Source: //www.xinhuanet.com/english/2020-05/22/c_139076528.htm?from=groupmessage

GUANGZHOU, May 21 (Xinhua) -- Chinese space scientists and engineers have finished testing key technologies for space-based gravitational-wave detection with a dedicated satellite.

After the Tianqin-1 satellite was launched on Dec. 20, 2019, six key technologies have been tested over the past six months, including high-precision inertial sensing and micro-Newton propulsion, both of which are necessary to detect gravitational waves in space, said Luo Jun, president of Sun Yat-sen University and an academician of the Chinese Academy of Sciences.

"The test results are better than the mission requirements," Luo said on Thursday.

Tianqin-1 is the first technological experimental satellite of the Tianqin project, which started its systematic development from the university in south China's Guangdong Province in 2015. The project of Tianqin, meaning "harp in the sky," will consist of three satellites forming an equilateral triangle around the earth. When gravitational waves come, the "harp's strings will be plucked," according to Luo.

Gravitational waves are "ripples" in the fabric of space-time caused by some of the most violent and energetic processes in the universe. Albert Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity.

The first-ever discovery of gravitational waves by the American Laser Interferometer Gravitational-Wave Observatory (LIGO), announced in February 2016, has encouraged scientists worldwide to accelerate their research.

Different from LIGO, the space-based probes will be used to detect gravitational waves at much lower frequencies, such as those from the merging of massive black holes.