Cistus, with its many hybrids and cultivars, is commonly encountered as a garden flower. The common name rockrose is applied to the species, a name also shared by the related genera Halimium, Helianthemum and Tuberaria, all in the family Cistaceae. The common name gum cistus is applied to resin-bearing species, especially C. ladanifer.
Quasars are part of a class of objects known as active galactic nuclei (AGN). Other classes include Seyfert galaxies and blazars. All three require supermassive black holes to power them.
The currently brightest known quasar is the ultraluminous 3C 273 in the constellation of Virgo. It has an average apparent magnitude of 12.8 (when observing with a telescope), but it has an absolute magnitude of â26.7. So from a distance of 10 parsecs, this object would shine in the sky about as bright as our sun.he currently brightest known quasar is the ultraluminous 3C 273 in the constellation of Virgo. It has an average apparent magnitude of 12.8 (when observing with a telescope), but it has an absolute magnitude of â26.7. So from a distance of 10 parsecs, this object would shine in the sky about as bright as our sun.