(Source: CGTN)

China's first cargo spacecraft Tianzhou-1 is to be launched into space between April 20 and 24, according to the office of China's manned space program.

Photo taken on April 17, 2017 shows the cargo spacecraft Tianzhou-1 being transferred with a Long March-7 Y2 carrier rocket from the testing center to the launch zone in Wenchang, south China's Hainan Province. China's first cargo spacecraft Tianzhou-1 is to be launched into space between April 20 and 24, according to the office of China's manned space program. (Xinhua/Ju Zhenhua)

China's first cargo spacecraft, the Tianzhou-1 is vertically transported to the final launch pad on a Long March-7 rocket. Since the spacecraft arrived here in the middle of February, scientists and engineers have been assembling parts and conducting tests.

"It marks the completion of the assembly and testing in the technology area. Now in the launch area, we'll start working on the integration of gas, electricity and liquid and fuelling the rocket," Wang Ya, director of Wenchang Space Launch Center's Equipment Dept., said.

The Tianzhou-1 cargo ship will carry fuel and experiments to the space laboratory Tiangong-2.

The Long March-7 rocket carrying the Tianzhou-1 cargo spacecraft is now on this mobile platform, moving from the assembly building to the final launch pad. Moving such a massive object is no easy task, especially when it comes to the heaviest and biggest ever spacecraft in China.

"We have four big curved rails and the whole apparatus weighs over 1,800 tonnes, so transporting it has been a great challenge in terms of stability and safety. We practiced it a lot beforehand," Wu Yi, director of Wenchang Space Launch Center's Support System, said.

The Tianzhou-1 is bigger than any previous spacecraft made by China. With a net weight of 13 tons, it can carry a payload of up to 6.5 tons. If the launch is successful, China will have surpassed Europe and Japan in terms of cargo load ratio. When the rocket arrives at the launch pad, rotating platforms on the two sides of the tower will be swung around it to allow for fueling and final checks.

"Tianzhou-1 launch is the first field mission for the Long March-7 series of rockets. In the future, Tianzhou spacecrafts will act like deliverymen for our space station,"  Wang said.

The cargo spacecraft will be launched within the next few days. The Tianzhou-1 mission is an essential step in China's plan to establish a permanent space station around the year 2022.