Photo shows a scale model of the Mars rover and lander.Photo: clep.org.cn

China's first Mars probe, named Tianwen-1, has arrived at the Wenchang Spacecraft Launch Center in South China's Hainan Province, according to the spacecraft developer on Tuesday.

The announcement was made by the China Academy of Space Technology under the state-owned space giant China Aerospace Science and Technology Corp (CASC), the contractor. Pre-launch preparations are in progress, China News Service reported.

China's space authorities have yet to announce a launch date. But China's third-generation space tracking ship Yuanwang-6 set sail on Monday to conduct maritime spacecraft monitoring and control missions in the Pacific, Indian and Atlantic oceans. 

According to sources close to China's space system, it's the first time a Yuanwang vessel will perform a mission in these three oceans in a single journey, prompting great anticipation for China's first Mars probe.

The launch window has been set between July and August, according to previous reports. 

The vessel returned to its home port in East China's Jiangsu Province after completing the monitoring and control mission for the 55th satellite of China's domestic BeiDou Navigation Satellite System on July 3. After nine days of preparation, the vessel set sail again for new missions, sources told the Global Times on Tuesday. 

Luo Haiting, director of the human resources department of the Yuanwang-6, was quoted by the Beijing-based China Youth Daily in early July as saying that the vessel would set sail for multiple missions, including the one for the Mars probe. The new missions would involve more than 110 days at sea.

The deployment of the space tracking vessel could indicate that the Mars mission is technically ready and may occur soon. The mission requires a longer period of monitoring and control, as indicated by the Yuanwang-6 travel plan, Song Zhongping, a military and space technology expert, told the Global Times.  

Bao Weimin, an academician from the Chinese Academy of Sciences and director of the Science and Technology Commission of CASC, revealed in June, the Long March-5, which is currently China's largest and strongest carrier rocket, will carry out the launch.

China aims to achieve orbiting, landing and roving Mars all in one mission. It will also eventually attempt a sample-return mission on the red planet, according to an article released on Space Day of China's official WeChat account on Monday.

China successfully conducted a Mars landing test of the country's Red Planet lander in North China's Hebei Province in November 2019.

The launch window for Mars exploration this year opens between July and August, and China's Tianwen-1 is one of the remaining three projects. ExoMars, a cooperation program between Europe and Russia, earlier announced that it will be delayed to 2022.

The other two Mars missions left are the Mars 2020 of the US and the Hope Mars Mission of the United Arab Emirates (UAE), which are also scheduled for this month.

NASA moved its first launch attempt of the Mars 2020 mission to no earlier than July 30, according to the US space agency's official website.

A liquid oxygen sensor line presented off-nominal data during the Wet Dress Rehearsal, and additional time is needed for the team to inspect and evaluate, NASA explained. 

The UAE will only launch an orbiter. The Hope Probe - the first interplanetary mission for an Arab country - is scheduled to blast off on Wednesday morning, CGTN reported.