The young cluster of super stars revealed in the latest Hubble image are called so because of their higher mass and much greater radiance, considering the fact that they are still young. Even though the star is thousand times younger, its luminosity suggests a much wider radius than the sun. 

According to a statement by NASA, this cluster, called Westerlund 1, is only 15,000 light years from Milky Way and at its edge lies the biggest star of the known universe, Westerlund 1-26. The statement also notes that the newly discovered star's radius is 1,500 times bigger than the sun.

The star, referred to as red hypergiant, is over 300,000 times more radiant than the sun. As for its size, if sun were to be replaced in the solar system by this star, it will range far beyond the orbit of Jupiter. In astronomical terms, the Westerlund 1 cluster is relatively young and most of its stars are known to have been formed 3 million years ago with similar compositions, making them much newer than the sun, Daily Magazine reported.

This massive cluster is a compact sized constellation first discovered in 1961. Scientists believe that due to presence of so many massive stars in Westerlund 1 cluster, it will end up being home to over thousand supernovae in a span of 40-million years. This cluster already contains several giant stars such as yellow supergiant and red hypergiant, including the newly discovered Westerlund 1-26.

Meanwhile, despite the sheer size of Westerlund 1-26, scientists reveal that it is not the largest star to be ever discovered. There are three more stars that are thought to be larger - UY Scuti which is located at 9,500 light years from Milky Way; RW Cephei about 11,500 light years away and WHO G64 thought to be positioned 168,000 light years away in the Large Magellanic Cloud. Among these three, UY Scuti is by far the largest known star.