- #1
snorkack
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- TL;DR Summary
- How powerful is a galactic nucleus to be called "active"? "quasar"?
Milky Way centre cannot be seen because of Great Rift, but it is known as a loud radio source Sagittarius A since 1930s.
What would be the absolute magnitude of Sagittarius A if it could be seen? Visual magnitude?
Not all galaxies have loud centres. Large Magellanic Cloud does not show a sign of a powerful point radio source. Neither does Triangulum.
Yet despite Sgr A being one of the loudest radio objects in sky, Milky Way is not regarded as a radio galaxy, nor a Seyfert galaxy.
What is the magnitude threshold above which a galactic nucleus is classified as active and below which, passive?
Also, what is the magnitude threshold above which a galactic nucleus is a quasar and below which, a Seyfert galaxy?
What would be the absolute magnitude of Sagittarius A if it could be seen? Visual magnitude?
Not all galaxies have loud centres. Large Magellanic Cloud does not show a sign of a powerful point radio source. Neither does Triangulum.
Yet despite Sgr A being one of the loudest radio objects in sky, Milky Way is not regarded as a radio galaxy, nor a Seyfert galaxy.
What is the magnitude threshold above which a galactic nucleus is classified as active and below which, passive?
Also, what is the magnitude threshold above which a galactic nucleus is a quasar and below which, a Seyfert galaxy?