Japan Successfully Launches H-3 Rocket with Defense Communications Satellite
On November 4th, Japan successfully launched its fourth H-3 rocket from the Tanegashima Space Center in Kagoshima Prefecture. The mission deployed the government's X-band defense communications satellite, Kirameki-3, into orbit. This marked the first time the H-3 rocket carried a geostationary satellite.
The H-3, developed by the Japan Aerospace Exploration Agency (JAXA) and Mitsubishi Heavy Industries Ltd., is the successor to the larger H-2A rocket. This launch followed a failed first attempt, but the second, third, and now fourth launches have been successful.
The Kirameki-3 satellite, costing approximately 70 billion yen ($460 million) to develop and operate, will be maintained and operated by the Defense Ministry. It will play a crucial role in command and control of Self-Defense Forces units and other important communications.
The satellite will orbit at an altitude of approximately 36,000 kilometers above the equator, matching the Earth's rotation and appearing stationary from Earth's perspective. Reaching this geostationary orbit directly is challenging, so the satellite will first enter a long elliptical orbit, known as a geostationary transfer orbit. This connects the low Earth orbit and the targeted geostationary orbit.
Unlike the Daichi-4 satellite launched by the third H-3 rocket, which remains in a low orbit at an altitude of 628 kilometers, Kirameki-3 was launched at a higher speed. This allows it to utilize its own engines and fuel to enter the elliptical orbit and eventually reach its designated geostationary position.