An expendable launch system is a launch vehicle that can be launched only once, after which its components are either destroyed during reentry or discarded in space. ELVs typically consist of several rocket stages that are discarded sequentially as their fuel is exhausted and the vehicle gains altitude and speed. As of 2024, less and less satellites and human spacecraft are launched on ELVs in favor of reusable launch vehicles. However, there are many instances where a ELV may still have a compelling use case over a reusable vehicle. ELVs are simpler in design than reusable launch systems and therefore may have a lower production cost. Furthermore, an ELV can use its entire fuel supply to accelerate its payload, offering greater payloads. ELVs are proven technology in widespread use for many decades.
The Japan Aerospace Exploration Agency (JAXA) is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into orbit, and is involved in many more advanced missions such as asteroid exploration and possible human exploration of the Moon. Its motto is One JAXA and its corporate slogan is Explore to Realize.
The H-II Transfer Vehicle (HTV), also called Kounotori, is an expendable, automated cargo spacecraft used to resupply the Kibō Japanese Experiment Module (JEM) and the International Space Station (ISS). The Japan Aerospace Exploration Agency (JAXA) has been working on the design since the early 1990s. The first mission, HTV-1, was originally intended to be launched in 2001. It launched at 17:01 UTC on 10 September 2009 on an H-IIB launch vehicle. The name Kounotori was chosen for the HTV by JAXA because "a white stork carries an image of conveying an important thing, therefore, it precisely expresses the HTV's mission to transport essential materials to the ISS". The HTV is very important for resupplying the ISS because after the retirement of the Space Shuttle it is the only vehicle that can transfer new 41.3 in (105 cm) wide International Standard Payload Racks (ISPRs) and dispose old ISPRs that can fit the 51 in (130 cm) wide tunnels between modules in the US Orbital Segment.
H-IIA (H-2A) is an active expendable launch system operated by Mitsubishi Heavy Industries (MHI) for the Japan Aerospace Exploration Agency. These liquid fuel rockets have been used to launch satellites into geostationary orbit; lunar orbiting spacecraft; Akatsuki, which studied the planet Venus; and the Emirates Mars Mission, which was launched to Mars in July 2020. Launches occur at the Tanegashima Space Center. The H-IIA first flew in 2001. As of February 2024, H-IIA rockets were launched 48 times, including 42 consecutive missions without a failure, dating back to 29 November 2003.
S-Series is a fleet of sounding rockets funded by the Japan Aerospace Exploration Agency (JAXA) that have been in service since the late 1960s. Manufactured by IHI Aerospace and operated by the Institute of Space and Astronautical Science (ISAS). The nomenclature of the S-Series rockets is the number of "S"s indicates the number of stages, and the following number details the diameter of the craft in millimeters. For example, the S-310 is a single stage rocket with a diameter of 310 mm.
H-IIB (H2B) was an expendable space launch system jointly developed by the Japanese government's space agency JAXA and Mitsubishi Heavy Industries. It was used to launch the H-II Transfer Vehicle cargo spacecraft for the International Space Station. The H-IIB was a liquid-fueled rocket, with solid-fuel strap-on boosters and was launched from the Tanegashima Space Center in southern Japan. H-IIB made its first flight in 2009, and had made a total of nine flights through 2020 with no failures.
The LE-5 liquid rocket engine and its derivative models were developed in Japan to meet the need for an upper stage propulsion system for the H-I and H-II series of launch vehicles. It is a bipropellant design, using LH2 and LOX. Primary design and production work was carried out by Mitsubishi Heavy Industries. In terms of liquid rockets, it is a fairly small engine, both in size and thrust output, being in the 89 kN (20,000 lbf) and the more recent models the 130 kN (30,000 lbf) thrust class. The motor is capable of multiple restarts, due to a spark ignition system as opposed to the single use pyrotechnic or hypergolic igniters commonly used on some contemporary engines. Though rated for up to 16 starts and 40+ minutes of firing time, on the H-II the engine is considered expendable, being used for one flight and jettisoned. It is sometimes started only once for a nine-minute burn, but in missions to GTO the engine is often fired a second time to inject the payload into the higher orbit after a temporary low Earth orbit has been established.
The N-I or N-1 was a derivative of the American Thor-Delta rocket, produced under license in Japan. The N stood for "Nippon" (Japan). It used a Long Tank Thor first stage, a Mitsubishi Heavy Industries-designed LE-3 engine on the second stage, and three Castor SRMs. Seven were launched between 1975 and 1982, before it was replaced by the N-II. Six of the seven launches were successful, however on the fifth flight, there was recontact between the satellite and the third stage, which caused the satellite to fail.
The Japanese space program originated in the mid-1950s as a research group led by Hideo Itokawa at the University of Tokyo. The size of the rockets produced gradually increased from under 30 cm (12 in) at the start of the project, to over 15 m (49 ft) by the mid-1960s. The aim of the original research project was to launch a man-made satellite.
The Epsilon Launch Vehicle, or Epsilon rocket, is a Japanese solid-fuel rocket designed to launch scientific satellites. It is a follow-on project to the larger and more expensive M-V rocket which was retired in 2006. The Japan Aerospace Exploration Agency (JAXA) began developing the Epsilon in 2007. It is capable of placing a 590 kg payload into Sun-synchronous orbit.
Kounotori 6 (こうのとり6号機), also known as HTV-6, was the sixth flight of the H-II Transfer Vehicle, an uncrewed cargo spacecraft launched to resupply the International Space Station. It was launched at 13:26:47 UTC on 9 December 2016 aboard H-IIB launch vehicle from Tanegashima Space Center.
The LE-9 is a liquid cryogenic rocket engine burning liquid hydrogen and liquid oxygen in an expander bleed cycle. Two or three will be used to power the core stage of the H3 launch vehicle.
SRB-A is a series of Japanese solid-fueled rocket booster manufactured by IHI Corporation for use on the H-IIA, H-IIB, and Epsilon rockets.
Kounotori 7 (こうのとり7号機), also known as HTV-7, was the seventh flight of the H-II Transfer Vehicle (HTV), an uncrewed cargo spacecraft launched on 22 September 2018 to resupply the International Space Station.
TRICOM-1R, also known as Tasuki, was a Japanese nanosatellite that was launched during the SS-520-5 sounding rocket test launch on 3 February 2018, with a mission to conduct store and forward data relay and Earth observation using a set of cameras.
Interstellar Technologies, Inc., or IST, is a Japanese private spaceflight company aiming to eventually build a launch vehicle for smallsats under 100 kg. It is a rocket spacelaunch company developing the MOMO suborbital rocket and the ZERO orbital launch vehicle. Interstellar's stated goal is to reduce the cost of access to space.
The Innovative Satellite Technology Demonstration Program is a series of spacecraft missions for testing technology and ideas put forward by universities and private companies. The program demonstrates various experimental devices and technology in space by providing flight opportunities. It is managed by the JAXA Research and Development Directorate. According to JAXA, the goal of this program is to test high risk, innovative technology that will lead to the space industry gaining competitiveness in the international field.
DRUMS is an experimental spacecraft that will test proximity operation near space debris. The microsatellite carries two 'mock space debris' which once deployed will be used as a target for demonstrating approach and contact.
RAISE-2 was a smallsat for technology demonstration, part of the Japanese space agency JAXA's Innovative Satellite Technology Demonstration Program. RAISE-2 was launched on 9 November 2021 as the main satellite of Innovative Satellite Technology Demonstration-2. RAISE-2 was developed by Mitsubishi Electric.
