Satellites have been playing a prominent role in Russia’s ongoing invasion of Ukraine. By monitoring the ground from outer space, these artificial bodies in orbit have proved to be very effective in battle and are having a great impact on the war situation. Both before and during the Ukraine war, satellite images revealed the scale and movements of the Russian army from moment to moment.
In addition, Ukrainians have secured access to the satellite internet service “Starlink” provided by the space company SpaceX, which is run by U.S. businessman Elon Musk. They have used Starlink not only as a means of obtaining wartime information, but also as a platform for disseminating detailed info on damage and casualties in Ukraine to the world through social media.
The Russia-Ukraine War has demonstrated why outer space is often referred to as the “fourth battlefield,” joining land, sea, and sky as warfighting domains.
However, Japan’s efforts at shoring up space security appear to be far behind those of major countries such as the U.S., China, and Russia.
The Diplomat recently sat down with General Kataoka Haruhiko, a former chief of staff of the Japan Air Self-Defense Force (JASDF) and the current vice president of the Japan Institute for Space and Security (JISS), about what Japan should do to enhance security in space.
Kataoka emphasized the need to formulate a “national space strategy” that specifies how Japan will tackle space from the perspective of security. He appealed for the early development and operation of such a space system through multilateral cooperation with the U.S. and other Western countries.
The interview was conducted in Japanese and has been translated into English.
In the Russia-Ukraine War, satellite images of private telecommunications companies are showing their power by revealing the movement of the Russian army.
The U.S. government provides Ukraine with real-time tactical information obtained through satellite and interception. Space X, led by Elon Musk, provided Starlink to Ukraine with more than 5,000 transmitters and receivers, ensuring a stable communication environment for the Ukrainian army.
Over the last five to six years, commercial activities in space have been gaining momentum. Space X is a typical example. From now on, even in the field of security, we are shifting to a situation where we must actively utilize commercial space activities. Civilian uses and military uses are becoming more well-integrated than ever before. Dual use [of space technology] is an inevitable fate. It is quite difficult to separate.
Is it fair to say that Japan’s future space security policy will proceed in unison with its only ally, the U.S.?
There is an overwhelming power gap between Japan and the U.S. As I always say, Japan cannot be like America, China, or Russia. Japan has capabilities, but considering various things such as budget and human resources, we will have to cooperate with the Western world centering on the U.S. or Five Eyes [Australia, Canada, New Zealand, the U.K., and the U.S.] to build space systems together.
Aiming for more accurate missile tracking as part of missile defense, Japan and the U.S. are already pushing ahead with plans to build a satellite constellation consisting of a large number of small satellites.
Yes. After all it is necessary to go with the U.S.
There are two types of missile defense: early warning and tracking of missiles.
Early warning of missiles is the initial detection when [a missile is] launched. Missiles can be detected without problems as we deploy large satellites in stationary orbit and polar orbit [passing over the north and south poles]. After that, the incoming missile can be tracked by ground radar.
A normal ballistic missile can be detected in the distance, but when it comes to a hypersonic missile, it crawls underneath [radar] and cannot be detected until just before it comes to us. In order to solve that, the U.S. is trying to detect and track the initial motion of the missile from space and is proceeding with the construction of the National Defense Space Architecture (NDSA) consisting of small satellites in low orbit.
So, for the early warning part, there is no problem by deploying large satellites in stationary or polar orbits. On the other hand, in the tracking part, the U.S. is currently planning to place satellites in two layers, a tracking layer for tracking and a transport layer for sending detected data in a string.
This requires a huge number of satellites that need to be placed in low orbit. This can never be built in Japan alone. Regarding missile defense, it is very important to determine how to divide the roles of early warning, detection, and tracking with the U.S.
North Korea launched eight short-range ballistic missiles toward the Sea of Japan on June 5. If a network system for small satellite constellations is created, will it be possible to detect, track, and intercept saturated missile attacks, including hypersonic missiles?
There is no situation where we cannot intercept [missiles] at all. However, if it is a saturated attack that fires dozens of shots compared to firing only one shot, the probability that we can intercept them will surely decrease. When we are talking about hypersonic missiles, the odds will fall further.
However, even if the probability [of interception] drops, it makes sense to give the public an alarm that a missile is flying toward us. It is quite meaningful to provide notices with an alarm that the missile will fall here instead of acting as if it had fallen without [authorities] knowing something.
The U.S. is working on the capability to hit a ballistic missile that has risen into space with a small bullet fired from an artificial satellite.
Yes, there are plans to intercept a ballistic missile using satellites when it goes up to space. However, this is the case when the missile comes up in space. Low-altitude orbital missiles such as hypersonic missiles cannot be intercepted. Those missiles can avoid any interception while descending to the ground in an irregular trajectory. So that’s a big challenge we face.
As clearly stated in the National Defense Strategy and the National Defense Space Strategy, the U.S. plans to respond by choosing the time and means when its own space assets are attacked. Being attacked in space does not mean a counterattack in space. The U.S. says it will hit back on the ground.
There are ground-launched missile attacks against satellites, and there are satellite-to-satellite attacks.
What should we do to increase deterrence in space? What should we do to jointly cope in space? What kind of response will we take in response to emergencies in space? What will the space operation look like? Japan must discuss these points from now on. This is inevitable when considering national strategies in space.
The Ministry of Defense plans to launch a Space Situational Awareness (SSA) satellite in 2026. This satellite isn’t just monitoring there; it’s moving closer, looking for suspicious satellites. By the time the operation begins, we have to boil down discussion on what our space strategy is and what the right of our self-defense in space is.
In 2019, seven countries, namely the U.S., the U.K., Australia, Canada, New Zealand, Germany, and France, started discussing the future of the Combined Space Operations (CSpO) initiative to strengthen their ability to grasp Space Domain Awareness (SDA) and promote data-sharing. But unfortunately Japan has not joined in. We must participate in it as soon as possible and need to build multilateral space cooperation centered on the U.S.
In addition, there is an “Operation Olympic Defender” framework between the U.S. and U.K. that jointly addresses threats in space, and Canada and Australia are now in this operation. In outer space no country has sovereignty. Multilateral cooperation is a prerequisite.
Will the JASDF become the Space Self-Defense Force or the Space Force in the future?
The space area is currently [conceived of as reaching] about to a stationary orbit, but eventually it will expand to Mars. The space area expands to infinity. The field the JASDF is in charge of will be extremely large. The name represents the body, so it is better to change it to “Air and Space Force.”
The U.S. created a new Space Force, but France made the Air and Space Force. Russia also made its aerospace forces. So just like them, it is necessary for Japan to put the word “space” in the name.