Priroda

Quick facts

Overview

Priroda

Priroda (“nature”) is a multisensor research module (orbital complex) for Russia's orbital Mir station (“peace”) dedicated to the observation of the environment. Major partners/organizations involved: Roskosmos (Russian Space Agency), RAS (Russian Academy of Sciences), RSC (Rocket Space Corporation) Energia, S.. P. Korolev, Moscow region - the prime contractor and developer of the Mir Station and its modules; RNII KP (Russian Institute of Space Device Engineering), IRE-RAS (Institute of Radioengineering and Electronics), NPO Planeta, etc. ^{1) 2) 3)}

For reasons of context, a few items on the Mir station and its components are given as well as some background information to put the Priroda module into proper perspective. The assembly phase of Mir lasted for a period of 10 years. The Mir station had a design life of 3.5 years; it remained in orbit for 15 years.

With the arrival of the Priroda module, the Mir station assumed a total mass of ~ 120 tons and a total pressurized volume of ~ 350 m³.

Orbit: The Mir station had a near-circular orbit with an altitude between 350 - 410 km (depending on reboosts) with an inclination of 51.6º.

The Mir station was deorbited on March 21, 2001 with a final reentry into the Pacific Ocean on March 23, 2001.
The decision to end Mir's operation was the result of two factors: age and operational expense.

Background:

In the 1980s, an awareness of environmental protection was gaining some recognition in the USSR (Union of Soviet Socialist Republics). Soviet citizens know the environment as priroda, a word which is literally translated as ”nature,” but whose meaning encompasses all aspects of life within the biosphere. Priroda connotes ”mother nature,” a nurturing and even moral realm, while also suggesting, the ambient environment and all ecological systems. Protection of the environment has been elevated to a top priority in the Soviet Union because the Soviet's harm to priroda throughout that nation has become acute. ⁶⁾

In order to reverse pollution's environmentally damaging trends, to stop the depletion of natural resources and to restore degraded conditions resulting from years of neglect during the heavy and rapid industrialization period in the USSR, the Communist Party has decided to radically restructure its environmental protection programs as part of an extraordinary redesign of its economy and society generally. Known as perestroika, this radical restructuring is characterized by Soviet President Mikhail S. Gorbachev as ”a revolution from above” (Ref. 6).

In 1985, General Secretary Mikhail S. Gorbachev and President Ronald W. Reagan met in Geneva, Switzerland. They had just received the report of the tenth meeting of USA-USSR Joint Committee on Cooperation in the Field of Environmental Protection, held the prior week in Moscow. Acknowledging the usefulness of those meetings, their joint statement concluding the summit meeting observed that ”both sides agreed to contribute to the preservation of the environment - a global task through joint research and practical measure” (Ref. 6).

The Priroda module was originally an all-Soviet remote sensing project for combined civilian and military surveillance of the Earth. Then in 1985, the Priroda project took on an international aspect when experiments scheduled for launch aboard smaller satellites within the Interkosmos program were moved to Priroda. However, throughout the planning and development phases, the Priroda project was plagued by many reconfigurations, setbacks and delays. The Priroda module was originally scheduled for delivery in the late 1980s, then the launch was scheduled for 1990; but by 1990 this had been pushed back to 1992. ^{7) 8)}

With the end of the Cold War in early 1990s and the collapse of the former USSR, construction work stopped and the Priroda module was put into storage since the Russian space program was in deep financial trouble. - Already in 1990, the US and the USSR began a joint program of scientific and manned space flight studies in response to agreements reached by the Bush Administration. Initial activities included the conduct of medical experiments studying the effects of long-duration space flight on board Mir. Provisions were made for the flight of a Russian cosmonaut on Space Shuttle, and of an American astronaut on board Mir (Ref. 13).

In April 1993, General Secretary Boris Yeltsin met President Bill Clinton in Vancouver, Canada. The summit resulted in an agreement to establish a US-Russian commission on technological cooperation in the fields of energy and space, chaired by Russian Prime Minister Viktor Chernomyrdin and Vice President Al Gore.

On Dec. 16, 1993, a cooperative Shuttle/Mir agreement was signed between officials of the newly established Russian Space Agency (Yuri N. Koptev) and NASA (Daniel S. Goldin) involving a series of 10 Shuttle flights to the Mir station in the timeframe 1995-1998. ⁹⁾

NASA agreed also to provide funding to complete the Spektr and Priroda modules for Mir using US funds, providing 600 to 700 kg of US experiments to be installed. The joint cooperative space program of the United States and the Russian Federation, involving the Mir station and its modules, spelled out the following goals: ¹⁰⁾

• First, the program permits NASA to develop, maintain, and enhance capabilities and operations to allow humans to live and work continuously in space.

• Second, by establishing a relationship with Russia as an international partner for the human exploration and exploitation of space, the United States can reduce the cost of future US space initiatives by applying Russian-developed technology.

• Third, by flying Space Shuttle missions to the Russian Mir, the United States can enhance its understanding of long-duration operations, and gain life sciences and microgravity research benefits from long-duration experimentation.

• Fourth, early cooperation with the Russian partners permits NASA to develop common systems and operating procedures which will increase the probability of success and mitigate risks in the design, assembly, and operation of the International Space Station (ISS) in which Russia is a full partner.

• Fifth, by engaging Russia in constructive space work, the United States can advance its foreign policy initiatives.

• Finally, this relationship between the US and Russian space agencies advances US national space programs as well as US aerospace industry.

As it turned out, the greatest benefits of the NASA/Mir program was the ability and necessity of the Russian and American program's engineering and management staffs to work together, gaining mutual experience, trust and respect.

In 1995, the Priroda mission was accompanied by an extensive international scientific program with contributions from 12 nations. The international partners of the Priroda program were: Bulgaria, Czech Republic and Slovakia, France, Germany, Independent States Community, Italy, Poland, Switzerland, and USA. The scientific program was focussed on 4 major tasks:

1) Development of optimal multisensoral remote sensing methodology

2) Investigation of the remote sensing instrumentation as being the optimal composition

3) Improvement of radiative transfer models

4) Methodical questions on evaluation, interpretation and collection of data.

The science objectives of the internationally provided experiments on Priroda were to support the research program: ¹¹⁾

• Determination of the atmosphere-ocean system characteristics

- Global survey by using passive sensing techniques

- Sea surface temperature determination

- Wind speeds and direction

- Surface roughness due to wind

- Ocean color characteristics

- Ocean bioproductivity investigations

- Ice cover determination

- Comparison of radiation and reflection characteristics of the sea surface in the microwave range

• Measurements of the land local characteristics

- Snow cover

- Soil investigations

- Vegetation

- Earth surface mapping at different wavelength ranges for solid Earth research

• Measurements of optical characteristics of the atmosphere

- Large-scale atmospheric processes

- Atmosphere-ocean interactions

- Lower stratosphere and troposphere physical parameters

- Ozone experiment

- Measurements of the concentrations of trace gases in the atmosphere.

• Ecological investigations

The great variety of observation techniques employed by the various instruments were expected to provide synergies on many levels in the evaluation and interpretation of the data (for instance: the combination of SAR and radar altimeter data with MW radiometer data in ocean research).

Priroda Module

Priroda was the seventh and final module of the Mir Space Station. Its primary purpose was to conduct Earth resource experiments through remote sensing and to develop and verify remote sensing methods. Originally, Priroda was designed to to carry a deployable solar array. However, due to delays, solar arrays were planned for other parts of Mir and a solar array was not included in the launch configuration. ^{12) 13)}

With a basic structure mass of 19,700 kg, a volume of more than 66 m³, a length of about 12 m, and a maximum diameter of 4.35 m, Priroda is the most sophisticated and complex Earth observation spacecraft undertaken by the Russian Federation.

Priroda was originally designed to carry a deployable solar array. However, due to delays, solar arrays were planned for other parts of Mir and a solar array was not included in the launch configuration. Instead, during free flight, Priroda was powered by two redundant sets of batteries totaling 168 cells.

The Priroda module consisted of an unpressurized instrument compartment and a habitable instrument/payload compartment. The unpressurized compartment contains propulsion system components, EVA handrails, and scientific equipment. The module had one active docking assembly located along its longitudinal axis. The nominal location of the Priroda module within the Mir Station was along the +Z axis.

Launch

The launch of the Priroda module took place on April 23, 1996 aboard a Proton-K launch vehicle from the Baikonur Cosmodrome (Mir docking on April 26, 1996). Nominal mission life = 2-3 years.

Orbit (Mir Station complex): Near circular orbit, altitude of 385 km x 393 km (typical), inclination = 51.6º, period = 89.1 minutes.

The Priroda module was capable of autonomous flight prior to its docking with Mir, and included significant new service systems that enhanced Mir's Earth observation and telemetry capabilities.

The Priroda module included a payload shroud, the instrument/payload compartment, and an instrument module. The shroud protected the module and external equipment from aerodynamic effects during the launch sequence. The instrument compartment was the main portion of the module and housed spacecraft systems, experiments, and the pressurized area for crew operations. The unpressurized section of the instrument module housed spacecraft systems.

The instrument/payload compartment was divided lengthwise into three sections. The first compartment principally housed module systems hardware while the later two housed primarily payload systems. All of the US designed hardware was installed in the instrument/payload compartment.

The instrument/payload compartment was divided into an inner habitation and work compartment and an outer instrumentation compartment. The two were divided by aluminum-magnesium coated plastic panels. The panels provide a fire break and formed a significant portion of the module’s environmental control system, allowing conditioned air to flow through the crew compartment before returning through the instrumentation compartment (Ref. 13).

Sensor Complement

Priroda Passive Microwave Instruments

The were developed and built by SRB/MPEI (Special Research Bureau/Moscow Power Engineering Institute), consisting of the following instrument blocks: IKAR-N, IKAR-D, IKAR-P, and a scanning radiometer.^{14) 15)}

IKAR-D (Delta)

IKAR-D is a three-channel scanning microwave radiometer at wavelengths of 0.3, 0.8, and 1.35 cm and a look angle of 40º from nadir.

IKAR-P (Panorama)

IKAR-P is a three-channel scanning microwave radiometer (RP-225) at a wavelength of 2.25 cm, and a five-channel panorama radiometer RP-600 at 6.0 cm. Both with a look angle of 40º against nadir. Objective: Measurement of sea surface temperatures (SST). Scanning is performed by a rotating reflector, a non-symmetric truncated paraboloid with a diameter of 700 mm. Conical horns serve as exciters, they separate each waveband. The reflector (mass <0.3 kg) consists of two layers of glass fiber and a radio-reflecting layer in the form of nickel coating. The look angle is 40º against nadir. The swath width is about 680 km. A full scan cycle is 2.56 s. Calibrations are performed during each scan cycle by internal noise generators and antenna views to cold space. A flat mirror, not interfering with the measurement process, is used for cold space calibrations. ¹⁶⁾

The receivers are Dicke-type radiometers. The control of modulators, the synchronization of drive engine operations and the control of standard noise generators is supervised by a digital data processing unit.

IKAR-N (Nadir)

This assembly consisted of five microwave radiometers (R-30, R-80, P-135, R-225P, and RP-600) at wavelengths of 0.3 cm, 0.8 cm, 1.35 cm, 2.25 cm, and 6.0 cm in nadir direction. R-225P can also measure different polarizations. The swath width is 60 km, pixel size = 60 km. Objective: Measurement of microwave radiation (emission) at the atmosphere/sea surface interface. The IKAR-N instrument is similar to the radiometers of the IKAR-P complex. Some differences are in the construction of the receiving equipment (rectangular horns, are used for each frequency).

R-400

The instrument is a one-channel polarization scanner microwave radiometer. Wavelength of 4.0 cm (7.5 GHz). Look angle also 40º against nadir. Objective: Measurement of the thermal radiation of the Earth surface (radio wave range).

Priroda active microwave equipment: (SAR Travers, Greben)

Travers is a side-viewing radar system with synthetic aperture (SAR, measurement in two frequencies). Russian sensor, built by MEI (Moscow Power Engineering Institute). Objective: generation of radar images of the Earth's surface (land and ocean). Wavelengths of scanning beam: 9.2 cm (3.28 GHz, S-band), and 23 cm (1.28 GHz, L-band).

Greben Altimeter

A Ku-band (13.76 GHz) nadir-viewing radar altimeter of Russia providing a pulse-limited footprint of 2.3 km from an orbital altitude of 400 km. Pulse length = 1.7 µs (uncompressed) and 12.5 ns (compressed). The measurement accuracy in range of the instrument is ~ 10 cm. The beam-limited footprint is 13 km.

Priroda optical equipment (ISTOK-1, MOS-A, MOS-B, MSU-SK, MSU-E, VISIR, Ozon-M, ALISSA)

ISTOK-1 (IR Spectroradiometric System)

ISTOK-1 is a sounder assembly. The objectives of the ISTOK-1 experiments are the development of the methods of ecological monitoring and meteorological sounding of the Earth: tests of the new types of spaceborne monitors, measurement geometry, simultaneous use of spectrometry and refractometry of the atmosphere. ¹⁷⁾

The ISTOK-1 apparatus consists of the following modules:

- Opto-Mechanical Block (OMB),

- Electronic Block of the IR-Spectrometer system (EBS),

- The data processing block (digital processing of video data),

- The computer block (built in Rumania)

Objective: Measurement of atmospheric irradiation for different observation angles.

- Vertical temperature profiles of the atmosphere (up to 30 km with an accuracy of 4 - 5 K) and its CO₂ band radiation.

- Altitude profile of pressure and temperature (with 0.2 km resolution).

- Humidity profiles from the measurement of the water vapor band (6.3 µm)

- Measurement of ozone content in the 9.6 µm band

- Measurement of ocean surface temperature

- Atmospheric chemistry

- Study of convective processes in the atmosphere

The IR-spectrometer, also referred to as MIRS (Multichannel Infrared Spectroradiometer), consists of two identical diffraction polychromatographs for the spectral ranges of 4 - 8 µm, and 8 - 16 µm.

- Number of spectral channels: 64

- Spectral resolution (bandwidth): 0.125 µm (4-8 µm region), 0.025 µm (8 - 16 µm region)

- Sensitivity: = 1 x 10 (W/cm/sr/m) for range 1; = 5 x 10 (W/cm/sr/m) for range 2

- Radiometric resolution: 14 bit

- Spatial resolution: 0.75 - 3 km (in flight direction)

- Look angles: -15º to 132º in orbit plane; 0º to 90º in azimuth plane

- Maximum rotation rate of instrument: 2.4 degrees/s

- Data rate: 10 kbit/s

VISIR (Visible Infrared TV-monitor and Atmospheric Refractometer)- a TV camera (part of the ISTOK-1 instrumentation) with the objective of surveying the region of measurement (clouds) with 256 x 256 pixels. Spectral ranges: 0.4 - 0.75 µm, look angle = 15º, spatial resolution = 300 m.

MSU-SK (Optical Multispectral Scanner)

MSU-SK is a moderate resolution instrument (heritage: from Meteor and Cosmos 1639, the sensor is being built by the Institute of Space Device Engineering, ISDE). MSU-SK measures in four channels of the visible spectrum: (0.5 to 0.6 µm, 0.6 to 0.7 µm, 0.7 to 0.8 µm, and 0.8 to 1.1 µm) with a resolution of about 120 m; MSU-SK also measures in the infrared spectrum (10.4 to 12.6 µm, TIR) with a resolution of about 400 m. The swath width is 320 km (at nominal altitude of 400 km).

- Look angle = 39º

- SNR for channel 1 = 70

- SNR for channels 2-5 = 100

- Noise level for channel 5 = 0.5 K

- Range of radio temperatures for channel 5 = 210 - 320 K (TIR)

- Data rate for channels 1-4 = 2.56 Mbit/s

- Data rate for channel 5 = 1.28 Mbit/s

MSU-E (Optical Multispectral Scanner)

MSU-E provides an electronic scanning method (CCD technology, built by ISDE). Measures in three visible channels (0.5 to 0.6 µm, 0.6 to 0.7 µm, and 0.8 to 0.9 µm); the resolution is 20 m; the average swath width is 2 x 27 km (two devices measure in parallel, one to each side of the ground track).

- Look angles: ±32º (the instrument may be pointed in the cross-range direction, thereby extending FOV to the Field of Regard (FOR)

- Radiometric resolution: 8 bit

- Data rate for each channel: 3.84 Mbit/s

Both scanners (MSU-SK and MSU-E) are operationally coupled (for instance: two channels may be switched on MSU-SK plus three channels on MSU-E).

MOS-P (Modular Optoelectronic Scanner - Priroda)

MOS is a passive pushbroom imaging spectrometer of medium spatial resolution for the visible and near-infrared spectrum (VNIR) of 0.4 - 1.01 µm. It is a nadir-viewing instrument, built by DLR/ISST, Berlin, Germany. MOS-P (also designation of MOS-OBSOR) is of MKS, and MKS-M heritage which were flown on Intercosmos-21, and the space stations Salyut-7 and Mir. Another version of MOS is flown on the ISRO mission IRS-P3. ^{18) 19) 20) 21)}

Objective: Image generation of the Earth's surface (surface-atmosphere interaction, ocean color, phytoplankton, regional and global distributions of aerosols and its links to gaseous admixtures, spectral and spatial cloudiness characteristics, etc.) in the VNIR region.

The sensor apparatus consists of two complementary instruments: MOS-A and MOS-B (see also Figure 7). MOS-A is a four-channel diffraction-scanner spectrometer, specialized for observing the atmosphere-ocean system in the O₂A absorption band around 760 nm. The objective is to estimate the aerosol optical thickness and stratospheric aerosols. - MOS-B is a 13-channel spectrometer in the range of 408 to 1010 nm. The center wavelengths of the channels are chosen with the objective for the quantitative retrieval of ocean an coastal zone parameters. They also provide a capability for vegetation signature determination (red edge) and estimation of H₂O (water vapor) content in the atmosphere from the NIR-measurements. An additional calibration mechanism permits the direct measurement of solar radiation.

Ozon-M

Ozon-M is a UV and IR eclipse spectrometer, a 4-band scanning diffraction spectrometer with an autonomous tracking system permitting sun occultation measurements. The objective is the measurement (sounding) of ozone concentrations and other trace gas elements in the atmosphere. The bands are: 0.26-0.3 µm (UV), 0.36-0.42 µm (UV), 0.6-0.7 µm (VIS), 0.91-1.05 µm (NIR). Russian sensor, organization: Integral.

ALISSA (l'Atmosphere par LIdar Sur SAliout)

ALISSA is a French sensor (Note: ALISSA did not fly on Salyut). ALISSA is conceived as a simplified fixed frequency lidar, using Mie scattering to detect clouds and aerosols. The primary objective is to study the impact of altitude determination on the description of the cloud field provided by geostationary satellites. Operation is during orbital night to minimize the difficulty of accurate system alignment. The main characteristics of the sensor are as follows: ²²⁾

Emitter:

- Second harmonic of Nd-Yag lasers: λ = 532 mm

- Energy pulse: 40 mJ

- Repetition rate: 50 Hz

- Natural divergence: 10^-3 rad

- Divergence after collimator: 10^-4 rad

Receiver:

- Cassegrain telescope of area A = 0.12 m²

- Field of view: 10^-3 rad

- Filter bandwidth: 0.5 nm

Energy requirements: 3 kW. The signal is analyzed by a pulse counting system with a gate of 1 µs, which provides a height resolution of: Δ_z = 150 m. The integration of six consecutive pulses (to increase the SNR) gives a horizontal resolution along the satellite track of: Δ_x,y = 1 km. The pulse counting system has 512 channels of 1 µs, which can be adjusted at 2, 4, 8 µs.

ALISSA science objectives:

- The cloud radiation problem: improving retrieval of large-scale cloud cover and cloud property data.

- The cloud radiation problem: interpreting small-scale structures of cloud tops

- Measurement of tropospheric aerosols and the boundary layer.

- Stratospheric studies.

MIRIAM (Mir Infrared Atmospheric Measurements)

MIRIAM is a sun occultation experiment for atmospheric trace gas spectroscopy. The instrument (German/Russian) was developed by the “Freie Universität, Berlin” (PI: R. Furrer) and by the St. Petersburg State University, St. Petersburg (PI: A. V. Poberovsky), Russia, using the FTIR (Fourier Transform Infrared) spectrometer technique (capable of sun radiation slant path IR absorption measurements during orbital sunsets) from satellites.^{23), 24) 25)}

The objective of MIRIAM is to gather long-term datasets (vertical profiles) of various trace gases, like: O_3, N₂O, CO, CH₄, NO, SO₂, NO₂, HNO₃, HF, HCl, NH₃, OCS, HCN, CH₃Cl, C₂H₂, H₂O, HBr, ClO, HOCl, H₂O₂, OH, H₂CO, C₂H₆, etc.

The FTIR-spectrometer is mounted outside the Priroda module in a hermetic (N₂-pressurized) container. Solar radiation enters the spectrometer via an active suntracker and a telescope. The light passing the beamsplitter (potassium bromide) separates into two beams prior to entering the retro-reflector arrays. The amplified detector signal is noise-filtered before A/D conversion (14 bit resolution). Prior to Fourier transformation the signal biases are removed; the interferograms are apodized with a Hamming window.

MOMS-2P (Modular Optoelectronic Multispectral/Stereo Scanner - 2 Priroda)

Mission context: MOMS-2P is a German imaging instrument on Priroda, a module of the Russian Mir space station. Part of the MOMS-2P instrument (the optical module, which is mounted on the outside of Priroda) was launched by a Progress M-31 launch vehicle on May 5, 1996 (docking of Progress at Mir on May 7, 1996). The Progress launch was a regular service flight to MIR, it was preceded by the Priroda launch on a Proton vehicle on April 23, 1996.

MOMS-2P on Priroda is a modified MOMS-02 (of D2 Shuttle mission heritage) instrument featuring an additional integrated navigation package (GPS receiver + Gyro), referred to as MOMSNAV (MOMS Navigation) for more accurate attitude and orbit determination, hence ground positioning of the data. MOMS-2P is a DLR instrument, sponsored by DARA, built by EADS Astrium (former DASA/DSS) and by Kayser Threde GmbH (MOMSNAV). Portions of the MOMS-2P (camera system) and the MOMSNAV package (two GPS antennas, two redundant gyro sensor blocks, one gyro electronics unit) are mounted onto the outside of the Priroda module. MOMS-2P is being operated from DLR/GSOC via ZUP, Moscow. ^{26) 27) 28) 29) 30) 31) 32) 33)}

MOMS-2P is a modular instrument with a total of five optical systems: three are dedicated for stereoscopic imagery, two are employed for multispectral imagery, one (central lens) is used for high-resolution data. Two linear CCD (Charge-Coupled Device) arrays are optically combined in the focal plane of the center lens in order to obtain a sufficiently wide swath. Along-track stereo imagery is obtained with the center lens (ch. 5) and two tilted (forward and backward) lenses (ch. 6 and ch.7). The focal length of the tilted lenses was chosen in such a way as to obtain an integral relationship between the ground pixel sizes seen by the center lens and the two tilted lenses; this ratio is 1:3. Each of two MS lenses (ch. 1,2,3,4) also optically combine two linear CCD arrays in the focal plane for a wider swath. Data quantization: 8 bit with seven gain steps [uncompressed for MS and stereo, 6 bit compressed for stereo and HR (High Resolution) data]. Each CCD array features 6000 elements (10 µm per element).

MOMS-2P operations are limited by the data rate of the onboard tape recorder of 100 Mbit/s. It implies that all channels cannot be operated simultaneously. A set of four operational modes are defined combining different channels for various applications. Table 10 summarizes the four modes with the corresponding numbers of pixels per imaging line. The tape recorder allows a maximum tape capacity of 48 GByte corresponding to a recording time of 80 minutes for an average data rate of 10 MByte/s.

The MOMS-2P objectives cover applications in the fields of photogrammetry, land cover, geomorphology, ecology, basic research in the spectral signatures of rocks, soil, vegetation, etc. The following capabilities are provided:

• Three-line linear stereo imagery of high spatial resolution and pointing accuracy

• Along-track stereo capability in panchromatic or in defined multispectral (MS) modes

• Detection of surface materials by optimized position bands and detection of small-scale textures of the Earth's surface.

The MOMS-2P instrument is being operated by means of timelines stored onboard the Priroda module. Mission planning selects target areas for imaging along with all information required for execution. A set of four operation modes have been defined, combing different channels to be selected for various applications. The following modes are being operated during the mission:

Mode A: Bands 5a, 5b, 6, and 7 allow for the calculation of three-band stereo models, i.e. high precision DTM (full stereo mode).

Mode B: Bands 1, 2, 3, and 4 in various combinations as color composites as well as digital data serve as base for thematic applications like classification relative to lithology, pedology, vegetation etc. (full spectral mode).

Mode C: Bands 2, 3, 4, and 5a fulfil the requirements for the generation of various standard image processing products by use of the three spectral bands, the additional application of the high resolution panchromatic band, and consideration of suitable algorithms (multispectral channel plus HR nadir channel).

Mode D: Makes use of 2 multispectral channels plus two stereo channels (channels 1,4,6,7). It permits DTM generation and thematic applications.

The MOMS-2P source data (along with housekeeping and navigation data) are recorded onto an onboard tape recorder and are transmitted to a ground receiving station (DFD Neustrelitz) during overpasses.

Other MOMS-2P observation restrictions are due to energy budget limitations of the Mir station and/or particular Mir orientations unsuitable for remote sensing.

MOMS-2P Calibration

Geometric calibration. Refers to the generation of exact object side angles for a precise photogrammetric three-dimensional reconstruction of the Earth's surface (considering all geometric scanner influences such as irregularities of the CCD arrays, bending of the focal planes, optical distortions, etc.). Geometric inflight calibrations are performed on a set of precisely known ground targets in conjunction with navigation data (MOMSNAV). The Catalonia test site in Spain is being used (several times per month) during the commissioning phase. ³⁴⁾

Radiometric calibration. This method employs a set of ground targets with known spectral signatures.

Sun calibration. The cover of the MOMS-2P camera is coated on the inside with a diffuse reflecting coating. When opening the cover it can be locked at an angle of 20º. A sun calibration is performed by pointing this cover toward the sun. The measurements obtained are compared with data from inflight calibration for reasons of verification.

MOMSNAV (MOMS Navigation). An integrated navigation package built by Kayser-Threde (Munich) with the objective to provide accurate location knowledge to MOMS-2P imagery. MOMSNAV is a DGPS-based navigation package consisting of the following elements: two GPS antennas, two redundant gyro sensor blocks, one gyro electronic unit, and an electronic box. The instrument provides navigation data which is used in post-processing in combination with the image data. MOMSNAV location knowledge accuracy of the imagery is ≤5 m horizontal (1σ), the relative attitude accuracy is ≤10 arcseconds (1σ). Instrument mass = 41 kg, power = 70 W (average). ³⁵⁾

Data Distribution: Priroda has six onboard data recorders with a capacity 6 Gbit each. One recorder is used for the recording of SAR data, four recorders are used for all other data, one recorder is in reserve. Priroda sensor data are transmitted to two ground stations, one at RKK Energia in Obninsk, the other at DLR/DFD Neustrelitz, Germany. RKK Energia preprocesses all sensor data and provides all required ancillary data. The time delay for preprocessing is currently projected for about 1 week after data reception.

Agreements relating to data sharing have been concluded between IRE and its partners (the sensor providers and countries participating in the Priroda mission) who have primary access to all science data and ancillary information. MOS-OBSOR and MOMS-2P sensor data is being processed and archived by DLR/DFD Neustrelitz as the responsible data center for all German users. Thematic processing may be done at the user sites (SAR Travers data calibration is being planned at DLR in Oberpfaffenhofen). Data transfer from Moscow to Germany may be provided via suitable transportable storage media (Exabyte) or via Eutelsat satellite communication.

Earth observation instruments on the Russian Space Station Mir

The Table 13 is an attempt to list the Earth observation instruments flown on the Mir station. Unfortunately there was only very scant documentation to work from. ^{37) 38)}

References

1) http://www.energia.ru/english/energia/mir/mir-structure.html

2) “Complex for Remote Sensing of the Earth,” Science Program, DLR paper 1991

3) “Mir Space Station - Mir Modules,” NASA, URL: http://spaceflight.nasa.gov/history/shuttle-mir/spacecraft/to-s-mir-mod-main.htm

4) http://www.russianspaceweb.com/mir.html

5) http://www.pbs.org/safarchive/5_cool/5_mir/mir5.html

6) N. A. Robinson, “Perestroika and Priroda: Environmental Protection in the USSR,” 1988, URL: http://digitalcommons.pace.edu/cgi/viewcontent.cgi?article=1384&context=lawfaculty

7) http://www.astronautix.com/craft/mirmplex.htm

8) http://www.astronautix.com/craft/priroda.htm

9) “The Shuttle/Mir Program,” URL:  https://web.archive.org/web/20141008064025/http://www.satobs.org/mir-shuttle.html

10) http://www.hq.nasa.gov/office/budget/fy96/hsf_2.html

11) Orbital Station Mir, Complex of Remote Sensing of the Earth “Priroda,” Scientific Program, IRE brochure, Moscow, 1991

12) http://en.wikipedia.org/wiki/Priroda

13) G. H. Kitmacher, “Development, Integration and Operation of Systems of the Priroda Module,” Proceedings of the IAC 2002 (International Astronomical Congress, Houston, TX, USA, Oct. 10-19, 2002, IAC-02-T.P.O1, URL: http://www.spacearchitect.org/pubs/IAC-02-T.P.01.pdf

14) G. Zimmermann, “Mission Priroda,” German Proposals to Scientific Program, DARA Bulletin, Dec. 1991

15) T. J. Jackson, A. Y. Hsu, N. Armand, B. Kutuza, A. Shutko, Yu. Tishchenko, B. Petrenko, A. Evtushenko, “Priroda passive microwave observations in the Southern Great Plains1997 Hydrology Experiment,” Proceedings of IGARSS'98, Volume 3, Issue , July 6-10, 1998, Seattle, WA, USA, pp.1568-1570

16) I. V. Bragin, V. P. Sgibnew, K. A. Pobedonostsev, A. V. Evtushenko, B. N. Savin, A. A.. Morozov, V. F. Mikhailov, S. I. Bragin, Y. B. Bragina, N. S. Maslova, M. B. Kamenkov, I. A. Zheltikov, G. M. Kolner, “Space-Based Remote Sensing Complexes,” Proceedings of the 29th European Microwave Conference, Munich, Germany, Oct. 5-7, 1999, Vol. 2, pp. 388-390

17) B. V. Dementiev, V. V. Ivanov, S. G. Kukin, Yu. S. Ivanov, A. Y. Silyakov, A. D. Chikin, N. V. Shilin, M. Maly, V. Jirka, P. Orleansky, M. Michalska, O. Maris, L. Shtefanov, R. A. Sargsyan, S. H. Babayan, V. A. Panchenko, “Infrared spectroradiometric system ISTOK-1 of the MIR orbital station,” Proceedings of SPIE, 'Current Russian Research in Optics and Photonics: New Methods and Instruments for Space- and Earth-based Spectroscopy in XUV, UV, IR, and Millimeter Waves,' Igor I. Sobelman; Vladimir A. Slemzin; Eds., Vol. 3406, 1998 pp. 119-134

18) A. Neumann, “Spaceborne Imaging Spectrometers for Ocean Color Remote Sensing, MOS-Priroda and MOS-IRS,” DLR/ISST paper presented at the IOC Ocean Color Workshop, Victoria, BC, September 21-22, 1995

19) http://www.dlr.de/os/desktopdefault.aspx/tabid-3489/5374_read-7987/

20) P. Cipollini, G. Corsini, “Modular optoelectronic scanner (MOS): a study of its capabilities for optically active parameter estimation by means of an ocean color model,” Proceedings of SPIE, Vol. 2963, February 6, 1997, p p. 648-653, ISBN: 9780819423672, Ocean Optics XIII, Steven G. Ackleson; Ed.

21) Gerhard Zimmermann, Andreas Neumann, Karl-Heinz Suemnich, Horst H. Schwarzer, “MOS/PRIRODA: an imaging VIS/NIR spectrometer for ocean remote sensing,”Proceedings of SPIE, Vol. 1937, April 14, 1993, Orlando, FL, USA, 'Imaging Spectrometry of the Terrestrial Environment,' Gregg Vane, Ed.

22) M. L. Chanin, M. Desbois, A. Hauchecorne, “ALISSA a French Russian cooperation in the Priroda mission.” Paper of CNRS - Service d'Aeronomie

23) R. Furrer, H. Rubin, M. Schaale, A. V. Poberovsky, A. V. Mironenkov, Y. M. Timofeyev, “MIRIAM - A Spaceborne Sun Occultation Experiment for Atmospheric Trace Gas Spectroscopy,” GeoJournal 32.1, January 1994, pp. 17-27

24) “MIRIAM 1995-1998 Mir-Infrared Atmospheric Measurements - Untersuchung der Atmosphäre aus der Raumstation Mir,” Institut für Weltraumwissenschaften an der Freien Universität Berlin, 1994

25) R. Furrer, V. V. Antonov, Y. M. Timofeyev, “FTIR-spectroscopy from space - The MIRIAM mission (Mir Space Station Infrared Atmosperic Measurement),” Advances in Space Research (ISSN 0273-1177), Vol. 15, No. 11, 1995, pp. 135-144.

26) Manfred Lehner, Wolfgang Kornus, “Band-to-Band Registration for the German Pushbroom Scanner MOMS-2P,” ISRPS Workshop on 'Sensors and Mapping from Space', September 27-30, 1999, Hannover, Germany, URL: http://www.ipi.uni-hannover.de/fileadmin/institut/pdf/lehner_01.pdf

27) German User Requirements to Priroda Mission, Annex 1 of Protocol to MOMS-2 for the Priroda Mission, DLR paper of Priroda Workshop, May 1991

28) Protocol of the Meeting of Specialists of USSR and Germany on MOMS-2 for the Priroda Mission. DLR paper, May 1991

29) D. Meißner, et. al., “The MOMS-2P Instrument and its Mission on Priroda/Mir Station,” IAF-96-B.4.03, 47th International Astronautical Congress, Oct. 7-11, 1996, Beijing, China

30) DASA Endbericht, “MOMS-02P auf Priroda/Mir,” Doc. No. M2P-DAS-100-RP-001.0, Dec. 12, 1996

31) D. Meissner, G. Lichtenauer, S. Föckersperger, F. Claasen, “The MOMS-2P instrument and its mission on PRIRODA/MIR station,” Acta Astronautica, Vol. 44, Issues 5-6, March 1999, pp. 293-301

32) P. Seige, P. Reinartz, M. Schroeder, “The MOMS-2P Mission on the MIR Station," International Archives of Photogrammetry and Remote Sensing, Vol.XXXII, Commission I Symposium, pp. 204-210, Bangalore, India, 1998

33) “MOMS-2P,” 2011, URL: http://www.hufenbecher.de/moms.htm

34) Wolfgang Kornus, Manfred Lehner, Manfred Schroeder, “Geometric Inflight Calibration by block adjustment using MOMS-2P imageryof three intersecting stereo-strips,” ISPRS Workshop on ’Sensors and Mapping from Space 1999’, September 27-30, 1999, Hannover, Germany, URL: http://www.ipi.uni-hannover.de/fileadmin/institut/pdf/kornus_2_.pdf

35) S. Föckersperger, et al., “MOMSNAV: Location of the Russian Space Station Mir with Differential GPS,” Proceedings of the 2nd ESA International Conference on GNC, ESTEC, 12-15 April 1994, pp. 159-165

36) IKAR-D, -P and MSU-SK with forward look angle (in flight direction) of 40º against nadir

37) Overview paper provided by G. Zimmermann of DLR (IKF) Berlin, Aug. 1991

38) MIR Earth Images are sold by `Energia Deutschland GmbH', a joint venture of NPO Energia, Moscow and Kayser-Threde of Munich, Germany - see Space News, Aug. 17-23, 1992, p. 13

The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (eoportal@symbios.space).