TOKYO • Japan yesterday launched a space observation satellite tasked with studying mysterious black holes as Chinese scientists unveiled projects to investigate gravitational waves.

These developments followed the landmark discovery last week of gravitational waves in the United States. Black holes have never been directly observed, but the announcement of the first detection of gravitational waves indirectly added to the evidence that black holes do actually exist.

Japan's space agency said the ASTRO-H satellite, developed in collaboration between the agency, US space agency Nasa and other groups, is set to orbit at an altitude of about 580km and observe X-rays emanating mainly from black holes and galaxy clusters.

The satellite was carried into space by the H-IIA rocket, which was launched from the Tanegashima Space Centre in southern Japan yesterday. The Japan Aerospace Exploration Agency said the satellite separated from the rocket with no difficulty.

In Beijing, state media reported yesterday Chinese scientists will conduct three separate projects to investigate gravitational waves.

Space officials said such research would give China - which has a military-run, multibillion-dollar space programme that Beijing sees as symbolising the country's progress - an opportunity to become a "world leader" in the field.

The Chinese Academy of Sciences (CAS) rolled out a proposal for a space-based gravitational wave detection project, the official Xinhua news agency reported.

The proposed Taiji programme, named after the "supreme ultimate" of Chinese philosophy symbolised by the yin-yang sign, would send satellites of its own into orbit or share equipment with the European Space Agency's eLISA initiative.

"Gravitational waves provide us with a new tool to understand the universe, so China has to actively participate in the research," Mr Hu Wenrui, a prominent physicist in China and a member of the Chinese Academy of Sciences, told China Daily.

Separately, Sun Yat-sen University in Guangzhou also proposed to launch satellites into space to detect gravitational waves, while the Institute of High Energy Physics at CAS suggested a land-based scheme in Tibet.

Also in the news this week were reports of China moving more than 9,000 people in landlocked Guizhou province to make way for the world's largest radio telescope. The 500m Aperture Spherical Radio Telescope is due to start operation this year.

As well as upping investment in astronomy, Beijing is accelerating its multibillion-dollar space exploration programme, with plans for a permanent orbiting station by 2020 and eventually a manned mission to the moon.

AGENCE FRANCE-PRESSE