中国“天问一号”火星探测器发射 - 2020年07月24日

Never have interplanetary flights to Mars been on such a busy schedule, with three international probes to the planet leaving within days of each other.
The United Arab Emirates' Hope orbiter blasted off aboard a rocket on Monday in Japan, becoming the first of three probes headed to Mars this summer. On Thursday, China launched its Tianwen-1 probe, aiming to complete orbiting, landing and roving in one mission. The US will launch its Mars 2020 probe in tow with the liftoff of the Perseverance rover.
The probes are launched in quick succession due to the occurrence of a biennial launch window, the optimal period for spacecraft to fly to Mars.