China’s space agency says it has launched a spacecraft that promises to return samples from a pair of asteroids near Mars and yield “groundbreaking discoveries and expand humanity’s knowledge of the cosmos.” China National Space Administration says the Tianwen-2 probe launched early Thursday from southern China aboard the workhorse Long March 3-B rocket will collect samples from the near-Earth asteroid 2016HO3. The probe also will explore the main-belt comet 311P, which lies even further from the Earth than Mars. CNSA head Shan Zhongde says the Tianwen-2 mission represents a significant step in China’s journey of interplanetary exploration.