Watch NASA’s STP-2 technology briefing

Nine Merlin engines ignited and throttled up to nearly 2 million pounds of thrust Sunday during a brief hold-down firing of SpaceX’s Falcon 9 rocket, sending a plume of smoke out of the flame trench at Kennedy Space Center’s historic launch pad 39A as the company preps for a space station cargo mission next weekend.

SpaceX started the week with the launch of a Falcon 9 rocket from NASA’s Kennedy Space Center in Florida just after sunrise Monday, delivering a classified U.S. government spy satellite to orbit as the booster’s first stage returned to Cape Canaveral for a vertical landing.

China launched the third in a series of experimental Shiyan 6 satellites April 8 aboard a Long March 4B rocket, beginning a mission to test new space technologies, including a new super-black coating to absorb stray light and improve the sensitivity of on-board optics.