## Events |

## Born on October 17th:

**Edouard Albert ROCHE (1820 - 8.4.1883)**, a French astronomer and mathematician, best known for his work in the field of celestial mechanics. He studied (1849-51) the structure of liquid bodies of revolution, taking into account the effects of both internal and external forces. The result was the Roche Model, which describes well the density distribution in stars, as well as the behavior and interaction of close binary stars. For the first time, he gave a mathematical justification of the Laplace Nebular Hypothesis (1873), examined in detail the process of formation of planets, satellites, asteroids.

**Yakov Grigorievich USACHEV (1873 - 28.10.1941)**, a Russian and Soviet physicist, one of the founders of the science of metal cutting. He designed a number of instruments for conducting experiments in this area, including the original dynamometer for measuring the tangential forces on a turning tool and thermocouples for measuring the temperature of the working part of the tool. Subsequently, these devices were widely used in scientific activities. His scientific work “ Phenomena that occur during the cutting of metals” is one of the first studies in this scientific field in the world. He was awarded the Order of Lenin (1936).

**Gyö zo ZEMPLEN (1879 - 6.6.1916)**, a Hungarian physicist who worked in the field of hydrodynamics and kinetic theory of gases. Known primarily by the Zemplen theorem. He took an active part in the training of physics teachers and in the reform of the teaching of physics in Hungary. He also wrote a textbook on electrodynamics "Electricity and its practical application" (1910) and translated the books of Marie Curie on radioactivity, and in 1905 wrote his own book on this subject. In 1914 he became a secretary of the society for the physics and mathematics founded by Lorand Eötvös and the editor of his journal.

**Paul Isaac BERNAYS (1888 - 18.9.1977)**, a Swiss mathematician, known for his work in the field of mathematical logic, axiomatic set theory and philosophy of mathematics. In collaboration with David HILBERT, he published the fundamental joint monograph Foundations of Mathematics in two volumes. He also published a number of works on the axiomatics of set theory, becoming one of the authors of the “ axiomatics of von Neumann-Bernays-Gödel”

**Winnett BOYD (1916 - 30.1.2017)**, a Canadian engineer who developed the first Canadian Chinook jet engine, Orend's jet engine (which was the most powerful of the existing jet engines in 1949-1952) and the nuclear reactor in the Chalk River, Ontario. Boyd won numerous engineering awards, including the University of Toronto's Engineering Alumni Medal in 1948, becoming an Associate Fellow of the Canadian Aeronautical Institute in 1954, and certificate of recognition from the Corporation of Professional Engineers of Quebec in 1959.

**Isaac Markovich KHALATNIKOV (1919)**, a theoretical physicist, an academician (1984). A great influence was exerted on I. M. Khalatnikov by joint work with L. D. Landau (the most famous theory of superfluidity is Landau - Khalatnikov). An author of studies on the basis of quantum electrodynamics (together with A. A. Abrikosov and L. D. Landau). He also worked in the field of general theory of relativity and cosmology, where he worked on the well known so-called Belinsky – Khalatnikov – Lifshitz singularity. He was elected a foreign member of the Royal Society of London (1994).

**Vladimir Fedorovich UTKIN (1923 - 15.2.2000)**, a designer of rocket and space technology, the chief designer and chief of the Yuzhnoye Design Bureau (Dnepropetrovsk), an academician (1984), the twice Hero of Socialist Labor, the laureate of the Lenin Prize. An active participant in the field of international cooperation in the exploration and exploration of outer space. A significant event was the implementation of the extensive Intercosmos program, which was a significant contribution to the joint study of near-Earth space by scientists from different countries. In collaboration with French scientists, the Arcade project was carried out using the Orel satellite.