The James Webb Space Telescope continues to capture images of the universe that are clearer and more detailed than anything seen before. One of the latest images taken is of a “supercluster” called Westerlund 1, showing a rich collection of bright, jewel-like objects. A supercluster is a collection of young stars thousands of times larger than the Sun, all packed into a small area. Our galaxy used to produce more star clusters billions of years ago, but it doesn’t produce as many stars now, and the Milky Way still only has a few superclusters.
Westerland 1 is the largest existing supercluster in the galaxy and the closest star cluster to Earth. It is located 12,000 light-years away and consists of a massive star with a mass between 50,000 and 100,000 times that of the Sun within a 6-light-year diameter region. These stars include a yellow supergiant star that is about 1 million times brighter than the Sun. Because the stars in this cluster have relatively short lives, scientists believe the cluster is only about 3.5 million to 5 million years old. It’s quite young when you think about it on a cosmic scale. As such, it is a valuable source of data that can help us better understand how massive stars form and ultimately die. Although we can’t see it, this cluster is expected to produce 1,500 supernovae within 40 million years.
Astronomers took the images of the supercluster as part of an ongoing survey of other star clusters called Westerlund 1 and Westerlund 2 to study star formation and evolution. A Webb near-infrared camera (NIRCam) was used to capture this image. The camera was also recently used to image gravitational lensing supernovae, which could help us figure out how fast the universe is expanding.
