Galaxy clusters are clusters of galaxies formed by a large number of galaxies under the constraint of gravity, generally containing hundreds to thousands of galaxies, like galactic cities in the universe. To better understand the formation and evolution of galaxy clusters, astronomers often look to the early universe in search of the prototypes of galaxy clusters, the so-called protoclusters.
In a new study, astronomers at the Canadian Astronomical Institute (IAC) used the Canary Large Telescope (GTC) to discover the densest and largest known protoclusters in the early universe.
Back in 2012, an international astronomical team accurately determined a galaxy in this area called HDF850.1, which is one of the highest rates of star formation in the observable universe and belongs to the rapidly developing protocluster. Surprisingly, they also found that HDF850.1 does not exist in isolation, with at least a dozen proto-galaxies clustered nearby.
Now, with the help of the Canary Telescope, astronomers at the Canadian Astronomical Institute have confirmed that this is one of the densestly distributed regions of early cosmic galaxies and have for the first time studied the physical properties of the system in detail.
Built on the island of La Palma in the Canary Islands, the Canary Large Telescope is the world's largest optical single-aperture reflecting telescope, with a maximum aperture of 10.4 meters and a concentrated area of 78.54 square meters, with a powerful deep space exploration capability in the universe.
The researchers found that this system is the largest known protocluster, with more than two dozen protoclusters. They speculate that over time, it will eventually evolve into a massive galaxy cluster, possibly on a scale comparable to the Virgo Cluster.
The Virgo Cluster is the central part of the Virgo Supercluster, containing more than 2500 galaxies, and the local galaxy group where our Milky Way is located is at best an inconspicuous blob next to it.
It should be noted that the light emitted by this protocluster traveled through the universe for 12.5 billion years before it was collected by the Large Canary Telescope, so what we see is actually what it looked like 12.5 billion years ago. At this moment, it is on the other side of the universe, like the Virgo cluster, has evolved into a mature galaxy cluster.
Researchers have published the findings in the Monthly Journal of the Royal Astronomical Society.
References:
https://phys.org/news/2021-02-grantecan-largest-cluster-galaxies-early.html