ADEOS II (Advanced Earth Observing Satellite 2) was an
Earth observation satellite
An Earth observation satellite or Earth remote sensing satellite is a satellite used or designed for Earth observation (EO) from orbit, including spy satellites and similar ones intended for non-military uses such as environmental monitoring, me ...
(EOS) launched by
NASDA
The , or NASDA, was a Japanese national space agency established on October 1, 1969 under the National Space Development Agency Law only for peaceful purposes. Based on the Space Development Program enacted by the Minister of Education, Culture, ...
,
with contributions from
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
and
CNES
The (CNES; French: ''Centre national d'études spatiales'') is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is und ...
, in December 2002.
[ ] and it was the successor to the 1996 mission
ADEOS I
ADEOS I (Advanced Earth Observing Satellite 1) was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori means "green". The mission ended in July 1997 after the satellite sustained structural damage to t ...
. The mission ended in October 2003 after the satellite's
solar panels
A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a phot ...
failed.
Mission overview
The three primary objectives of the mission, as identified by NASDA, were to:
* Regularly monitor the
water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
and
energy cycle as a part of the global climate system
* Quantitatively estimate the biomass and fundamental productivity as a part of the
carbon cycle
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and Earth's atmosphere, atmosphere of the Earth. Carbon is the main component of biological compounds as well as ...
* Detect trends in long term climate change as a result of continuing the observations started by
ADEOS I
ADEOS I (Advanced Earth Observing Satellite 1) was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori means "green". The mission ended in July 1997 after the satellite sustained structural damage to t ...
The project had a proposed minimum life of three years, with a five-year goal.
Instruments
![Adeos2-annotated](https://upload.wikimedia.org/wikipedia/commons/f/f1/Adeos2-annotated.png)
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 Reflectances (POLDER), and
SeaWinds. These instruments were designed to monitor
Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
's
water cycle
The water cycle, also known as the hydrologic cycle or the hydrological cycle, is a biogeochemical cycle that describes the continuous movement of water on, above and below the surface of the Earth. The mass of water on Earth remains fairly cons ...
, study
biomass
Biomass is plant-based material used as a fuel for heat or electricity production. It can be in the form of wood, wood residues, energy crops, agricultural residues, and waste from industry, farms, and households. Some people use the terms bi ...
in the
carbon cycle
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and Earth's atmosphere, atmosphere of the Earth. Carbon is the main component of biological compounds as well as ...
, and detect trends in long-term
climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
. The mission was established to continue the work undertaken by
ADEOS I
ADEOS I (Advanced Earth Observing Satellite 1) was an Earth observation satellite launched by NASDA in 1996. The mission's Japanese name, Midori means "green". The mission ended in July 1997 after the satellite sustained structural damage to t ...
between 1996 and 1997.
[ ]
Advanced Microwave Scanning Radiometer (AMSR)
AMSR monitors water vapor, precipitation, sea surface, wind, and ice by means of microwave radiation emanating from Earth's surface and atmosphere. It is a radiometer that operates in eight frequency bands covering 6.9 GHz to 89 GHz, and monitors the horizontal and vertical polarizations separately. With a dish of aperture, the spatial resolution is in the 89 GHz band, degrading to at 6.9 GHz.
[ ]
Global Imager (GLI)
GLI (GLobal Imager) is an optical sensor to observe
solar radiation
Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument.
Solar irradiance is measured in watts per square metre (W/m ...
reflected from
Earth's surface
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
and
map vegetation,
cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may co ...
s, etc. The data is acquired in 23 visible/near-infrared, and in 13 far infrared channels. The scanning is done by a rotating mirror covering along track and cross-track, and at a resolution of .
[ ]
Improved Limb Atmospheric Spectrometer 2 (ILAS-2)
ILAS-2 maps the vertical distribution of
O3,
NO2,
HNO3,
H2O,
CFC-11
Trichlorofluoromethane, also called freon-11, CFC-11, or R-11, is a chlorofluorocarbon (CFC). It is a colorless, faintly ethereal, and sweetish-smelling liquid that boils around room temperature. CFC-11 is a Class 1 ozone-depleting substance ...
,
CFC-12
Dichlorodifluoromethane (R-12) is a colorless gas usually sold under the brand name Freon-12, and a chlorofluorocarbon halomethane (CFC) used as a refrigerant and aerosol spray#Aerosol propellants, aerosol spray propellant. Complying with the Montr ...
,
CH4,
N2O, and
ClONO2, as well as the distribution of temperature and pressure, all in the
stratosphere
The stratosphere () is the second layer of the atmosphere of the Earth, located above the troposphere and below the mesosphere. The stratosphere is an atmospheric layer composed of stratified temperature layers, with the warm layers of air ...
. It observes the absorption spectrum in Earth's atmospheric limb in the 3-13 micron wavelength band, and in the 753-784 nm band of the occulting
Sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
. The altitude resolution is .
[ ]
Polarization and Directionality of Earth's Reflectances (POLDER)
POLDER measures the polarization, and spectral characteristics of the solar light reflected by aerosols, clouds, oceans and land surfaces. Eight narrow band wavelengths (443, 490, 564, 670, 763, 765, 865, and 910 nm) are covered by the instrument which enables identification of the physical and optical properties of the aerosols and their role in radiation budget.
[ ]
SeaWinds
SeaWinds is a
scatterometer
A scatterometer or diffusionmeter is a scientific instrument to measure the return of a beam of light or radar waves scattered by diffusion in a medium such as air. Diffusionmeters using visible light are found in airports or along roads to measur ...
that provides wind speed and direction by observing the microwave reflection from ocean surfaces. With its dish, it scans the surface along conical surfaces at 18
RPM
Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or with the notation min−1) is a unit of rotational speed or rotational frequency for rotating machines.
Standards
ISO 80000-3:2019 defines a unit of rotation as the dimensionl ...
. It provides speed at an accuracy of 2
m/s, wind direction at an accuracy of 20°, both with a spatial resolution of .
[ ]
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
Data transmission and data reception or, more broadly, data communication or digital communications is the transfer and reception of data in the form of a digital bitstream or a digitized analog signal transmitted over a point-to-point or ...
'').
The MDP device formatted mission data to be sent via the IOCS, and would process it into a
data packet
In telecommunications and computer networking, a network packet is a formatted unit of data carried by a packet-switched network. A packet consists of control information and user data; the latter is also known as the ''payload''. Control informa ...
. 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 solar cells on a jointed mast.
The AOCS was used to establish the
attitude control
Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc.
Controlling vehicle ...
following the satellite's deployment from the launch vehicle. 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
Artemis
In ancient Greek mythology and religion, Artemis (; grc-gre, Ἄρτεμις) is the goddess of the hunt, the wilderness, wild animals, nature, vegetation, childbirth, care of children, and chastity. She was heavily identified wit ...
and the
Data Relay Test Satellite (DRTS). The Artemis connection transferred information over a 26
GHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
Ka-band
The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum defined as frequencies in the range 26.5–40 gigahertz (GHz), i.e. wavelengths from slightly over one centime ...
link (for payload data) and a 2 GHz
S-band
The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the conventional ...
link (for telemetry, tracking and control data).
These signals were then
downlink
In a telecommunications network, a link is a communication channel that connects two or more devices for the purpose of data transmission. The link may be a dedicated physical link or a virtual circuit that uses one or more physical links or shar ...
ed to the
Earth Observation Center (EOC) via feeder link stations and the
Redu Station
Redu Station is an ESTRACK radio Antenna (electronics), antenna station for communication with spacecraft. The station is located in Wallonia, about one kilometre away from the village of Redu, Belgium. The ground terminals provide tracking capab ...
. ADEOS II also sent mission data directly to NASA stations, which routed information to bodies such as the EOC and sensor-providing organisations.
Launch
The mission was originally scheduled to launch aboard a
H-II launch vehicle 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-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 or ...
launch vehicle.
[ ]
The satellite was successfully launched from
Tanegashima Space Center
The (TNSC) is the largest rocket-launch complex in Japan with a total area of about 9.7 square kilometers. It is located on the southeast coast of Tanegashima, an island approximately south of Kyushu. It was established in 1969 when the ...
pad YLP-1 on 14 December 2002, aboard H-IIA 202.
Other
payload
Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...
s onboard included the Japanese MicroLabsat and WEOS devices, as well as the Australian
FedSat
FedSat (Australia's 'Federation Satellite'; sometimes FedSat 1; COSPAR 2002-056B, SATCAT 27598) was an Australian scientific research satellite launched from Tanegashima Space Center, Japan by a NASDA H-IIA launch vehicle on 14 December 2002 (N ...
.
Failure
On 23 October 2003, the
solar panel
A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...
failed. At 23:49 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 23:55 UTC, communications between the satellite and the
ground station
A ground station, Earth station, or Earth terminal is a terrestrial radio station designed for extraplanetary telecommunication with spacecraft (constituting part of the ground segment of the spacecraft system), or reception of radio waves fro ...
s ended, with no further
telemetry
Telemetry is the in situ data collection, collection of measurements or other data at remote points and their automatic data transmission, transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Gr ...
received.
Further attempts to procure telemetry data on 24 October 2003 (at 00:25 and 02:05 UTC) also failed.
Investigation
After the power failure,
JAXA
The 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 orb ...
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 flare
A solar flare is an intense localized eruption of electromagnetic radiation in the Sun's atmosphere. Flares occur in active regions and are often, but not always, accompanied by coronal mass ejections, solar particle events, and other solar phe ...
.
One hypothesis was that debris had impacted the satellite's power harness between the solar array and the
satellite bus
A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held.
Bus-derived satellites are opposed to specially produced satellites. Bus-d ...
. The harness was a core of wires enclosed in
multi-layer insulation
Multi-layer insulation (MLI) is thermal insulation composed of multiple layers of thin sheets and is often used on spacecraft and cryogenics. Also referred to as superinsulation, MLI is one of the main items of the spacecraft thermal design, pri ...
. The debris impact was theorised to have caused an
electric arc
An electric arc, or arc discharge, is an electrical breakdown of a gas that produces a prolonged electrical discharge. The electric current, current through a normally Electrical conductance, nonconductive medium such as air produces a plasma (p ...
.
The mission officially ended at the end of October 2003, with JAXA conceding that the "possibility of restoring the operations of Midori II
asextremely slim". The mission, which had cost approximately 70 billion
Yen
The is the official currency of Japan. It is the third-most traded currency in the foreign exchange market, after the United States dollar (US$) and the euro. It is also widely used as a third reserve currency after the US dollar and the e ...
(US$570 million)
was only able to recoup an estimated 300 million Yen through insurance.
References
External links
*
{{Orbital launches in 2002
Earth observation satellites of Japan
Spacecraft launched in 2002
Spacecraft launched by H-II rockets
Derelict satellites orbiting Earth