Space Transportation Systems Epsilon Launch Vehicle

In Operation

About Epsilon Launch Vehicle

The Epsilon Launch Vehicle is a solid-fuel rocket designed to lower the threshold to space hitherto regarded as “special” and to usher in an age in which everyone can make active use of space. It has achieved a world-class, satellite-friendly environment by reducing vibration and noise as well as buffering shocks during satellite separation. Epsilon-4 established the technology for the simultaneous launch of multiple satellites, and Epsilon-5 succeeded in inserting nine satellites, the most ever, into their scheduled orbit. Furthermore, the development of the “Epsilon S Launch Vehicle” has started to strengthen Epsilon's international competitiveness by maximizing synergistic effects with the H3 Launch Vehicle with the aim at launching the demonstration flight in FY2023. Through these efforts, we intend to make a full-scale enter into the launch market for small satellites including nanosatellites, the demand for which is expected to grow in the future.

Compact Launch System

Epsilon's automated inspection and its small, simple launch pad are key elements for our compact launch system.

From experimental models to enhanced launch vehicles

Technologies from the H-IIA and M-V rockets were carried over to save time and cut development costs. M-V launch control operations were revamped and mobile control introduced to renovate the operational and equipment dimensions of rocket launch procedures. Following the successful launch of an experimental model, further improvements were undertaken to optimize rocket airframe performance. These enhancements were completed with Epsilon-2 and Epsilon-3.

Epsilon-4 featured a simultaneous launch of multiple satellites, establishing the technology for accurately inserting individual satellites into their respective orbits. This technology was developed to make the Epsilon Launch Vehicle internationally competitive in the launch market for mini-/micro-satellites and CubeSats, where demand is expected to expand globally.

From enhanced launch vehicles to Epsilon S

Technological advances in miniaturization and integration have spurred launch demand for mini-/micro-satellites and CubeSats in satellite launch markets inside and outside Japan. Created to meet this demand, the new “Epsilon S Launch Vehicle Project” aims to expand the scale of Japan’s space transport industry by transferring the Epsilon Launch Vehicle program to the private sector and developing it into an autonomous and sustainable transport system. An Epsilon S demonstration launch is tentatively scheduled for FY2023.

Project Topics

Jun. 12, 2020 Updated

Signing of the “Basic Agreement on the Development of the Epsilon S Launch Vehicle and the Implementation of the Launch Service Business”

Signing of the “Basic Agreement on the Development of the Epsilon S Launch Vehicle and the Implementation of the Launch Service Business”

The Japan Aerospace Exploration Agency (JAXA) is pleased to announce that it has entered into the Basic Agreement with IHI AEROSPACE CO., LTD. (IA) on the development of the Epsilon S Launch Vehicle and its launch service business.  The Epsilon S Launch Vehicle, which will be developed based on the current Enhanced Epsilon, is aimed at strengthening Epsilon’s international competitiveness in the satellite launch market by achieving synergist...

Characteristics of Epsilon Launch Vehicle

Major Characteristics

Epsilon Major Characteristics

Test Flight Model Enhanced Model
Length (m) 24 26
Mass (t) 91 95.4
Diameter (m) 2.6

Epsilon Launch Vehicle Launch Capacity

Specifications Standard Configuration
Three-staged Solid Propellant Launch Vehicle
Optional Configuration
Three-staged Solid Propellant Launch Vehicle
+ Compact Liquid Propulsion System
Low Earth Orbit (LEO) 1200kg
(Perigee 250km x
Apogee 500km)
(500km circle)
Sun-Synchronous Orbit (SSO) - 450kg
(500km circle)

Launch Records

Mission talk by team leaders

Project Manager Yasuhiro Morita

Here are messages from Project Managers.