Active galactic nucleus common observation characteristics
The common observation features are:
1. Bright and dense nuclear area;
2. The spectrum has a high red shift, indicating that the distance is far on the cosmological scale, and the luminosity is very high, which is much higher than that of ordinary galaxies.
3. It has rapid light change, and the time scale of light change varies from hours to days, showing that its scale only occupies a small part of the entire galaxy.
4. There is a very broad emission line in the spectrum;
5. With non-thermal radiation spectrum;
6. Jet phenomenon with optical or radio