Japan's military could be extending its reach into space, with the country planning to develop a new force by 2019 to monitor the growing amount of space junk in orbit.

The initiative, which aims to protect satellites from being damaged by orbital debris, is also designed to boost cooperation in space between Japan and the United States, reported AFP. Both countries have emphasized the need to address the troubling cloud of debris in low-Earth orbit, with unnamed Japanese sources calling space the "fourth battlefield," according to the Tokyo-based Kyodo news agency.

Millions of pieces of man-made debris crowd a region of low-Earth orbit high above the planet's atmosphere. These pieces of space junk range from spent rocket bodies to discarded nuts and bolts to tiny flecks of paint. Left unmonitored, these bits of space trash could collide with satellites and other spacecraft, including the International Space Station.

Japan's new space military division will likely be an offshoot of the country's Air Force, according to AFP. The unit is expected to jointly operate telescopes and radar facilities to patrol the space environment with Japan's space agency and science ministry. The new division will also provide information to the U.S. military on the state of space debris, reported AFP.

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