What is the most massive black hole?
The most massive black hole in this catalog is M87*, at about 6.5 billion times the mass of the Sun, the giant at the centre of the galaxy Messier 87. Everything about M87* →
| # | Black hole | Mass | Distance |
|---|---|---|---|
| ★ 1 | M87* | 6.5 billion suns | 54 million ly |
| 2 | Sombrero Central Black Hole | 1.0 billion suns | 30 million ly |
| 3 | M31* | 140 million suns | 2.5 million ly |
| 4 | Bode's Galaxy Central Black Hole | 70 million suns | 12 million ly |
| 5 | Centaurus A Central Black Hole | 55 million suns | 12 million ly |
| 6 | Messier 106 Central Black Hole | 39 million suns | 24 million ly |
| 7 | Sgr A* | 4 million suns | 26,000 ly |
| 8 | GW231123_135430 | 222 suns | 7.2 billion ly |
| 9 | GW190426_190642 | 173 suns | 14.9 billion ly |
| 10 | GW190521 | 147 suns | 10.8 billion ly |
| 11 | GW231028_153006 | 144 suns | 13.7 billion ly |
| 12 | GW200220_061928 | 141 suns | 19.6 billion ly |
| 13 | GW230704_212616 | 132 suns | 23.8 billion ly |
| 14 | GW231005_021030 | 127 suns | 20.5 billion ly |
| 15 | GW230922_040658 | 119 suns | 21.2 billion ly |
| 16 | GW241230_233618 | 112 suns | 8.8 billion ly |
| 17 | GW231001_140220 | 111 suns | 14.4 billion ly |
| 18 | GW190602_175927 | 111 suns | 9.3 billion ly |
| 19 | GW190706_222641 | 107 suns | 11.8 billion ly |
| 20 | GW191109_010717 | 107 suns | 4.2 billion ly |
| 21 | GW230814_061920 | 106 suns | 13.0 billion ly |
| 22 | GW240824_205609 | 103 suns | 17.3 billion ly |
| 23 | GW190403_051519 | 102 suns | 27.0 billion ly |
| 24 | GW230601_224134 | 102 suns | 12.1 billion ly |
| 25 | GW230819_171910 | 102 suns | 13.4 billion ly |
Showing the top 25 of 291 that qualify.
A supermassive black hole is weighed by watching what moves around it. Stars and gas near the centre of a galaxy orbit at speeds set entirely by the mass inside their orbit, so tracking them gives the mass without ever seeing the object itself. For the two black holes we have imaged, the size of the shadow provides a second, independent check, and the two agree.
Every mass in the top of this table belongs to a supermassive black hole at a galaxy's centre. The gravitational-wave detections lower down are a different animal entirely: stellar-mass holes of tens of suns, weighed from the shape of the spacetime ripple their merger sent out. The catalog holds both, and this ranking is dominated by the first kind for the obvious reason.
What is the most massive black hole?
The most massive black hole in this catalog is M87*, at about 6.5 billion times the mass of the Sun, the giant at the centre of the galaxy Messier 87.
How do you weigh a black hole you cannot see?
By its gravity. The orbital speed of stars and gas around a galaxy's centre depends only on the mass enclosed, so measuring those speeds weighs the black hole. For Messier 87 and Sagittarius A*, the Event Horizon Telescope added a direct check: the diameter of the shadow scales with mass.
How big is the most massive black hole?
M87* holds around 6.5 billion suns. An event horizon of that mass is wider than our entire solar system, which is what made the two largest ones possible to photograph at all.
How does it compare with the black hole in our own galaxy?
Sagittarius A*, at the centre of the Milky Way, is about 4.3 million solar masses: roughly a thousandth of the mass of the largest here. Both have been imaged by the Event Horizon Telescope.
Keep exploring: all records · every black hole we hold · the Milky Way's own black hole