China is gearing up to do something that could prove to be one of the biggest moments in the nation’s history. They are preparing to launch two astronauts on an expedition to the country’s new orbiting space lab module on Sunday for a full month. The Shenzhou 11 mission will feature commander Jing Haipeng and flight engineer Chen Dong, and they are set for liftoff from the Jiuquan space center at 2330 GMT (7:30 p.m. eastern time) on Sunday, and it will mark the sixth piloted spaceflight for the Chinese.

The capsule will be shot to space on a Long March 2F rocket. The launch will line up to when the orbital path of China’s Tiangong 2 space lab has passed over Jiuquan, which is situated in northwestern China near the Gobi desert. Automated docking should happened sometime on Tuesday, and then that will kick off a 30-day stretch aboard the module by Jing and Chen.

It’s the first time that China has sent a piloted craft into space for this long, being twice as long as the 14-day Shenzhou 10 mission back in June 2013.

It will be Jing’s third trip into orbit. He flew on the Shenzhou 7 and 9 missions, which took place in 2008 and 2012. He will be the first Chinese astronauts to go to space three times.

Chen is making his first trip into space.

The mission will involve experiments and technological demonstrations.