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Satellite used by Defense Ministry to monitor Japan breaks down

The front gate to the Defense Ministry is seen in Tokyo's Shinjuku Ward on March 16, 2019. (Mainichi/Kazuo Motohashi)

TOKYO -- A commercial imaging satellite, which the Defense Ministry had top priority in using, has broken down, causing flaws to its surveillance network around Japan, those linked to the government said.

The ministry is making up for the flaws by using information-gathering satellites operated by the Cabinet Satellite Intelligence Center and other satellites. However, the trouble with the imaging satellite, "WorldView-4" that is operated by U.S. satellite imaging giant DigitalGlobe, has adversely affected operations of the network and caused the quality of images to decline.

The Defense Ministry is poised to look for a substitute satellite over which it can have the right for priority use as North Korea is intensifying its military activities, such as the launch of short-range ballistic missiles.

The ministry does not possess information-gathering satellites but operates two X-band communications satellites.

The Cabinet Satellite Intelligence Center owns two information-gathering satellites equipped with optical cameras. These cameras have the capacity to photograph certain locations on the ground at least once a day. However, since these satellites are used for many other purposes, including responding to natural disasters, the Defense Ministry has bought photos taken by the commercial satellite.

WorldView-4 is one of the most advanced optical satellites capable of identifying objects as small as about 30 centimeters from an altitude of approximately 600 kilometers. The ministry obtained the highest priority in using the satellite shortly after it was launched in November 2016.

Since then, the ministry has renewed its contract with DigitalGlobe every year for priority use of WorldView, and paid some 8 billion yen to the company a year, using the satellite to analyze North Korea's nuclear facilities and ballistic missiles and monitor China and Russia's military trends.

However, Maxar Technologies Ltd., the parent company of DigitalGlobe, announced in January 2019 that WorldView-4's attitude-control system developed trouble and that there was a high possibility that it could not be repaired.

The Defense Ministry canceled its contract with DigitalGlobe for the use of WorldView-4 from February onward because it became unable to obtain images from the satellite. The ministry currently uses images from information-gathering satellites operated by the Cabinet Satellite Intelligence Center as well as other commercial satellites.

The ministry claims that the trouble has not dealt a fatal blow to its information-gathering activities.

However, an individual linked to the government pointed out that the trouble has made it difficult for the ministry to flexibly gather necessary information. "The time when information-gathering satellites can be used for our activities is limited. Such satellites play other roles such as responding to natural disasters. It's difficult to gather necessary information on specific locations at specific times from other commercial satellites that the ministry doesn't have priority in using," the source said.

The United States already has first choice in using another DigitalGlobe satellite with capabilities similar to those of WorldView-4. The ministry intends to acquire the right for priority use of another satellite. However, the ministry is struggling to select satellites because other entities have contracts to use them.

(Japanese original by Shinichi Akiyama, Political News Department)

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