The launch of NASA’s twin GRAIL spacecraft

Flying for the 155th and final time, a United Launch Alliance Delta 2 rocket took off from California on Sept. 15 with NASA’s ICESat 2 satellite.

The next American polar-orbiting weather satellite that will feed long-range forecasts and track environmental trends has slipped into space-like testing ahead of launch.

The next-to-last Delta 2 rocket is being stacked at its California launch site to take flight in January to put a civilian weather satellite into polar orbit.