Cosmic Scale
TON 618
Ultramassive black hole · 10.4 billion light-years
How big is TON 618?
TON 618 is about 0.04 light-years across.
See TON 618 in 3D, at true scale
TON 618 is an ultramassive black hole powering a quasar so bright that we can see it from over ten billion light-years away. It was catalogued as a faint blue star in 1957 before anyone understood what quasars were.
At a glance
| Diameter | 0.04 light-years |
|---|---|
| Mass | 1.31 × 10⁴¹ kg |
| Diameter compared with Earth | 3.1 × 10⁷ × Earth |
| Distance | 10.4 billion light-years |
| Horizon | About 2,600 AU across |
| Luminosity | 140 trillion Suns |
Good to know
- Light takes about 15 days just to cross its event horizon.
- The quasar outshines its entire host galaxy by a factor of thousands.
- We see it as it was when the universe was about a quarter of its present age.
- Next smaller: Holmberg 15A* · 0.03 light-years
- Next larger: Phoenix A* · 0.06 light-years