Astronomers have discovered that the Milky Way galaxy's spiral arms extend significantly farther and wider than previously estimated. Using data from NASA's Chandra X-ray observatory and the ESA's XMM-Newton observatory, researchers measured X-ray light from distant gamma-ray bursts as it scattered off dust clouds within our galaxy's arms. This geometric method allowed lead author Beatrice Vaia and her team to determine that the Outer and Outer-Scutum-Centaurus arms are approximately ten percent more distant than once thought. Additionally, the team measured the most distant arm's thickness at roughly 3,500 light-years. These findings, published in Astronomy & Astrophysics, suggest that scientists may need to revise fundamental understandings regarding the galaxy's total mass distribution, rotation, and overall structural evolution. Because gamma-ray bursts are rare, these precise measurements rely on infrequent cosmic events to provide accurate galactic dimensions.