Sci-tech Advances
China announces new gravitational wave observation

Chinese scientists on Monday announced observation of the "optical counterpart" of gravitational waves coming from the merger of two binary neutron stars using a survey telescope in Antarctica.

The gravitational waves were first discovered by the U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors on Aug. 17. The Chinese telescope independently observed optical signals resulting from the merger the next day, according to the Chinese Center for Antarctic Astronomy.

It was the first time humans have detected gravitational waves and the corresponding electromagnetic phenomena resulting from a binary neutron star merger.

Data exclusively collected by the Chinese detector has led to a preliminary estimate of the ejecta parameters, according to Wang Lifan, director of the center.

The merging process ejected radioactive material with more than 3,000 times the mass of the Earth at a speed of up to 30 percent the speed of light, Wang said.

The host galaxy of the incident is located about 130 million light years from the Earth.

In 2015, LIGO detectors confirmed the existence of gravitational waves produced during the merger of two black holes, which were predicted by Albert Einstein's theory of general relativity 100 years ago.

So far, LIGO and its partners have discovered four cases of gravitational waves coming from mergers of two black holes.

The Chinese telescope is a catadioptric optical telescope with an entrance pupil diameter of 500 mm. Its unique location allows for continuous observations lasting longer than 24 hours during the austral winter.

(From Xinhua, October 16, 2017)