China’s attempt to launch its most powerful privately developed rocket failed on Friday after the vehicle suffered a flight anomaly. The Tianlong-3 rocket is being developed in hopes of breaking a key bottleneck in the country’s roll-out of internet satellite megaconstellations to compete with SpaceX’s Starlink. The Tianlong-3, built by Beijing-based start-up Space Pioneer and seen as China’s answer to the US company’s workhorse reusable Falcon 9, lifted off from the Jiuquan satellite launch...