Gansky Alexey Pavlovich

(08.07(20.07).1870 - 11.08.1908)

 

Russian astronomer, surveyor and gravimetrists.

Born in s. Nikolaevka (Ganskoe) (now Odessa region), Ananyevsky district, Kherson province in the family. The Ghanaian family settled in Ukraine under Catherine II, when Stephen Hansky, who served as secretary to Richelieu, changed his land in Galicia for land in the Kherson province. Alexey Pavlovich’s father, Pavel Petrovich, was educated in France and worked as a manager of the Kherson Noble Bank.

After graduating from the Faculty of Physics and Mathematics of the Novorossiysk (Odessa) University, Hansky was left with him to prepare for a professorship. At that time, the Odessa Astronomical Observatory was headed by Professor A.K. Kononovich, an energetic, progressive scientist and a talented teacher who was one of the first in Russia to become involved in astrophysics. Under his leadership during the years 1894-1896. Hansky was mainly engaged in photographing the Sun to study sunspots. Using very modest tools (6.5-inch refractor), he managed to get great shots.

In May 1896, Academician O.A.  Backlund  - Director of the Main Astronomical Observatory of Russia in Pulkovo visited the Odessa Observatory. Soon Hansky arrived in Pulkovo for further improvement in astrophotography. In the summer of the same year, he was invited to a scientific expedition of the Pulkovo Observatory to observe a total solar eclipse on August 9 at Novaya Zemlya. This expedition was successful in all respects, excellent observational material was obtained. In addition, Aleksey Pavlovich collected photographs and sketches of total solar eclipses, obtained in different years by many astronomers. Based on the analysis of all the collected scientific material, he came to important conclusions about the dependence of the shape of the corona on the number of sunspots on the Sun. At the maximum of sunspots, the corona forms a continuous glow around the sun. With a minimum number of them, the corona is increasingly stretched along the solar equator, and its brilliance diminishes accordingly. Thus, Hansky discovered the change in the shape of the solar corona with the phase of the 11-year cycle of solar activity. His prediction of the shape of the corona for a total solar eclipse of 1900 was brilliantly confirmed later by many astronomers.

After completing work related to the expedition, in early 1897, Hansky left for Paris. He became a listener at Sorbonne's lectures on mathematics, physics and astronomy, and at the same time was engaged in photographing the Moon under the guidance of Levi at the Paris Observatory. Then he began working at the Medona Observatory, famous throughout the world for classical methods of photographing the Sun.

To solve the problems of astrophysics, physics of the Earth and meteorology, Ghanaian based his own money in 1893 founded an observatory on Mont Blanc. Work at this observatory was very difficult due to the difficulties of climbing and the climatic conditions at its summit.

With extreme persistence, Hansky overcame these difficulties. He made 9 ascents on Mont Blanc in different years and, being there for long periods of time, made the most valuable observations. On Janssen's instructions, he was studying the solar constant using the Andre Crova actinometer. Here on Mont Blanc, Hansky did a great job of finding methods for photographing the solar corona outside of eclipses. They also carried out observations of Venus, and made an estimate of the period of change in its brightness, made gravimetric measurements, which also refers to important results obtained on Mont Blanc. For selfless work and brilliant scientific results obtained on Mont Blanc, Hansky was awarded the Cavaliers Cross of the Order of the Legion of Honor .

Working in Paris, Hansky did not lose touch with his hometown and wrote letters to his friends in the astronomical circle. In response, they expressed “the hope that our Aleksey Pavlovich, in spite of his friendship with C. Flammarion, Jansen, Nansen and other stars of science and civilization, will not forget his long-term friends.

Two summers of 1899 and 1901 Hansky participated in the Russian-Swedish expedition on the degree measurement on Svalbard. Almost all trigonometric and astronomical definitions on the Russian part of the arc were carried out by Pulkovo astronomers headed by the director of the observatory O.A. Backlund. Hansky conducted the determination of gravity on these expeditions, that is, he was mainly engaged in gravimetry, but also worked as a surveyor, astronomer and photographer. For his work on the last expedition, he was awarded the Order of St. Anna of 3 degrees , as well as the Nicholas II Prize , awarded on behalf of the Russian Astronomical Society, in which he had been since 1896. Subsequently, in 1907, he will be elected vice-president of the Russian Astronomical Society.

The end of the 19th and the beginning of the 20th centuries was a time of searching for new ways, methods and technical capabilities in observational astronomy. The French scientists Janssen and Flammarion were enthusiastic astronomical observations from balloons, and they themselves more than once went up on “hot air balloons”. Ghanaian twice in Paris and once in St. Petersburg climbed on balloons for scientific purposes.

1900 he spent in Potsdam, where he worked in the astrophysical laboratory of Vogel, one of the founders of the spectral classification of stars. There he also mastered the Hartmann method of studying the telescope optics. At the same time, at the Potsdam Geodesic Institute, Hansky studied the methods that German scientists used in gravimetry.

In 1903, Hansky began his studies of solar granulation, which he continued during the last years of his life. Only three astronomers at the beginning of the 20th century, Zhansen, Ghana and Chevalier, achieved extraordinary art in taking pictures of the Sun, capturing the finest details of sunspots and granulation. The quality of the photographs of the Sun and the formations on it made by the Ghanaian were unsurpassed until 1959, when the Sun was photographed with telescopes raised in balloons into the stratosphere. The inability of other observers to repeat such high quality of the images led to the fact that some conclusions made by the Ghanaian in their images, for example, about the rate of disintegration of the granules, were questioned, but life put everything in its place.

On September 23, 1904, the founding congress of the International Union for the Study of the Sun was held in St. Louis (USA) under the chairmanship of J. Hale, who became its first president. The desire for cooperation was due to the practical importance of continuous and comprehensive study of the sun. The delegate was the director of the Pulkovo Observatory O.A. Backlund. As early as January 3, 1905, the Russian branch of this union was founded under the name of the Commission for the Study of the Sun, which was headed by A.A. Belopolsky. A.P. Hansky was elected secretary.  On the day of the creation of the Russian Branch, Gansky A.P. delivered a very important report in which he proposed the creation of a high-altitude solar observatory. Hansky was the first astronomer in Russia to realize the need to organize the Heliophysical Observatory in the south. He himself developed the project, calculated the estimates for the construction of the future observatory, and in his articles of that time noted the possibility of construction in the Crimea, in the Caucasus and even in the Pamirs.

In 1904, the Paris Academy of Sciences awarded A.P. Ghanaian medal to them. P.ZH.S. Jansen. In 1907, A.A. Belopolsky received such an award  - the second of the Russian astronomers.

In 1905,  Hansky was hired to work at the Pulkovo Observatory as an adjunct astronomer. In the same year, on August 30, the Pulkovo Observatory sent two expeditions to observe a total solar eclipse — to Spain under the leadership of the  Hansky and to Egypt under the supervision of Okulich. According to the results of this expedition, Hansky came to important conclusions about the dependence of the shape and direction of the rays of the solar corona on the shape and direction of the protuberances. Thus, once again, the interrelation of diverse physical phenomena occurring on the Sun was convincingly substantiated.

In May 1906, A.P. Gansky and G.A. Tihov appealed to the Academy of Sciences with a proposal to send an expedition to the Crimea to study the zodiacal light and study the quality of images. The scientific results of this trip are small, but the fact that in Simeiz Hansky accidentally saw the private observatory N.S. Maltsev was probably her biggest success. The history of how this observatory became the Simeiz branch of the Pulkovo Observatory is well known.

In the course of the last two years, Hansky made a whole series of observations of the surface of Jupiter. Here he was rendered a great service of his drawing ability. The results of these observations are not fully processed.

At the beginning of the summer of 1908, Hansky left Odessa for Simeiz to set up an observatory. After a month of active work on installing the Zeiss astrograph and receiving the first test shots, he tragically died while swimming in the sea: he hit his head on a stone, lost consciousness and drowned. He was buried at Polikurovsky cemetery in Yalta.

Glacier in the southeast of the Earth Olaf V, West Spitsbergen Islands. The coordinates are 78° 40'N  20° 30'E.

 

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