Raumfahrt - Startvorbereitung für JAXA´s H-IIA mit Global Changing Observation Mission - Climate SHIKISAI (GCOM-C)


Launch of Global Changing Observation Mission - Climate "SHIKISAI" (GCOM-C) 
and Super Low Altitude Test Satellite "TSUBAME" (SLATS) 
aboard H-IIA Vehicle No. 37

October 27, 2017 (JST)

Mitsubishi Heavy Industries, Ltd.
National Research and Development Agency
Japan Aerospace Exploration Agency (JAXA)

Mitsubishi Heavy Industries, Ltd. (MHI) and the Japan Aerospace Exploration Agency (JAXA) are pleased to announce the launch schedule for Global Changing Observation Mission - Climate "SHIKISAI" (GCOM-C) and Super Low Altitude Test Satellite "TSUBAME" (SLATS) by H-IIA launch vehicle No. 37.

Scheduled date of Launch:
December 23 (Sat.), 2017
Launch time:
10:26:22 a.m. through 10:48:22 a.m. (JST)
Reserved Launch period:
December 24 (Sun.), 2017 through January 31 (Wed.), 2018
Launch site:
Yoshinobu Launch Complex at the tanegashima Space Center

H-IIA F37 with SHIKISAI/TSUBAME onboard to be launched on December 23


The launch schedule of the H-IIA Launch Vehicle No. 37 (H-IIA F37) has been decided to be between 10:26:22 thru 10:48:22 a.m. on December 23 (Sat), 2017 (Japan Standard time). The launch will be performed by Mitsubishi Heavy Industries and JAXA. H-IIA Launch vehicle No. 37 incorporates JAXA's newly developed outcome to insert SHIKISAI and TSUBAME into different orbit altitude respectively. It will expand opportunities of multiple satellite launch and take full advantage of the capability of H-...

About Global Change Observation Mission - Climate "SHIKISAI" (GCOM-C)


Forecasting future global climate

The purpose of the GCOM (Global Change Observation Mission) project is the global, long-term observation of Earth's environment. GCOM is expected to play an important role in monitoring both global water circulation and climate change, and examining the health of Earth from space. Global and long-term observations (10-15 years) by GCOM will contribute to an understanding of water circulation mechanisms and climate change.

GCOM consists of two satellite series, the GCOM-W and GCOM-C. The GCOM-C, carrying a SGLI (Second generation GLobal Imager), conducts surface and atmospheric measurements related to the carbon cycle and radiation budget, such as clouds, aerosols, ocean color, vegetation, and snow and ice.

Characteristics of Global Change Observation Mission - Climate "SHIKISAI" (GCOM-C)

SGLI is an optical sensor for monitoring the long-term trends of aerosol-cloud interactions and for understanding the carbon cycle

The Second generation GLobal Imager (SGLI) on GCOM-C1 is an optical sensor capable of multi-channel observation at wavelengths from near-UV to thermal infrared wavelengths (380nm to 12µm.) SGLI also has polarimetry and forward / backward observation functions at red and near infrared wavelengths. SGLI obtains global observation data once every 2 or 3 days, with resolutions of 250m to 1km.

The SGLI observations will improve our understanding of climate change mechanisms through long-term monitoring of aerosols and clouds, as well as vegetation and temperatures, in the land and ocean regions. These observations will also contribute to enhancing the prediction accuracy of future environmental changes by improving sub-processes in numerical climate models. SGLI-derived phytoplankton and aerosol distributions are also used for mapping fisheries and for monitoring the transport of yellow dust and/or wildfire smoke.


Major Characteristics

Launch Vehicle H-IIA Launch Vehicle
Location Tanegashima Space Center
Weight 2000kg
Power 4kw
Design Life 5 years
Orbiter Sun-Synchronous Subrecurrent/ Recurrent
Altitude 798km
Inclination 98.6 degrees
Period 10:30±15min
Launch Date JFY 2017 (Scheduled)


H-IIA Launch vehicle No. 37 incorporates JAXA's newly developed outcome to insert SHIKISAI and TSUBAME into different orbit altitude respectively. It will expand opportunities of multiple satellite launch and take full advantage of the capability of H-IIA.


About Super Low Altitude Test Satellite "TSUBAME" (SLATS)

Creating new possibilities in satellite usage by developing new orbits

The Super Low Altitude Test Satellite "TSUBAME" (SLATS) is the first Earth observation satellite to use a super low orbit. A "super low orbit" refers to an orbit with an altitude lower than 300 km. This orbit is an undeveloped region and it has yet to be fully utilized by satellites. Satellites in a super low orbit will bring benefits such as high resolution observations for optical imagers, low power transmissions for active sensors, and cost reductions for satellite manufacturing and launches. This is due to the closer range to the Earth. 
A satellite in a super low orbit like SLATS will be exposed to air resistance, which is approximately 1,000 times greater than that of most Earth observation satellites at an altitude of 600 to 800 km. Consequently, this type of satellite will require a greater amount of fuel than conventional satellites. In order to solve the atmospheric drag issue, JAXA has adopted an ion engine. The ion engine uses fuel 10 times more efficiently than gas jets. Furthermore, we are developing a compact satellite to minimize air resistance, and will verify that our technology can support orbiting at super low altitudes over an extended period of time.
Then JAXA will take the first step toward practical application of a super low altitude satellite.

Characteristics of Super Low Altitude Test Satellite "TSUBAME" (SLATS)

SLATS will use the ion engine technology developed by JAXA in order to verify its technology for orbit control at super low altitudes.
The test satellite will also collect technical data related to the atmosphere, which will be used in the design of future satellites.
Furthermore, SLATS will photograph the Earth, and its technology will be evaluated for future Earth observation satellites.

Ion engine
For a super low altitude satellite, strong thrusters are not required, although atmospheric resistance increases. A thrust equivalent to the weight of one small coin such as a dime is sufficient. A long-life and high-fuel efficiency thruster is required. An ion engine is the most appropriate type of space engine, when considering these conditions.
From the perspective of exerting the greatest possible thrust, the propellant used in the SLATS ion engine is xenon gas, which is the same propellant that was used in Hayabusa. Furthermore, SLATS uses technology developed for KIKU No. 8, which realizes greater thrust than Hayabusa.

Atomic oxygen monitoring system
The atmosphere becomes denser as we come closer to the surface of the Earth, and a substance called "atomic oxygen" increases at super low altitudes. Atomic oxygen is known to damage 1tte golden thermal control films (Multi-Layer Insulation) that are used for satellites.
Normally, oxygen gas consists of two atoms which enter a covalent bond and form a molecule. Atomic oxygen refers to a state in which oxygen gas separates due to space radiation and ultraviolet rays, existing as a single atom. This makes atomic oxygen highly reactive and causes it to damage material used on the surface of satellites.
For SLATS, countermeasures have been taken such as applying a coating which is highly resistant to atomic oxygen to the outer surface of the multi-layer insulation. SLATS is also equipped with an atomic oxygen monitoring system which measures the concentration of atomic oxygen and the deterioration of materials when reacting with atomic oxygen. The acquired data will be used in the design of future super low altitude satellites.

Major Characteristics

Major onboard instruments 1. Atomic Oxygen Monitoring System
a) AOFS (Atomic Oxygen Fluence Sensor)
b) MDM (Material Degradation Monitor)
2. OPS (Optical Sensor) for Earth observation
Size 2.5 (X) x 5.2 (Y) x 0.9 m (Z)
(when expanded in orbit)
Weight 400 kg or less
Generated power 1,140 W or more
Design life 2 years or longer
Altitude Altitude of 268 km to 180 km
Launch Date JFY 2016 (Scheduled)

Quelle: JAXA


Update: 2.11.2017