|Work for an intelligence-gathering system began after North Korea launched a missile over Japan in 1998 [Reuters]
Japan has launched a new spy satellite into orbit amid concerns over North Korea's missile programme and to monitor natural disasters in the region, officials said.
The Japanese H-2A rocket, carrying an information-gathering radar satellite, lifted off at 0121 GMT on Monday from the Tanegashima Space Centre in southwestern Japan.
"The rocket was launched successfully," said Toshiyuki Miura, a spokesman for Mitsubishi Heavy Industries (MHI), which built the satellite and worked on the launch with the Japan Aerospace Exploration Agency (JAXA).
"The satellite was separated into orbit around the Earth later."
The government decided to build an intelligence-gathering system after North Korea launched a missile in 1998 that flew over the Japanese archipelago and into the Pacific, shocking many in Japan.
In defiance of international pressure, North Korea then launched what was believed to be a three-stage Taepodong-2 missile in April 2009, with an estimated range of 6,700Km.
Japan has three operating optical satellites. Two radar ones were successfully placed into orbit, but both broke down later. Another optical satellite was launched in September, but is not yet functioning.
Demand for land surveillance grew meanwhile after Japan's March 11 earthquake and tsunami, which killed about 20,000 people and crippled cooling systems at the Fukushima Daiichi nuclear plant, northeast of Tokyo, causing reactor meltdowns.
"The project is aimed at boosting security and monitoring land in case of sizable natural disasters like the one in March," a government official said, adding that the current three satellites were used to track the March calamity.
"If everything goes smoothly, it will be the first radar satellite under the programme," the official said. "With the radar satellite, we can introduce wider usage of the system."
Radar satellites are able to capture images at night and in cloudy weather, something that optical satellites cannot.
The latest satellite cost about $512m to develop, Kyodo News reported.
JAXA and MHI had originally planned to launch the satellite on December 11, but it was postponed due to bad weather.