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 water measured in the quasar is in the form of vapor and is the largest mass of water ever found, according to the researchers. The amount of water estimated to be in the quasar is at least 100,000 times the mass of the sun, equivalent to 34 billion times the mass of the Earth.