Black Hole Binary
Short answer: A supermassive black hole binary forms after two galaxies merge and their central black holes sink toward the middle and orbit each other.
They spiral closer through interactions with surrounding stars and gas and, finally, by emitting gravitational waves, before merging into one more massive black hole. The footage, credited to astropodis, shows a simulation of two black holes orbiting.
What should you know about Black Hole Binary?
Quick facts. Each one stands alone and has a stable ID you can cite.
Galaxy mergers.
Two black holes.
Video transcript: Black Hole Binary: When Galaxies Collide, Their Central Black Holes Can End up Orbiting Each Other
Did you know, binary supermassive black hole systems consist of two supermassive black holes orbiting each other, typically found at the centers of merging galaxies. These systems form when two galaxies collide, bringing their central black holes into close proximity, as the black holes spiral closer due to gravitational interactions, and the loss of energy through the emission of gravitational waves, they eventually merge into a single, even more massive black hole. NOW YOU KNOW!
Burned-in captions, read frame by frame (see transcript.md) · 23.0s Reel ·
The write-up
When galaxies collide, their central black holes can end up orbiting each other. Gravitational waves drain their energy until they merge.
- Exhibit A
Origin
Galaxy mergers.
- Exhibit B
Orbit
Two black holes.
- Exhibit C
Inspiral
Energy lost.
- Exhibit D
Waves
Gravitational waves.
- Exhibit E
End
One larger black hole.
Questions people ask about Black Hole Binary
What forms them?
Collisions.
Source: Write-up · Exhibit A (Origin) · Wikipedia: Binary black hole
What carries energy away?
Ripples.
Source: Write-up · Exhibit B (Orbit) · Wikipedia: Binary black hole
End result?
Merger.
Source: Write-up · Exhibit C (Inspiral) · Wikipedia: Binary black hole
Where found?
Cores.
Source: Write-up · Exhibit D (Waves) · Wikipedia: Binary black hole
What do they do first?
Binary.
Source: Write-up · Exhibit E (End) · Wikipedia: Binary black hole
Test Your Knowledge
All quizzes →5 questions, all from this case file. Answers are revealed instantly.
What forms them?
- Galaxy mergers
- Supernovas
- Comets
- Planets
Show the answer
Answer: A. Galaxy mergers Collisions. Source: Write-up · Exhibit A (Origin) · Wikipedia: Binary black hole
What carries energy away?
- Gravitational waves
- Light only
- Sound
- Wind
Show the answer
Answer: A. Gravitational waves Ripples. Source: Write-up · Exhibit B (Orbit) · Wikipedia: Binary black hole
End result?
- One larger black hole
- Two stars
- Nothing
- A galaxy split
Show the answer
Answer: A. One larger black hole Merger. Source: Write-up · Exhibit C (Inspiral) · Wikipedia: Binary black hole
Where found?
- Galaxy centers
- Near Earth
- Inside the Sun
- In comets
Show the answer
Answer: A. Galaxy centers Cores. Source: Write-up · Exhibit D (Waves) · Wikipedia: Binary black hole
What do they do first?
- Orbit each other
- Explode
- Shrink
- Freeze
Show the answer
Answer: A. Orbit each other Binary. Source: Write-up · Exhibit E (End) · Wikipedia: Binary black hole
Cite this case file
Easterling, Marcus. "Black Hole Binary." The Detail Department (DetailEnjoyer), case file DD-464, last updated Jan 20, 2025. https://detailenjoyer.com/case/black-hole-binary/
Permalink: https://detailenjoyer.com/case/black-hole-binary/ · Last updated
Cite a single fact by its ID, for example DD-464-F01 → https://detailenjoyer.com/case/black-hole-binary/#DD-464-F01
