NGC 6540 is a globular cluster in the constellation Sagittarius, about 17,000 light years away from Earth. NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 and Advanced Camera for Surveys recently captured a dazzling image of the globular cluster NGC 6540, showing the star-studded area of the sky.
The globular cluster NGC 6540 is a stable, tightly bound multitude of stars. These clusters can contain tens of thousands to millions of stars, all brought together by gravitational attraction and kept close to one another.
To assist astronomers in determining the ages, shapes, and structures of globular clusters closer to the Milky Way’s center, Hubble gazed into the center of NGC 6540. Some of the light from these clusters is blocked by the gas and dust that surrounds the galactic center of our galaxy, which also gradually alters the color of their stars. Globular clusters provide information about the Milky Way’s early history, so astronomers can learn more about the evolution of our galaxy by studying them.
NASA officials wrote in a statement, “The brightest stars in this image are adorned with prominent cross-shaped patterns of light known as diffraction spikes. These astronomical embellishments are a type of imaging artifact, meaning that they are caused by the structure of Hubble rather than the stars themselves. The path taken by the starlight as it enters the telescope is slightly disturbed by its internal structure, causing bright objects to be surrounded by spikes of light.”