Space studies

Academician V.E. Zuev, the founder of the Institute of Atmospheric Optics, formulated its basic research fields so that they included practically all possible aspects concerning the interaction of optical radiation with the atmosphere and thorough atmospheric studies, in particular from space, and remote sensing of the Earth from satellites.
 

BALKAN First Russian Spaceborne Lidar

Prototype of BALKAN lidar

The BALKAN (onBoard Aerosol Lidar of the Academy of Sciences) lidar was the first Russian instrument for laser sensing of the atmosphere from space., In 1984, NPO Energia (Russian Space Corporation) initiated development of new research instrumentation for MIR multifunctional orbital station. BALKAN was developed and manufactured by three organizations: IAO SB RAS as a head organization, Optika Design Bureau (now IMCES SB RAS), and the Russian Research Institute of Space Instrumentation (Moscow)In 1990, all ground tests were completed, and the lidar was ready for launching into space as part of the Spektr module of MIR station. Academician V.E. Zuev announced creation of the first Russian space lidar at the XV International Lidar Conference held by the Institute of Atmospheric Optics in Tomsk in July 1990.   

Lidar transceiver

The transformation and following collapse of the USSR and, as a result, the lack of funding delayed the launch of the Spektr module as a whole. It was mothballed, and only in May 1995, after new prelaunch tests, the lidar was in near-earth orbit. Measurements with the BALKAN space lidar were carried out in 1995–1996 by during three orbiting missions. In June 1996, due to an off-site accident at the Spektr module, the works with the BALKAN lidar were stopped, although it used less than 10% of its resource.

Experiments to refine the technique of orbital laser sensing and to test algorithms for interpretation of lidar signals were continued with the ALISSA Russian-French lidar as a part of the Priroda module of MIR station orbited from mid-1996.
BALKAN was successfully operated for sensing the ground surface and the upper ocean layer, measuring cloud parameters on the global scale, and validating the orbital parameters of the MIR station by the lidar method. BALKAN results allowed technological verification of lidars and development of techniques for joint subsatellite experiments. In addition, arrays of lidar signals for testing lidar data processing algorithms were obtained.

Reference:

Balin Yu. S., Tikhomirov A. A. The history of development and operaion of the first Russian space lidar BALKAN integrated into Mir space station . // Optika Atmosfery i Okeana. 2011. V. 24. No. 12. P. 1078-1087 [in Russian].
 

Receiving and thematic processing of satellite images

Satellite  image  of  wildfire  hotspots

The group (later, laboratory) for spaceborne sensing was organized in the IAO SB RAS as early as 1981. The laboratory dealt with complex integrated research aimed at calibration of Russian optoelectronic devices for remote sensing of the Earth’s surface from space. The task formulated by the USSR space department was to "teach" devices to convert optical radiation parameters measured in space into quantitative characteristics of the Earth's surface (for example, temperature) with high accuracy.
 

Filtering  of  satellite  images

Unfortunately, with the collapse of the USSR, the works on the creation and operation of satellite constellations forming the Earth remote sensing system were curtailed. At the same time, foreign satellite data turned out to be unavailable. However, the IAO SB RAS did not stop the research aimed at the use of satellite data for studying and monitoring characteristics of the atmosphere and the earth's surface. V.E. Zuev addressed a proposal to the Academy of Sciences, and it allocated funds for acquisition of the ScanEx station for receiving information from NOAA meteorological satellites (USA). Since 1987, the IAO SB RAS receives satellite data, processes them, and applies for practical needs. In 2011, through the Instrument Commission of the Russian Academy of Sciences, the IAO SB RAS received the new station for receiving satellite data (Model 2.4 XLSA SYSTEM) made in the USA.


Western Siberiasatellite  image

One of the most important tasks of the IAO SB RAS is developing the software for atmospheric correction of space images for numerous applied problems, such as obtaining data on the temperature of the Earth’s surface needed for meteorological and climate studies, early detection of emergencies and natural disasters such as wildfires and floods (the efficiency of the IAO SB RAS algorithm for hotspot detection algorithms is higher than that of foreign analogs), monitoring of the state of agricultural crops occupying vast territories, and recognition of objects on the Earth's surface by studying their reflective properties. The hotspot detection algorithms have been successfully used for more than ten years to monitor fire hazardous situations in the Tomsk region.
Since 2017, by order of the Russian Space Agency, the IAO SB RAS has been creating the software for atmospheric correction of images of the Earth's surface obtained from the reviving Russian satellite remote sensing system.
In 2020, the software for atmospheric correction in the visible and near-IR ranges was developed for arbitrary optical-geometric situations and underlying surfaces. It is used for thematic processing of images of Terra and Aqua satellites (USA) and Russian Resurs-P and Meteor-M satellites.  

Reference:

Belov V.V., Tarasenkov M.V., Engel M.V., Gridnev Yu.V., Zimovaya A.V., Abramochkin V.N., Poznakharev E.S., Fedosov A.V. and Kudryavtsev A.N. Atmospheric Correction of Satellite Images of the Earth’s Surface in the Optical Wavelength Range. Optical Communication Based on Scattered Radiation // Atmospheric and Oceanic Optics, 2020, V. 33. No. 01. pp. 80–84.

Systems for measuring astroclimatic and meteorological parameters

Uninterrupted operation of the network of quantum-optic systems (QOS) is necessary to ensure the successful operation of the Russian Space Surveillance System. Specialized devices being a part of QOS are used for continuous monitoring of spacecraft and space debris. In potentially dangerous situations, the trajectories of satellites can be changed. For operation of surveillance systems, the conditions of visibility through the atmosphere should be determined in real time. For this purpose, the IAO SB RAS has developed and assembled unique hardware-software systems, whose modifications were installed in Altay, Moscow Region, Shchelkovo, and the Caucasus.

Moscow Region

Altay

Caucasus

The IAO SB RAS operates TomSky panoramic-optical station for round-the-clock monitoring of the optical state of the sky. Methods and technical facilities for real-time remote determination of optical and physical parameters of atmospheric objects, such as clouds, smoke, and aerosol formations are developed. In addition, these methods and instrumentation can be used for determination of similar parameters of any other objects both inside and outside the atmosphere.

When launching spacecraft, it is necessary to have objective and independent information about the spacecraft state, parameters of its trajectory and speed at all stages of spacecraft acceleration, the state of cloudiness and its dynamic properties near the launch site and along the entire flight path. The hardware system operation is based on photometric observations of brightness of optical radiation scattered from objects and photogrammetric observations of the objects (rockets at the acceleration section of the route, aircraft, clouds, smoke, aerosol layers) located both inside and outside the atmosphere at slant paths of various lengths. As a result, the following problems are solved: real-time determination of the trajectory parameters of objects in the earth's atmosphere at ranges from 0.5 km to 1000 km, estimation of their dimensions and brightness, and online space-time forecast of the location of moving objects.

Reference:

Matvienko G.G., Babushkin P.A., Bobrovnikov S.M., Borovoi A.G., Bochkovskii D.A., Galileiskii V.P., Grishin A.I., Dolgii S.I., Elizarov A.I., Kokarev D.V., Konoshonkin A.V., Kryuchkov A.V., Kustova N.V., Nevzorov A.V., Marichev V.N., Morozov A.M., Oshlakov V.K., Romanovskii O.A., Sukhanov A.Ya., Trifonov D.A., Yakovlev S.V., Sadovnikov S.A., Nevzorov A.A. and Kharchenko O.V. Laser and Optical Sounding of the Atmosphere // Atmospheric and Oceanic Optics, 2020, V. 33. No. 01. pp. 51–68. 
 

Molecular spectra as a key to undestanding the nature of exoplanets 

Molecular spectra are a kind of key to understanding the processes taking place in the atmospheres of the Earth and other planets of the Solar System, as well as exoplanets. The calculation of molecular spectra, including high-temperature one, requires voluminous computing resources. High-temperature spectra are studied with method of quantum chemistry. One of the research fields is calculation of molecular spectra of methane, which is one of the indicators of life on a particular planet, including exoplanets. High-temperature spectra of many molecules are calculated by the IAO SB RAS.

For many years, the IAO SB RAS collaborates with colleagues from the universities of Paris, Reims, and Grenoble (France), Harvard University and the National Aeronautics and Space Administration (NASA, USA), as well as with scientific laboratories in China and Japan.

Spectral studies are of great fundamental importance and have numerous practical applications. For example, high-accuracy data on spectra of methane and carbon dioxide are needed to our Japanese partners, who launched a spectrometer into the near space within the framework of the GOSAT (Green House Gases Observing Satellite) Project. With the use of our computed data and findings of the orbital scanning spectrometer, it is possible to retrieve efficiently the concentration of methane, carbon dioxide, and other greenhouse gases in the Earth’s atmosphere. New promising fields include calculation of spectra of complex five- and eight-atomic molecules (for example, ethylene molecule) present in the atmosphere of the Earth and other planets.

The internet bank of spectral line parameters of the carbon dioxide, which is the main component of the atmospheres of Venus and Mars, is created and permanently updated. This bank is actively used by Roskosmos, NASA, and European Space Agency.

CO2 absorption spectra at different temperatures

Water vapor plays a huge role in the human life on the Earth, and takes part in formation of the cloudy layer in the atmosphere of Venus, and has a significant impact on climatic processes on Mars. The spectra of water vapor are actively studied in the IAO SB RAS.

In cooperation with the Space Research Institute RAS, the IAO SB RAS obtained significant results concerning the description of spectra of the so-called heavy water, which make it possible to obtain new data on the atmospheres of Mars and Venus. Scientists are interested in the atmosphere of Mars. If sulfur containing gases (hydrogen sulfide, sulfur oxides) are found there, then the hypothesis of continuing geological and volcanic activity on this planet will be confirmed. It should be noted than methane was not found in the Martian atmosphere, but the carbon dioxide magnetic dipole absorption band was observed for the first time.

First observation of the magnetic dipole CO2 band in the Martian atmosphere.  
Spectrum of the Martian atmosphere recorded by ExoMars (black curve) and simulated with HITRAN (blue curve).  B: Magnetic dipole ν2 + ν3 band of CO2 (difference between the recorded and simulated spectra) 

 

 
Reference

Perevalov V.I., Ponomarev Yu.N., Ptashnik I.V. and Sinitsa L.N. High-Resolution Molecular Spectroscopy at the Institute of Atmospheric Optics: Current Status of Theoretical and Experimental Research // Atmospheric and Oceanic Optics, 2020, V. 33. No. 01. pp. 10–26. 
 

Cloudiness: processing of satellite data

The data on the global cloud field obtained with satellite systems have a wide range of application. They are needed for weather forecasting, climate models, and aircraft flight safety. В Since 2009, the IAO SB RAS has been developing unique computer software that automatically determines different types of cloud fields. The studies are carried out at the intersection of atmospheric optics, programming and high-precision image processing. Special programs capable of processing a huge array of high-precision cloud images obtained by remote sensing systems from space are being developed. This allows studying various regions, in which territory there are no ground-based weather stations. The first step was to create a special database of typical cloud images. The next step was machine learning to classify clouds by texture characteristics: in the automatic mode, the computer gives an answer to the question of what type a cloud belongs to, for example, whether it is cirrus or cumulus. The software operation is based on the analysis of brightness differences in a fragment of a satellite image of cloudiness..

Original algorithms for classifying clouds based on satellite data by artificial intelligence methods have been developed. They allow distinguishing not only the main cloud types, but also their subtypes and some combinations at any time of the day. In the daytime and at night,15 and 13 cloud types can be recognized, respectively, with a probability of 0.85. To describe clouds, textural features of space images in the visible spectral range and their physical characteristics, are used. A probabilistic neural network is used as a classifier. The algorithms are implemented with the parallel computing technology on general-purpose graphics processors. The figures show the result of cloudiness classification over Western Siberia based on the MODIS satellite image obtained in the daytime.

The algorithm for recognizing 5 types of atmospheric fronts from space data of remote sensing of the Earth by artificial intelligence methods has been developed. It consists essentially in using the results of cloud classification to search for sequences of cloud types characteristic of each type of atmospheric front. Information on the water content of clouds and temperature and pressure at the surface level is used. The algorithm allows distinguishing warm, cold type 1, cold type 2, occluding as warm, and occluding as cold atmospheric fronts.

MODIS satellite image

Result of cloud classification on a satellite image 

Cloud mosaic

References:
  1. Astafurov V.G., Skorokhodov A.V., Kur’yanovich K.V. and Mitrofanenko Ya.K. Parameters of Different Cloud Types over the Natural Zones of Western Siberia According to MODIS Satellite Data // Atmospheric and Oceanic Optics, 2020, V. 33. No. 05. pp. 512–518. 
  2. A.V. Skorokhodov, K.V. Kuryanovich A study of variability characteristics of atmospheric internal waves over the Russian Federation Pacific coast // SOVREMENNYE PROBLEMY DISTANTSIONNOGO ZONDIROVANIYA ZEMLI IZ KOSMOSA (CURRENT PROBLEMS IN REMOTE SENSING OF THE EARTH FROM SPACE). 2019. V. 16. No. 6. PP. 245–253. 

Determination of light pressure on the mesh of satellite antenna reflectors

In 2017-2018,  scientists of the Institute of Atmospheric Optics have studied the light pressure on structural materials with an experimental setup based on the Bruker Optics IFS 125 HR Fourier spectrometer. This setup allows measuring the intensity of radiation incident, scattered, absorbed, and transmitted by a material under study in the entire solar spectral range. The knowledge of the light pressure on the mesh of satellite antennas is important for planning the necessary fuel supply for the long-term orbiting of a satellite. The lighting characteristics (transmission and reflection coefficient) of the structural materials have been measured. The mathematical model of solar irradiation of the structural material at any angle was constructed and verified experimentally. The effect of the light pressure on the structural materials was calculated Samples of satellite antenna mesh were used as the structural material. The pressure of solar radiation on the satellite antenna mesh was determined through precision measurement of the full scattering phase function on a sample. The scattering phase function was found from about 2000 of single measurements of radiation scattered by different mesh samples for different angles of radiation incidence and from calculation of the scattering phase function for large incidence and scattering angles based on the 3D geometric-optics model.

Bruker Optics IFS 125 HR Fourier spectrometer

Satellite antenna mesh

 

Space lidar project

One of the interesting problems solved in IAO SB RAS is precision landing of descent spacecraft. Calculating the descent trajectory and coordinates of landing spacecraft is a complex multi-parameter problem. Sometimes the actual and the calculated landing points are spaced by tens of kilometers and more, even for the ballistic descent mode of a spacecraft. When braking in the atmosphere, the spacecraft speed and direction depend on the air density, temperature, and composition, as well as wind speed and many other atmospheric parameters. The accuracy of predicting the spacecraft landing site determines the course and duration of a search operation. Coordinates of the landing site are determined with the actual value of atmospheric density in the column of 15 to 100 km. At the Small Station for High-Altitude Sensing of IAO SB RAS, investigators determine remotely the aerosol concentration, atmospheric temperature, and density from lidar data. This will allow real-time measurement of atmospheric parameters a few hours before spacecraft de-orbiting due to development of a special-purpose lidar system to be installed onboard the International Space Station.

Receiving telescope

Laser transmitter

References:
  1. Marichev V. N. The analysis of the air density and temperature behaviour in the stratosphere above Tomsk in periods of perturbed and quiet states performed according to the results of lidar measurements . // Optika Atmosfery i Okeana. 2013. V. 26. No. 09. P. 783-792 [in Russian].
  2. Matvienko G.G., Babushkin P.A., Bobrovnikov S.M., Borovoi A.G., Bochkovskii D.A., Galileiskii V.P., Grishin A.I., Dolgii S.I., Elizarov A.I., Kokarev D.V., Konoshonkin A.V., Kryuchkov A.V., Kustova N.V., Nevzorov A.V., Marichev V.N., Morozov A.M., Oshlakov V.K., Romanovskii O.A., Sukhanov A.Ya., Trifonov D.A., Yakovlev S.V., Sadovnikov S.A., Nevzorov A.A. and Kharchenko O.V. Laser and Optical Sounding of the Atmosphere // Atmospheric and Oceanic Optics, 2020, V. 33. No. 01. pp. 51–68. DOI: 10.15372/AOO2010906.

Study of ice clouds from satellites

IAO SB RAS (Tomsk, Russia) cooperates with the Kyushu University (Japan) on the topic "Study of the Earth's ice clouds from the EarthCARE satellite”. EarthCARE (Earth Cloud Aerosol and Radiation Explorer) satellite equipped with lidar and radar is planned for launch in June 2022 as a joint mission of the Japanese Aerospace Exploration Agency (JAXA) and European Space Agency (ESA). As a result, the unique databank on cirrus cloud backscatter matrices for different shapes and sizes of ice crystals has been compiled. This databank allows calculating lidar and radar signals when sensing ice clouds from EarthCARE satellite and retrieving the shape and size of ice crystals that are needed in numerical models for forecasting the local weather and global climate. The possibility of retrieving the crystal shape from the measured lidar ratio at 355 and 532 nm and depolarization ratio is demonstrated..

Reference:

Okamoto H., Sato K., Borovoi A., Ishimoto H., Masuda K., Konoshonkin A., and Kustova N. Wavelength dependence of ice cloud backscatter properties for space-borne polarization lidar applications // Opt. Express. 2020. V. 28. No. 20. P. 29178-29191. DOI: 10.1364/OE.400510.