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We propose a calculation procedure for obtaining multispectral images in remote sensing of vegetation objects in the spectral range 400-1000 nm, based on three-channel spectral zonal images and reference spectra measured at several points of the recorded scene. The procedure makes it possible to improve the information content of the data for solving various thematic classification problems.Introduction. Differences in the reflectance spectra of objects is the basis for recognition of such objects by optical remote sensing [1][2][3][4][5]. In studies of the Earth's vegetative cover, in particular forests, the possibilities of remote sensing have been far from completely utilized [6,7]. Most work on remote sensing as applied to forests (as for other vegetation stands) is based on data obtained from space vehicles. In a number of publications, the authors rely on data obtained using spectrometers and video spectrometers mounted on airplanes [8][9][10][11] and also on helicopters [7]. The advantages and disadvantages of airborne imaging from aircraft are briefly discussed in [5,7]. In addition, we note that when aircraft are used, the reliability of the classification of types of stands may be very high. Comparison of the results from using images with different spatial resolution [12] showed that images obtained from low altitudes make it possible to determine forest fragmentation and biodiversity at the level of individual treetops (for inventory purposes), while those obtained from high altitudes make it possible to very accurately classify the composition of the vegetation at the landscape level. One more problem in forest monitoring which is also solved more accurately using aircraft is determination and assessment of damage done by forest fires. This problem is important not only from an economic point of view but also from the standpoint of the effect of fires on global ecology, which is more significant than suggested in [13].An advantage of spectral zonal images obtained on board aircraft is their high spatial resolution, generally matching the rather large dimensions of the frame (capture band); a relative disadvantage is the limited set of spectral zones (bands), which may not always convey the specific spectral details of objects on the underlying surface. However, very often three or four channels are enough to achieve good recognition of vegetation [14]. In this case, in contrast to automatic classification based on the spectral characteristics of the image recorded by a hyperspectral camera, here partially interactive processing is required to ensure high accuracy [15, 16]. The correct choice of the channels optimizes the spectral zonal system with respect to the efficiency/cost criterion and is quite important. This choice depends on the objects to be studied (the underlying surfaces) and what needs to be done. The video spectrometric system VSK-2 that we designed and used for studying forests [5,7] is an imageplane scanner. Each frame records "instantaneously"; in contrast to hyperspectral scanners,...

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We present energy calculations for the basic parameters of a spectrophotometric system designed for recording the vertical distributions of the spectral brightness of hydroxyl airglow and the brightness of airglow from the green line of atomic oxygen in the upper layer of the Earth's atmosphere. We consider the scheme for conducting the "Hydroxyl" space experiment with instrumentation in the spectrophotometric system and methods for measuring the brightnesses of the indicated airglow components in sessions for observation of the Earth's night upper atmosphere in the altitude range 80-110 km from on board the International Space Station (ISS).Introduction. The optical glow of the atmosphere represents luminescence of atmospheric components at altitudes of 80-300 km and includes both individual emission lines and bands as well as a continuum. The hydroxyl (OH) emission bands make the largest contribution to the total energy of the airglow. Together with the continuum, they make up ≈87% of the total energy of the airglow. The contribution from the green line of atomic oxygen (OI) at 557.7 nm is ≈10%. ≈3 of the glow energy comes from the red line of oxygen at 630.0 nm, the sodium line, and lines for all the rest of the gases. The specifics of generation of the emissions from vibrational-rotational bands of OH and the 557.7 nm line of oxygen determines their high sensitivity to changes in the temperature and composition of the atmosphere. This airglow is used to determine the temperature and concentration of small gaseous components of the mesosphere, to study the dynamics of aeronomic processes and chemical kinetics at mesospheric temperatures, the nature of internal gravitational waves, for prediction of possible earthquakes from observed airglow variations. The latter application is the one of most practical importance.The characteristics of night airglow in the 557.7 nm and 630.0 nm oxygen lines, the sodium 589.0 nm, 589.6 nm lines, and the hydroxyl OH (8-3) bands were analyzed in connection with seismic activity in [1][2][3][4]. It was shown that during the "preparation" period and development of earthquakes, perturbations are observed in the indicated emissions on different time scales. In particular, for the OI 557.7 nm line, a substantial increase in the glow intensity was established within 1-2 days before an earthquake [3,4], with an abrupt decrease in the days following an earthquake.Despite the great practical importance and 50 years of research history, the mechanism of hydroxyl airglow still has not yet been quantitatively explained. Conducting experiments under space conditions with measurement of the vertical profiles of OH(v) and O( 3 P) airglow radiance followed by determination of the OH(v, J) populations and O( 3 P) concentrations will make it possible to refine the mechanisms of the processes and rate constants of reactions determining these airglow components and thus to make remote measurements of atmospheric parameters more reliable for practical purposes.In the A. N.

Описуються вимірювання і оптимізація поля зору спектрометричного модуля фотоспектральної системи, що використовується на борту міжнародної космічної станції в рамках космічного експерименту «Ураган». Розглянуто модифіковану оптичну схему із зменшеним полем зору модуля спектрорадіометра в сагітальній площині, а також результати відносної прив'язки цього поля до поля зору модуля реєстрації зображень.