TOKYO (AP) — The head of NASA says space security is necessary so that the United States, Japan and others can safely explore the moon and Mars.

NASA Administrator Jim Bridenstine said Wednesday that gadgets using space technology have become indispensable parts of people's lives and their safety must be preserved.

Japan and the U.S. have long cooperated in space science, including the ongoing International Space Station program.

On Tuesday, NASA and the Japan Aerospace Exploration Agency, or JAXA, confirmed Japan's participation in America's lunar and Mars exploration projects, including an Artemis lunar mission.

Bridenstine is in Japan to gain Japanese support, including funding, for the manned moon mission planned for 2024.

Tokyo and Washington are expanding their security alliance into space amid China's growing activity.