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Using NASA’s spacecraft New Horizons, a lot of valuable information on the physical characteristics of the Pluto system was received. In particular: the sizes of the main bodies. There were hopes for determining the polar and equatorial oblateness of the figures of Pluto and Charon, and the second harmonic of their gravitational potential. However, the accuracy of the devices was not sufficient to determine these values: the errors of the measurements exceeded them. In this paper we show theoretical estimates of the oblateness, and the second and the fourth zonal harmonics under the assumption that the figures of Pluto and Charon are in hydrostatic equilibrium and are not subject to the action of external forces. It turned out that with all plausible assumptions about the internal structure of bodies, these quantities are of the order of 10−4. For the successful assignment of oblateness and nonsphericity of the gravitational field of bodies the devices must have the appropriate accuracy. In the future, we will take into account the interaction of Pluto and Charon, and the influence of the Sun and other celestial bodies. Most likely, the order of the quantities considered will not change. С борта космического аппарата NASA “New Horizons” получено много ценной информации о физических характеристиках системы Плутона. В частности, уточнены размеры главных тел. Возлагались надежды на определение полярного и экваториального сжатия фигур Плутона и Харона и второй гармоники их гравитационного потенциала. Однако точности приборов не хватило для определения этих величин: погрешности измерений их превосходили. Здесь мы даем теоретические оценки сжатия, второй и четвертой зональной гармоники в предположении, что фигуры Плутона и Харона находятся в гидростатическом равновесии и не подвержены действию внешних сил. Оказалось, что при всех правдоподобных предположениях о внутреннем строении тел указанные величины имеют порядок 10−4. Для успешного определения сжатия и несферичности гравитационного поля тел приборы должны иметь соответствующую точность. В дальнейшем мы предполагаем учесть взаимодействие Плутона и Харона и действие Солнца и других небесных тел. Скорее всего, порядок рассмотренных величин не изменится. Авторы благодарны В. Ш. Шайдулину за полезные замечания. Работа выполнена с использованием оборудования Вычислительного центра научного парка СПбГУ при финансовой поддержке РФФИ, грант 18–02–00552, (исследование фигур Ляпунова; М. А. Боруха, Б. Б. Эскин) и при финансовой поддержке РНФ, грант 18-12-00050 (исследование фигур Гюйгенса-Роша и гармоник гравитационного потенциала; К. В. Холшевников).

Veronica scutellata L. occurs in moist and wet habitats, such as ponds, marshes and other wetlands. This study was conducted on this species to examine its mineral element uptake status in terms of interactions between soil and plant. Experimental materials were taken from the Southern coast of Black Sea at coordinates 40°36'N and 31°16'E at an altitude of 1400 m above sea level from Bolu - Turkey; using standard methods and plant (root, stem and leaf parts) and soil mineral element measurements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) were done. During the study, ICP-OES was employed for the measurement of mineral elements. It was observed that considerable amounts of B, Ca, K, Mg, Mn, Na and Zn are accumulated by the plant., Veronica scutellata L. wujud di habitat lembab dan basah seperti kolam, rawa dan tanah bencah lain. Kajian dijalankan ke atas spesies ini untuk meneliti status pengambilan unsur mineral daripada segi saling tindakan antara tanih dan tumbuhan. Bahan percubaan telah diambil dari Pantai Timur Laut Hitam pada koordinat 40º36’U dan 31º16’T pada altitud 1400 m atas paras laut dari Bolu, Turki dengan menggunakan kaedah piawai dan tumbuhan (bahagian akar, batang dan daun) dan pengukuran unsur mineral tanih (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, Ni dan Zn) telah dilakukan. Semasa kajian, ICP-OES telah digunakan bagi pengukuran unsur mineral. Telah diperhatikan bahawa sejumlah amaun B, Ca, K, Mg, Mn, Na dan Zn telah terkumpul oleh tumbuhan.

Isoetes genus is commonly known as the "quillworts" and considered to be "fern allies". There are about 200-250 species, with a cosmopolitan distribution but often scarce to rare. Isoetes genus members often grow in extremely sensitive aquatic environments such as temporary ponds, streams and lakes. They are therefore good indicators of environmental quality. Isoetes anatolica Prada & Rolleri is an endemic plant grows on calcareous sediment/soil on the edges of seasonal ponds located in a mountainous area near the southern coast of the Black Sea at 1400 m above sea level at Bolu, Turkey. In this study, mineral element uptake statuses of I. anatolica populations were studied on the background of plant-sediment/soil-water interactions. The study materials were collected from the place where this narrow endemic species only lives in the world (Abant Region, Bolu/Turkey) by using standard methods and plant and sediment/soil mineral element measurements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) were done. ICP-OES was employed for the measurements during the study. Interrelations between mineral element contents in the sediment/soil, water and plant were discussed. The data revealed that I. anatolica is capable of accumulating considerable amounts of certain mineral elements (B, Ca, Mn and Na)., Marmara University, Commission of Scientific Research Project (FEN-D-040712-0291)