BEIJING (AP) — China has landed a spacecraft on Mars for the first time in the latest step forward for its ambitious space program. Plans call for a rover to stay in the lander for a few days of diagnostic tests before rolling down a ramp to explore an area of Mars known as Utopia Planitia. It will join an American rover that arrived at the red planet in February. China’s first Mars landing follows its launch last month of the main section of what will be a permanent space station and a mission that brought back rocks from the moon. Announcing the landing Saturday, the official Xinhua News Agency says China has left a footprint on Mars, an important step for the country’s space exploration.