A team of astronomers mapping a group of 50 galaxies in the Milky Way’s neighborhood found a type of lonely dwarf galaxy 7 million light-years away that could give us some more hints about early Universe formation.
Astronomers have previously thought that the new found galaxy was attached to a larger galaxy located about 12 million light-years away. However, the dwarf galaxy was a stand-alone group, scientists said.
The findings were published in the astronomy journal Monthly Notices of the Royal Astronomical Society.
Researchers also said that the new findings may change their view on the evolution of cosmos since the group of 50 galaxies they were mapping was so densely populated.
“It may be that are a huge number of dwarf spheroidal galaxies out there, something that would have profound consequences for our ideas about the evolution of the cosmos,”
Dimitry Makarov, Russian researcher and a member of the team that discovered the new galaxy, said.
Scientists now say that small spheroidal galaxies such as KKs 3, the new found dwarf galaxy, are the forefathers of the larger and more massive galaxies such as the Milky Way. So, by understanding these galaxies we could find some detailed answers about early galaxy formation.
Additionally, KKs3 could also help astronomers understand more the distribution of dark matter across the universe since small galaxies are usually surrounded by a halo of dark matter.
Dwarf spheroidal galaxies are places where stars and planets are forming. Also, they are usually a satellite of a larger galaxy, rather than a stand-alone object such as KKs3.
Researchers say that dwarf spheroidal galaxies emerge after a gas-rich dwarf galaxy gets ‘captured’ by a larger galaxy that gradually empties if of gas and dust. But if a gas-rich ancient galaxy avoided being captured, it could self-consume its gas by producing stars. After all the gas was exhausted, the lonely dwarf galaxy turns into a spheroidal one such as KKs3.
The group of researchers that have discovered KKs3 used the Hubble Space Telescope to map the group of 50 galaxies located nearby the Milky Way. For the mapping, astronomers first detected the red giants within those galaxies. Red giants are dying stars that have almost exhausted all their hydrogen fuel.
Scientists also mapped KKs3 in August and found that its stars weight together 23 million times more than our sun. Also, it seems that this dwarf galaxy formed in the first 1.8 billion years after the universe emerged about 13.8 billion years ago.
KKs3 is not the only lone dwarf spheroidal galaxy astronomers have found. In 1999, researchers identified KKR25, a similar galaxy located 6 million light-years away.
Although this type of galaxies is hard to spot, astronomers hope that the new generation of space telescopes would make their task easier.
Image Source: Cosmos-Staruniverse