Japan Successfully Launches H-3 Rocket with Defense Communications Satellite
On November 4th, 2023, Japan successfully launched its fourth H-3 rocket from the Tanegashima Space Center in Kagoshima Prefecture. The mission marked the first time the H-3 carried a "geostationary satellite," the government's X-band defense communications satellite Kirameki-3.
The launch, which took place at 3:48 p.m., followed a failed first attempt for the H-3. However, the subsequent second, third, and now fourth launches have all been successful.
Developed jointly by the Japan Aerospace Exploration Agency (JAXA) and Mitsubishi Heavy Industries Ltd., the H-3 is the successor to the larger H-2A rocket. The Kirameki-3 satellite, which will be maintained and operated by the Defense Ministry, will play a crucial role in command and control of Self-Defense Forces units and other important communications.
With a development and operation cost of approximately 70 billion yen ($460 million), the satellite will orbit the Earth at an altitude of about 36,000 kilometers above the equator, matching the Earth's rotation and appearing stationary from Earth's perspective.
Reaching geostationary orbit directly is challenging for rockets. Instead, they enter a long elliptical orbit, known as a geostationary transfer orbit, connecting an orbit near Earth with the targeted geostationary orbit.
While the Daichi-4 satellite, launched by the third H-3 rocket, flies in a low orbit at an altitude of 628 kilometers, the Kirameki-3 was flown at a higher speed to enter an elliptical orbit using its own engines and fuel. This approach allows the satellite to reach its final geostationary position.