This April, the 13-ton Tianzhou-1 spacecraft will be brought to space by a Long March-7 rocket from the Wenchang launch site in northeast China. It will dock with the Tiangong-2 space lab 390 kilometers above earth.

The mission's main objective is to test the transfer of liquid propellant to the Tiangong-2 lab in orbit. The lab was launched last year and hosted two Chinese astronauts for a month, the country's longest-ever manned mission.  

"Two days after the launch of Tianzhou-1, it will dock with the Tiangong-2 space lab. The whole process takes about two months. After the completion of the two-month docking, we will check the status of the equipment and refill the propellant." said Bai Mingsheng, Tianzhou-1 Chief designer of China Aerospace Science and Technology Corporation.

Tianzhou-1 is nine meters long and over three meters wide. It can carry 65-hundred kilograms of cargo, and was designed specifically for refuel and resupply missions for a space station China intends to send into orbit by 2018.

"For example the daily supplies of the astronauts, including food and clothing, extravehicular space suits, as well as drinking water with special tanks. We will see if the Tianzhou-1 spacecraft meets the demand of transporting and resupplying various goods through this launch." said Bai

Tianzhou-1's success will be crucial to China's aspiration of having permanent human presence in space. The Chinese space station is planned to be completed by 2022.