Researchers using data provided by the Dark Energy Survey have discovered nine possible dwarf galaxies that are orbiting our own Milky Way, according to a study published online on Tuesday.
Three of these can already be classified as tiny galaxies, with the rest being deemed as satellites orbiting the Milky Way until further research. They were observed along the southern sky, near the Large and Small Magellan clouds – the largest satellite galaxies that orbit our star system.
They were discovered by a joint American-British team working with data from the Dark Energy Survey, a multinational project that aims to map out vast portions of the southern sky until 2018. The ultimate stated aim of the project, that has its headquarters at the Fermi National Accelerator Laboratory, is to understand the nature of the accelerating expansion of the Universe and the dark energy that fuels it.
The dwarf clusters were observed from data gathered with a 570-megapixel camera named the DECam, used in conjunction with a Blanco telescope from the Cerro Tololo Inter-American Observatory. This is the first time since 2006 that satellite galaxies orbiting the Milky Way have been observed, and also represents the largest batch of such galaxies ever discovered in one study.
Dwarf galaxies are smaller clusters composed of as few as a couple of hundreds of stars, opposed to the billions that normal galaxies such are com. These smaller galaxies usually are in orbit of bigger galaxies due to the gravitational pull they provide. The low number of stars they harbor make them extremely obscure and tough to be observed, which the reason for which only a couple of dozens of such entities have been discovered until now.
It is thought that these smaller star systems may have once been satellites to the Large and Small Magellanic clouds, but that they were thrown off-path by interaction between the two and caught in our galaxy’s orbit. Their distance from the Earth varies between 97,000 and more than 1.2 million light years.
The ultimate importance regarding the study of dwarf galaxies is that their mass is mostly formed out of dark matter rather than stars as most other clusters, which could prove an ideal study ground to find out more about elusive substance that comprises more than 84% of the known universe.
Image Source: Discovery
