Glittering Sky

Credit: NASA & ESA

A glit­ter­ing sky of lights greets us in this NASA Hub­ble Space Tele­scope image of the glob­u­lar clus­ter Omega Cen­tauri. This image shows just a small part of the mas­sive star clus­ter with 10 mil­lion suns. Glob­u­lar star clus­ters are groups of mil­lions of stars bound together by grav­ity. Omega Cen­tauri is very old too. Stars in this clus­ter were among the first stars to form in the Milky Way Galaxy more than 10 bil­lion years ago. By con­trast, our Sun arrived on the scene only 4.6 bil­lion years ago.

This image of Omega Cen­tauri con­tains stars of every age. Explore the image. What col­ors of stars can you find?

Most are yellow-white stars like our Sun. Some have reached the end of their life and have become red giants. While other stars shine with a blue light, either because they are new or they have become what is known as blue strag­glers. Blue strag­glers have gained a new life by col­lid­ing with other stars. This new fuel helps the star burn hot­ter and bluer. Stars in this clus­ter are cozy sep­a­rated by about one-third of a light-year. This is much closer than the Sun is to its near­est starry neigh­bor, Prox­ima Centauri.