@space_telescopes

class="content__text" A spectacle of sparkling stars! Messier 92, number 92 in Charles Messier’s famous catalog of things that are not comets, is indeed not a comet. It’s a globular cluster—a giant ball of stars 27,000 light-years away in the constellation Hercules. This detail of an image captured by the James Webb Space Telescope’s Near-Infrared Camera (NIRCam) shows a small portion of the cluster, which is one of the oldest—if not the oldest—globular clusters in the Milky Way. Because all of its stars formed around the same time, somewhere between 12 and 13 billion years ago, astronomers can use M92 to better understand how stars of different masses evolve as well as what the ancient universe was like. Like other globular clusters, the stars in M92 are packed extremely tightly. Adjacent stars are so close together—just fractions of one light-year apart—that the night sky of a potential planet in the cluster’s core (outside this field of view toward the upper left) would be very bright. It would shine with thousands of stars that appear thousands of times brighter than those in our own sky. Astronomers are using Webb’s observation of M92 to improve tools and methods for studying stars that are close together on the sky. Credit: NASA, ESA, CSA, A. Pagan (STScI). ALT TEXT: Square filled with blue, white, yellow, and red points of light of different sizes and brightnesses, most of which are stars. The larger and brighter stars show Webb’s distinctive diffraction pattern consisting of eight spikes radiating from the center. At the lower right is a scale bar labeled 2 light-years. The scale bar is two-ninths the width of the image, and shows that throughout the image, the distance between adjacent stars is a fraction of one light-year. The density of stars and brightness of the image is greatest in the upper left portion of the image, where the stars are much closer together, and decreases gradually toward the bottom right, where they are farther apart. The number of larger, brighter stars also appears to decrease from the upper left toward the lower right.

February 23, 2023