Hubble Space Telescope uncovered a dwarf galaxy pair that came from the deep wilderness of the cosmos in an agglomeration of stars. Each of the tiny galaxies contains just 10 million stars.
The two small galaxies had been quiet for billions of years, and now they are strong enough to start giving birth to new stars.
The Hubble images captured the galaxies at a time when they were still passive. The researchers hope that, by studying the data, they will manage to get further insight on how dwarf galaxies are formed and how they transform over time.
Pisces A and Pisces B are two galaxies that spent their life in the Local Void, a region at 150 million light-years across that is hardly populated. However, the galactic big city used its gravity force to pull in the galaxy pair closer to the cluster.
While entering the crowded region, Pisces A and Pisces B would have plenty of intergalactic gas which they could use to create new stars.
Another theory is that the galaxy pair bumped into a gaseous filament which provoked the births of new stars by compressing the gas into their internal gravitational bounds.
Scientists believe that dwarf galaxies are the ancestors for larger galaxies such as our own. While the Local Void had stopped their evolution, approaching a busy galaxy cluster may offer astronomers a chance to study the way they create new stars and grow into different space formations.
The galaxy pair maintained their primitive composition, and they have a lower star density. They are compact and have higher concentrations of hydrogen.
The discovery was made while analyzing the hydrogen content in the Milky Way. The scientists identified up to 50 blobs of dense hydrogen gas, which they later monitored by using the WIYN telescope from Arizona. Out of these blobs, the images captured by Hubble confirmed the existence of the Pisces A and Pisces B galaxies.
Pisces A is located at 19 million light-years from Earth, and Pisces B is at 30 million light-years away. They both have up to 30 bright blue stars, which are very young.
The evolution of the galaxy pair puzzles scientists, as their star formation period was not constant. For example, 100 million years ago their birth rate doubled, but at this point, it is unclear what their path will be. Being close to a larger galaxy cluster may help them increase their rate, but if they become a satellite of a massive galaxy, then they may stop again from forming new stars.
The research team will continue to use Hubble to discover similar galaxies, which they will later confirm with the help of the Panoramic Survey Telescope and Rapid Response System survey.
Image Source: Wikipedia