Leo I is one of a grouping of small galaxies that orb the Milky agency – but even among many , it is far from common . It appear that at the centre of this small-scale coltsfoot is a supermassive black hole comparable in mass to the Milky Way ’s own supermassive black hole , Sagittarius A * .
Sagittarius A * is judge to be 4.15 million times the mass of our Sun . surely a huge object , but tiny compared to the quite a little of the Milky Way , which is roughly one trillion solar lot . Leo I is a dwarf spheroidal galaxy much smaller than the Milky Way , and yet its supermassive black mess , as cover inThe Astrophysical Journal , appear to consider roughly 3 million time our Sun .
“ There is no explanation for this kind of black hole in dwarf spheroidal galaxies , ” lead source Dr María José Bustamante say in astatement .
The squad did not countersink out to measure a supermassive black pickle , and not one that could potentially be incredibly dense with respect to its host coltsfoot mass . Leo I has intrigue astronomers because it seems to own small dark matter , the hypothetical invisible substance that keeps galaxies in just shape . The team conduct elaborate notice of how the stars in this little galaxy move and try on to pattern the dark matter distribution – but the model enjoin a very different story .
“ The models are screaming that you need a black mess at the inwardness ; you do n’t really require a lot of dark thing , ” co - author Karl Gebhardt , from the University of Texas at Austin explained . “ You have a very small coltsfoot that is fall down into the Milky Way , and its black cakehole is about as massive as the Milky Way ’s . The mass ratio is absolutely huge . The milklike Way is dominant ; the Leo I ignominious hole is almost comparable . ”
While more observance will be needed to well understand this galaxy , the squad control this finding as an account for the ontogeny of supermassive contraband holes in monolithic galaxies . Galaxies grow and evolve through mergers , and so do their supermassive black holes . The mien of oversize supermassive black holes in lowly coltsfoot could excuse the tremendous sizing of supermassive pitch-dark holes in galaxies larger and heavier than the Milky Way .
“ If the mass of Leo I ’s bleak hole is high , that may explain how black holes grow in massive galaxies , " Gebhardt said . " That ’s because over time , as little galaxies like Leo I hang into larger galaxies , the little galaxy ’s dim hole merges with that of the larger galax , increasing its wad . ”
The team hopes to conduct observation of many other small galaxy around the Milky Way , studying their dark matter profile and supermassive fatal holes .
