Dark matter’s presence in the universe is one of the big mysteries. Most experts believe that it had a strong influence on the creation of the world, its structure as well as evolution. One of the theories states that the formation of some galaxies requires an abundant amount of invisible dark matter.
However, this theory may crumble as a team of astronomers from the Chinese Academy of Sciences in Beijing have new findings.
In their study, researchers have focused on the dark matter around the galaxies. They discovered 19 different galaxies that appear not to be surrounded by so much dark matter compared to the amount usually seen around the universe.
Researchers have been studying the galaxies ever since 2016, discovering that not all are rich in dark matter as previously theorized, or even lack it completely. These new findings raised the big question: Are galaxies formed of dark matter?
A galaxy lacking entierly of dark matter was discovered by Yale professor Pieter van Dokkum in 2018, giving the Beijing team the push to start their study.
How can galaxies form without dark matter?
Professor van Dokkum and his team have two theories. The first theory is about tidal stripping, which occurs when a more massive galaxy pulls stars and other stellar material from a smaller galaxy because of strong tidal forces.
Therefore it could remove the existing dark matter from the galaxy formed. The second theory is about the baryonic matter, or subatomic particles, in which a universe is created without the presence of the dark matter.
However, neither of the theories explain the lack of dark matter in the 19 galaxies found by the Chinese research team.
According to Ignacio Trujillo, a scientist who specializes in Extragalactic Astronomy at the Institute of Astrophysics of the Canary Islands, the chines research has a few issues. In regards to his opinion, researcher Jorge Sanchez Almeida, working alongside Trujillo, has argued that the calculations used for the 19 galaxies.
Dark matter remains one of the universe’s mysteries. However, once the technology advances, more questions will be answered regarding this subject.