Gravity wave detector test begins

A Japanese team of scientists are attempting to detect so-called gravitational waves, space-time ripples first theorised by Albert Einstein 100 years ago.

Japanese scientists have begun a test run of underground telescope KAGRA to detect gravitational waves and gain a better understanding of the universe through their observations, Japan's Kyodo agency reports.

The test run, which began on Friday and will continue until Thursday, comes a month after a US-led team of scientists said they had identified the gravitational waves, theorised 100 years ago by Albert Einstein.

The KAGRA telescope is installed inside an L-shaped tunnel with each arm extending 3km and located more than 200m underground at the Kamioka mine site in the central Gifu prefecture to minimise seismic noise.

The facility uses laser beams moving back and forth inside vacuum pipes that have mirrors placed at each end to detect the very small waves.

The Japanese efforts to detect gravitational waves are led by 2015 Physics Nobel laureate Takaaki Kajita from the University of Tokyo.

After checking the telescope's performance with another test run in April, the Japanese team plans to make modifications to boost its sensitivity and start full-fledged operation between 2017 and 2018.

"We want to join the international network of gravitational wave observation as soon as possible," Kajita said in a statement.

Gravitational waves GW150914 were discovered on September 14, 2015, by twin Laser Interferometer Gravitational-wave Observatory (LIGO) detectors in the USA's Livingston, Louisiana, and Hanford, Washington.