Astronomers working with the NASA’s Chandra X-Ray Observatory and ESA’s XMM-Newton have developed a technique to watch quasars and track the expansion of the Universe over the last 9 billion years. What they found is that the mysterious dark energy that’s currently accelerating the expansion of the Universe doesn’t appear to be a fixed amount. It’s changing, and appears to be increasing over time. If true, it’s a groundbreaking discovery in cosmology, and it could just fortel the end of the Universe.