ADEOS II
Encyclopedia
ADEOS II was an Earth observation satellite
launched by NASDA, NASA
and CNES
in December 2002. Its Japanese
name was Midori 2, and it was the successor to the 1996 mission ADEOS I
. The mission ended in October 2003 after the satellite's solar panels failed.
The project had a proposed minimum life of three years, with a five-year goal.
rocket in February 2002. This was postponed as the Japanese Space Activities Commission would not launch without having three successful missions aboard the new H-IIA
rocket.
The satellite was successfully launched from Tanegashima Space Center
pad YLP-1 on 14 December 2002, aboard H-2A-202. Other payloads onboard included the Japanese
MicroLabsat and WEOS
devices, as well as the Australian
FedSat
.
received. Further attempts to procure telemetry data on 24 October (at 0025 and 0205 UTC) also failed.
.
One hypothesis was that debris had impacted the satellite's power harness between the solar array and the satellite bus
. The harness was a core of wires enclosed in multi-layer insulation
. The debris impact was theorised to have caused an electric arc
.
The mission officially ended at the end of October 2003, with JAXA conceding that the "possibility of restoring the operations of Midori II [was] extremely slim." The mission, which had cost approximately 70 billion Yen (US$570 million) was only able to recoup an estimated 300 million Yen through insurance.
(POLDER), and SeaWinds. These instruments were designed to monitor Earth
's water cycle
, study biomass
in the carbon cycle
, and detect trends in long-term climate change
. The mission was established to continue the work undertaken by ADEOS I
between 1996 and 1997.
The C&DH subsystem received and decoded the satellite's tracking control command signals and acted as a processing interface between the instruments. It was capable of adjusting settings on the instruments – such as temperature and voltage. The IOCS was used to communicate with data relay satellites (see Data transfer).
The MDP device formatted mission data to be sent via the IOCS, and would process it into a data packet. The ODR was a large-volume storage device that used an optical magnetic disk system
. The EPS provided power to the satellite's subsystems. The PDL managed the satellite's solar panel, and transferred electrical energy to the EPS. The solar panel was capable of generating 5 kW using 55,680 cells on a jointed mast.
The AOCS was used to establish the attitude control following the satellite's deployment from the rocket. It was subsequently used to adjust the satellite's attitude, orbit, and solar paddle. The AOCS was equipped with a number of attitude sensors, including a control-standard unit (IRC), an Earth sensor (ESA), and a fine sun sensor assembly (FSSA).
The RCS was used to generate propulsion power for attitude adjustments after deployment and control orbit using data from the AOCS.
and the Data Relay Test Satellite (DRTS). The Artemis connection transferred information over a 26 GHz Ka band
link (for payload data) and a 2 GHz S band
link (for telemetry, tracking and control data).
These signals were then downlinked to the Earth Observation Center (EOS) via feeder link stations and the Redu Station
. ADEOS II also sent mission data directly to NASA stations, which routed information to bodies such as the EOC and sensor-providing organisations.
Earth observation satellite
Earth observation satellites are satellites specifically designed to observe Earth from orbit, similar to reconnaissance satellites but intended for non-military uses such as environmental monitoring, meteorology, map making etc....
launched by NASDA, NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
and CNES
CNES
The is the French government space agency . Established under President Charles de Gaulle in 1961, its headquarters are located in central Paris and it is under the supervision of the French Ministries of Defence and Research...
in December 2002. Its Japanese
Japanese language
is a language spoken by over 130 million people in Japan and in Japanese emigrant communities. It is a member of the Japonic language family, which has a number of proposed relationships with other languages, none of which has gained wide acceptance among historical linguists .Japanese is an...
name was Midori 2, and it was the successor to the 1996 mission ADEOS I
ADEOS I
ADEOS I was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori, means "green"....
. The mission ended in October 2003 after the satellite's solar panels failed.
Mission overview
The three primary objectives of the mission, as identified by NASDA, were to:- Regularly monitor the water and energy cycle as a part of the global climate system
- Quantitatively estimate the biomass and fundamental productivity as a part of the carbon cycleCarbon cycleThe carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth...
- Detect trends in long term climate change as a result of continuing the observations started by ADEOSADEOS IADEOS I was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori, means "green"....
The project had a proposed minimum life of three years, with a five-year goal.
Launch
The mission was originally scheduled to launch aboard a H-IIH-II
The H-II rocket was a Japanese satellite launch system, which flew seven times between 1994 and 1999, with five successes. It was developed by NASDA in order to give Japan a capability to launch larger satellites in the 1990s. It was the first two-stage liquid-fuelled rocket Japan made using only...
rocket in February 2002. This was postponed as the Japanese Space Activities Commission would not launch without having three successful missions aboard the new H-IIA
H-IIA
H-IIA is an active expendable launch system operated by Mitsubishi Heavy Industries for the Japan Aerospace Exploration Agency . The liquid-fueled H-IIA rockets have been used to launch satellites into geostationary orbit, to launch a lunar orbiting spacecraft, and to launch an interplanetary...
rocket.
The satellite was successfully launched from Tanegashima Space Center
Tanegashima Space Center
The is one of Japan's space development facilities. It is located on Tanegashima, an island located 115 km south of Kyūshū. It was established in 1969 when the National Space Development Agency of Japan was formed...
pad YLP-1 on 14 December 2002, aboard H-2A-202. Other payloads onboard included the Japanese
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
MicroLabsat and WEOS
WEOS
WEOS is a college radio station licensed to Geneva, New York, broadcasting primarily on 89.7 FM across the Finger Lakes region of New York. It also broadcasts on a smaller relay transmitter on 90.3FM in Geneva . The station is owned by The Colleges of the Seneca, Inc., the legal name of Hobart...
devices, as well as the Australian
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
FedSat
FedSat
FedSat is an Australian scientific research satellite launched from Tanegashima Space Center, Japan by a NASDA H-IIA launch vehicle in December 2002...
.
Failure
On 23 October 2003, the solar panel failed. At 2349 UTC, the satellite switched to "light load" operation due to an unknown error. This was intended to power down all observation equipment to conserve energy. At 2355 UTC, communications between the satellite and the ground stations ended, with no further telemetryTelemetry
Telemetry is a technology that allows measurements to be made at a distance, usually via radio wave transmission and reception of the information. The word is derived from Greek roots: tele = remote, and metron = measure...
received. Further attempts to procure telemetry data on 24 October (at 0025 and 0205 UTC) also failed.
Investigation
After the power failure, JAXA (NASDA's successor) formed the Midori II anomaly investigation team. Analysis of data received before transmissions ceased showed that the solar panel's power output had decreased from 6 kW to 1 kW. The investigation team began surveying the mission to establish whether the failure was due to a technical malfunction or a solar flareSolar flare
A solar flare is a sudden brightening observed over the Sun surface or the solar limb, which is interpreted as a large energy release of up to 6 × 1025 joules of energy . The flare ejects clouds of electrons, ions, and atoms through the corona into space. These clouds typically reach Earth a day...
.
One hypothesis was that debris had impacted the satellite's power harness between the solar array and the satellite bus
Satellite bus
A satellite bus or spacecraft bus is the general model on which multiple-production satellite spacecraft are often based. The bus is the infrastructure of a spacecraft, usually providing locations for the payload .They are most commonly used for geosynchronous satellites, particularly...
. The harness was a core of wires enclosed in multi-layer insulation
Multi-layer insulation
Multi-layer insulation, or MLI, is thermal insulation composed of multiple layers of thin sheets often used on spacecraft. It one of the main items of the spacecraft thermal design, mainly intended to reduce heat loss by thermal radiation. In its basic form, it does not appreciably insulate...
. The debris impact was theorised to have caused an electric arc
Electric arc
An electric arc is an electrical breakdown of a gas which produces an ongoing plasma discharge, resulting from a current flowing through normally nonconductive media such as air. A synonym is arc discharge. An arc discharge is characterized by a lower voltage than a glow discharge, and relies on...
.
The mission officially ended at the end of October 2003, with JAXA conceding that the "possibility of restoring the operations of Midori II [was] extremely slim." The mission, which had cost approximately 70 billion Yen (US$570 million) was only able to recoup an estimated 300 million Yen through insurance.
Instruments
The satellite was equipped with five primary instruments – Advanced Microwave Scanning Radiometer (AMSR), Global Imager (GLI), Improved Limb Atmospheric Spectrometer-II (ILAS-II), Polarization and Directionality of the Earth's ReflectancesPOLDER
POLDER is a passive optical imaging radiometer and polarimeter developed by the French space agency CNES.- Description :...
(POLDER), and SeaWinds. These instruments were designed to monitor Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
's water cycle
Water cycle
The water cycle, also known as the hydrologic cycle or H2O cycle, describes the continuous movement of water on, above and below the surface of the Earth. Water can change states among liquid, vapor, and solid at various places in the water cycle...
, study biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
in the carbon cycle
Carbon cycle
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth...
, and detect trends in long-term climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
. The mission was established to continue the work undertaken by ADEOS I
ADEOS I
ADEOS I was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori, means "green"....
between 1996 and 1997.
Subsystems
In addition to the five main instruments, nine avionic subsystems were allocated to the bus module. These were the Communication and Data-Handling Subsystem (C&DH), Inter-Orbit Communication Subsystem (IOCS), Mission Data Processing Subsystem (MDPS), Optical Data Recorder (ODR), Electrical Power Subsystem (EPS), Paddle Subsystem (PDL), Attitude and Orbit Control Subsystem (AOCS), Reaction Control Subsystem (RCS), and the Direct Transmission Subsystem (DTL).The C&DH subsystem received and decoded the satellite's tracking control command signals and acted as a processing interface between the instruments. It was capable of adjusting settings on the instruments – such as temperature and voltage. The IOCS was used to communicate with data relay satellites (see Data transfer).
The MDP device formatted mission data to be sent via the IOCS, and would process it into a data packet. The ODR was a large-volume storage device that used an optical magnetic disk system
Magnetic storage
Magnetic storage and magnetic recording are terms from engineering referring to the storage of data on a magnetized medium. Magnetic storage uses different patterns of magnetization in a magnetizable material to store data and is a form of non-volatile memory. The information is accessed using...
. The EPS provided power to the satellite's subsystems. The PDL managed the satellite's solar panel, and transferred electrical energy to the EPS. The solar panel was capable of generating 5 kW using 55,680 cells on a jointed mast.
The AOCS was used to establish the attitude control following the satellite's deployment from the rocket. It was subsequently used to adjust the satellite's attitude, orbit, and solar paddle. The AOCS was equipped with a number of attitude sensors, including a control-standard unit (IRC), an Earth sensor (ESA), and a fine sun sensor assembly (FSSA).
The RCS was used to generate propulsion power for attitude adjustments after deployment and control orbit using data from the AOCS.
Data transfer
ADEOS II transferred data to and from ArtemisArtemis (satellite)
Artemis is a geostationary earth orbit satellite for telecommunications, built for and owned by ESA. The Artemis satellite operates at the 21.5E orbital position....
and the Data Relay Test Satellite (DRTS). The Artemis connection transferred information over a 26 GHz Ka band
Ka band
The Ka band covers the frequencies of 26.5–40 GHz. The Ka band is part of the K band of the microwave band of the electromagnetic spectrum. This symbol refers to "K-above" — in other words, the band directly above the K-band...
link (for payload data) and a 2 GHz S band
S band
The S band is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. It is part of the microwave band of the electromagnetic spectrum...
link (for telemetry, tracking and control data).
These signals were then downlinked to the Earth Observation Center (EOS) via feeder link stations and the Redu Station
Redu Station
Redu Station is an ESTRACK radio antenna station for communication with spacecraft. The station is located about one kilometre away from the village of Redu, Belgium. The ground terminals provide tracking capabilities in C-band, L-band, S-band, Ku band, and Ka band as well as provide in-orbit tests...
. ADEOS II also sent mission data directly to NASA stations, which routed information to bodies such as the EOC and sensor-providing organisations.