Black-hole process
Quasi-Periodic Oscillation
A near-regular flickering in the X-ray brightness of matter orbiting a black hole or neutron star, revealed in the power spectrum as a broad peak rather than a sharp tone. QPOs probe the innermost accretion flow, close to the innermost stable circular orbit, and are used to study strong gravity — though their exact origin is still debated.
Highlights
- ›X-ray flickering that probes the inner accretion flow
Classes, physics & objects
Knowledge connections
- Associated withBlack Hole
- Associated withAccretion Disk
- Associated withThe Innermost Stable Circular Orbit
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.