Black hole | About 40 billion Suns |
| Core | Depleted of stars |
| Measured | 2019 |
Did you know
- It is the most massive black hole measured directly from the motions of stars, rather than estimated indirectly.
- Its starved core spans thousands of light-years — bigger than the Large Magellanic Cloud.
- The galaxy is thought to have formed from the collision of two already-large ellipticals.