The ‘chicken and egg’ question of whether a galaxy or its black hole comes first is one of the most debated subjects in astrophysics. A recent study suggested that supermassive black holes can trigger the formation of stars, thus ‘building’ their own host galaxies. This could be the long-sought missing link to understanding why the masses of black holes are larger in galaxies that contain more stars. To reach such an extraordinary conclusion, the team of astronomers conducted extensive observations of a peculiar object, the nearby quasar HE0450-2958, which is the only one for which a host galaxy has not yet been detected. HE0450-2958 is located some 5 billion light-years away.
This article describe about the result of the observations. These observations used a mid-infrared instrument on ESO’s Very Large Telescope. They discovered that an apparently unrelated galaxy in the quasar’s immediate neighbourhood is producing stars at a frantic rate. While no trace of stars is revealed around the black hole, its companion galaxy is extremely rich in bright and very young stars. The companion galaxy is, in fact, under fire: the quasar is spewing a jet of highly energetic particles towards its companion, accompanied by a stream of fast-moving gas. Galaxies would have evolved from clouds of gas hit by the energetic jets emerging from quasars. Although the quasar is still ‘naked’, it will eventually be ‘dressed’ when it merges with its star-rich companion. It will then finally reside inside a host galaxy like all other quasars.
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Source: ESO
