BEIJING, Oct 14, 2018 (BSS/XINHUA) – China plans to launch its first
satellite to test the technologies of the space-based gravitational wave
detection program “Tianqin” by the end of 2019.
The program Tianqin, meaning “harp in sky,” was initiated by Sun Yat-sen
University in south China’s Guangdong Province in 2015. It will consist of
three satellites forming an equilateral triangle around the earth.
“It’s like a harp in space. If the gravitational waves come, the ‘harp’s
strings” will be plucked,” said Luo Jun, president of the Sun Yat-sen
University and an academician of the Chinese Academy of Sciences, at a
conference held recently in Guangzhou, capital of Guangdong Province.
The detection will be based on high-precision laser interferometry
technology to measure the changes of the distances and locations of the three
satellites, 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, which are generated by the
merging of massive or supermassive black holes, scientists say.
The European Space Agency has also launched a space-based gravitational
wave detection program, the “Laser Interferometer Space Antenna” project.
Luo admitted that although China had achieved some breakthrough results in
the detection technology, there was still a huge gap to realize the space-
based detection of gravitational waves.
Laser-ranging is one of the necessary technologies for detection. China
accomplished its first successful laser-ranging between earth and the moon in
January this year.
The relay satellite of China’s Chang’e-4 lunar probe, launched in May this
year, carries a reflector developed by the Sun Yat-sen University, and is
expected to extend laser-ranging to a record distance of 460,000 km in 2019.
Scientists from Germany, Italy and Russia have expressed their willingness
to cooperate with China in gravitational wave detection.