HELSINKI — China launched the latest in a series classified satellites into geosynchronous transfer orbit Sunday while disclosing little about the spacecraft. A Long March 3B rocket lifted off at 12:17 p.m. Eastern (1717 UTC) March 9 from the Xichang Satellite Launch Center, southwest China. The China Aerospace Science and Technology Corporation (CASC) announced launch success within an hour of liftoff. While the launch was anticipated due to airspace closure notices, the payload was unknown. CASC’s announcement revealed the mission payload to be communication technology experiment Satellite-15, or Tongxin Jishu Shiyan-15 (TJS-15). CASC provided only a brief description of the…