- Email: [email protected]
Boris Yuljevich Levin (1912–1989)
ICARUS 84, 277--279 (1990)
IN MEMORIAM
Boris Yuljevich Levin (1912-1989) On April 10, 1989, Boris Yuljevich Levin, a great authority in the field of meteoritic phenomena, meteor astronomy, and planetary cosmology, passed away. Boris Yuljevich was born into a family of intellectuals in Moscow during 1912. From childhood he was keen on astronomy and in 1927 he joined the Moscow Society of Amateur Astronomers (MSAA), which became the scientific cradle for many well-known Soviet astronomers. Among the members of MSAA, B. Yu. Levin proved to be a talented observer, being head of its planetary and lunar section for many years and its scientific leader later. During the total solar eclipse of June 19, 1936, B. Yu. Levin, then 24 years old and a member of the Sagarchinsk expedition, managed to take four photos of the solar corona on which coronal streamers could be observed out to distances of at least 10 solar radii (and even more for some individual streamers) by skillfully using light filters. Having graduated from Moscow University in 1937 with a concentration in astronomy, B. Yu. Levin worked during the pre-war years first at the Moscow's K. Libknecht Pedagogical Institute and then at the Schternberg State Astronomical Institute. After some valuable results from amateur observations and notes on astronomical news, his first scientific publications of importance date back to the late 1930s and early 1940s. They deal with an altitude analysis of meteor burning and extinction, and later on with the physical theory of meteors. It should be noted that in these years the young science of the physics of meteoritic phenomena was taking only its first steps. In 1923 F. Lindermann and J. Dobson were the first to attempt to create a physical theory of meteors. This attempt proved to be unsuccessful and was subjected to justified criticism by K. Sparrow and U. Fischer. It was only in 1937 that I. Hoppe and F. Whipple independently derived the two basic differential equations in the modern theory of meteors. During the same years E. Opik laid the foundation of the theory of meteor glow, heating, and ablation. It was the critical approach taken by Sparrow and Fischer to the theory by Lindermann and Dobson that had a great effect upon the style of research by Boris Yuljevich, who was true to it for the nearly half-century of his scientific activity: no results should be taken on trust; everything should be called in question and subjected to scientific criticism. This feature of his was sometimes painfully taken by other scientists whose feelings were hurt by Levin's criticism: thus, differences in scientific opinions developed into declining personal relations. Meanwhile B. Yu. Levin set himself the same high standards. More than once the errors he had made in his earlier publications were exposed by him, and each time exact references to those publications were given in order that his colleagues would not use results that were proven untrue. A series of papers by B. Yu. Levin on the physical theory of meteors was concluded in 1956 with publication of the monograph "Physical Theory of Mete277 0019-1035/90 $3.00
278
IN MEMORIAM: BORIS YULJEVICH LEVIN ors and the Meteoric Matter in the Solar System" (Academy of Sciences, Moscow, USSR, 1956), which contained a comprehensive analysis of the two most important problems in meteor physics and astronomy, as reflected by the title of the book. In the same year B. Yu. Levin successfully defended his thesis for a doctoral degree on the monograph's subject. The monograph by B. Yu. Levin played an important role in the development of the physics of meteoritic phenomena for the following 25 years in both Soviet and world science. In 1961 it was translated into German and published in the German Democratic Republic. Its lucidity of presentation, accuracy of analysis, and high methodological standards have made it an indispensable handbook for researchers of meteors even today. After publication of this monograph, B. Yu. Levin concentrated his attention on meteor fragmentation and its effect upon the photometric meteor curve. These questions were studied in a number of his works during 1961-1967, partly in collaboration with A. N. Simonenko. Without giving up his meteor studies in the mid-1940s, B. Yu. Levin joined Academician O. Yu. Schmidt in the development of his cosmogonic theory and started regular work at the USSR Academy of Science's Institute of Physics of the Earth (named after Schmidt since 1956) to become his closest collaborator. The erudition of B. Yu. Levin in the field of astronomy was a great benefit to solving numerous problems arising before O. Yu. Schmidt's team, which was later organized into the Section of the Evolution of the Earth and the Planets. After O. Yu. Schmidt's death in 1956, B. Yu. Levin led this Section and held this post for nearly a quarter of a century. Scientists such as V. S. Safronov, E. L. Ruskol, S. V. Maeva, S. V. Kozlovskaya, and others were formed and raised there. Among the general problems connected with the origin of the Earth and the planets, certain issues attracted the special attention of B. Yu. Levin. These "favorable" issues included, in particular, the internal structure of the terrestrial planets and their large satellites and the origin of the Moon. For many years B. Yu. Levin supported and extended the hypothesis by V. N. Lodochnikov, according to which the Earth had no iron core, but rather the sharp density contrast between the mantle and the core was explained by phase transitions in stony rocks. Later, this hypothesis was not confirmed; however, it encouraged research on planetary interiors. Boris Yuljevich attached much importance to the study of meteorites. He considered them to be a class of small bodies in the Solar System rather than mere samples of cosmic matter, which are capable, due to ample opportunities in laboratory research, of providing scientists with valuable information about their genesis and of throwing light on the solution of planetary cosmogonic problems. He gave much of his attention to the investigation of meteor orbits, in which he was engaged from the mid-1940s until the late 1970s (during the last years this work was a collaboration with A. N. Simonenko until her untimely death in June 1984). For his studies of meteors and meteorites as well as his research in the field of planetary cosmogony, B. Yu. Levin was awarded the Leonard medal by the Meteoritical Society in August 1984, being the second Soviet scientist honored with such a prize (E. L. Krinov was the first and, more recently, V. S. Safronov has become the third). Although seriously ill already, Boris Yuljevich responded to the proposal of the Meteoritical Society to write an invited paper for Meteoritics and prepared (in collaboration with V. A. Bronshten) "The Tunguska Event
IN MEMORIAM: BORIS YULJEVICH LEVIN and Meteors with Terminal Flares," published also in the Solar System Research Journal. It was his last scientific publication. B. Yu. Levin made valuable contributions to cometary physics as well. All experts in cometary astronomy know the Levin formula that determines a comet's brightness as a function of the comet-Sun distance. For many years B. Yu. Levin was a member of the IAU Working Group of Planetary System Nomenclature and made great contributions to the solution of many "delicate" problems connected with choosing and giving names to morphological features on the surfaces of celestial bodies. His intellect, his broad-mindedness, his professional approach to being an astronomer, and his immense scientific prestige were successfully brought into concord in this important activity. B. Yu. Levin was the author of 150 scientific papers as well as several monographs and popular-science pamphlets ("Origin of the Earth and Planets," "Meteorites," and others). A series of his papers deals with the history of astronomy (specifically, the history of the cosmogonic Laplace hypothesis). Boris Yuljevich Levin was the Editor-in-Chief of the journal Letters to the Soviet Astronomical Journal from its founding (1974) until his death. He edited many good books on astronomy. He was also an excellent lecturer, a skilled speaker who knew several languages well. His memory will live forever in the history of Soviet and world science. M. YA. MAROV Institute o f Applied Mathematics Moscow
V. A. BRONSHTEN Committee on Meteorites Moscow
279
IN MEMORIAM
Boris Yuljevich Levin (1912-1989) On April 10, 1989, Boris Yuljevich Levin, a great authority in the field of meteoritic phenomena, meteor astronomy, and planetary cosmology, passed away. Boris Yuljevich was born into a family of intellectuals in Moscow during 1912. From childhood he was keen on astronomy and in 1927 he joined the Moscow Society of Amateur Astronomers (MSAA), which became the scientific cradle for many well-known Soviet astronomers. Among the members of MSAA, B. Yu. Levin proved to be a talented observer, being head of its planetary and lunar section for many years and its scientific leader later. During the total solar eclipse of June 19, 1936, B. Yu. Levin, then 24 years old and a member of the Sagarchinsk expedition, managed to take four photos of the solar corona on which coronal streamers could be observed out to distances of at least 10 solar radii (and even more for some individual streamers) by skillfully using light filters. Having graduated from Moscow University in 1937 with a concentration in astronomy, B. Yu. Levin worked during the pre-war years first at the Moscow's K. Libknecht Pedagogical Institute and then at the Schternberg State Astronomical Institute. After some valuable results from amateur observations and notes on astronomical news, his first scientific publications of importance date back to the late 1930s and early 1940s. They deal with an altitude analysis of meteor burning and extinction, and later on with the physical theory of meteors. It should be noted that in these years the young science of the physics of meteoritic phenomena was taking only its first steps. In 1923 F. Lindermann and J. Dobson were the first to attempt to create a physical theory of meteors. This attempt proved to be unsuccessful and was subjected to justified criticism by K. Sparrow and U. Fischer. It was only in 1937 that I. Hoppe and F. Whipple independently derived the two basic differential equations in the modern theory of meteors. During the same years E. Opik laid the foundation of the theory of meteor glow, heating, and ablation. It was the critical approach taken by Sparrow and Fischer to the theory by Lindermann and Dobson that had a great effect upon the style of research by Boris Yuljevich, who was true to it for the nearly half-century of his scientific activity: no results should be taken on trust; everything should be called in question and subjected to scientific criticism. This feature of his was sometimes painfully taken by other scientists whose feelings were hurt by Levin's criticism: thus, differences in scientific opinions developed into declining personal relations. Meanwhile B. Yu. Levin set himself the same high standards. More than once the errors he had made in his earlier publications were exposed by him, and each time exact references to those publications were given in order that his colleagues would not use results that were proven untrue. A series of papers by B. Yu. Levin on the physical theory of meteors was concluded in 1956 with publication of the monograph "Physical Theory of Mete277 0019-1035/90 $3.00
278
IN MEMORIAM: BORIS YULJEVICH LEVIN ors and the Meteoric Matter in the Solar System" (Academy of Sciences, Moscow, USSR, 1956), which contained a comprehensive analysis of the two most important problems in meteor physics and astronomy, as reflected by the title of the book. In the same year B. Yu. Levin successfully defended his thesis for a doctoral degree on the monograph's subject. The monograph by B. Yu. Levin played an important role in the development of the physics of meteoritic phenomena for the following 25 years in both Soviet and world science. In 1961 it was translated into German and published in the German Democratic Republic. Its lucidity of presentation, accuracy of analysis, and high methodological standards have made it an indispensable handbook for researchers of meteors even today. After publication of this monograph, B. Yu. Levin concentrated his attention on meteor fragmentation and its effect upon the photometric meteor curve. These questions were studied in a number of his works during 1961-1967, partly in collaboration with A. N. Simonenko. Without giving up his meteor studies in the mid-1940s, B. Yu. Levin joined Academician O. Yu. Schmidt in the development of his cosmogonic theory and started regular work at the USSR Academy of Science's Institute of Physics of the Earth (named after Schmidt since 1956) to become his closest collaborator. The erudition of B. Yu. Levin in the field of astronomy was a great benefit to solving numerous problems arising before O. Yu. Schmidt's team, which was later organized into the Section of the Evolution of the Earth and the Planets. After O. Yu. Schmidt's death in 1956, B. Yu. Levin led this Section and held this post for nearly a quarter of a century. Scientists such as V. S. Safronov, E. L. Ruskol, S. V. Maeva, S. V. Kozlovskaya, and others were formed and raised there. Among the general problems connected with the origin of the Earth and the planets, certain issues attracted the special attention of B. Yu. Levin. These "favorable" issues included, in particular, the internal structure of the terrestrial planets and their large satellites and the origin of the Moon. For many years B. Yu. Levin supported and extended the hypothesis by V. N. Lodochnikov, according to which the Earth had no iron core, but rather the sharp density contrast between the mantle and the core was explained by phase transitions in stony rocks. Later, this hypothesis was not confirmed; however, it encouraged research on planetary interiors. Boris Yuljevich attached much importance to the study of meteorites. He considered them to be a class of small bodies in the Solar System rather than mere samples of cosmic matter, which are capable, due to ample opportunities in laboratory research, of providing scientists with valuable information about their genesis and of throwing light on the solution of planetary cosmogonic problems. He gave much of his attention to the investigation of meteor orbits, in which he was engaged from the mid-1940s until the late 1970s (during the last years this work was a collaboration with A. N. Simonenko until her untimely death in June 1984). For his studies of meteors and meteorites as well as his research in the field of planetary cosmogony, B. Yu. Levin was awarded the Leonard medal by the Meteoritical Society in August 1984, being the second Soviet scientist honored with such a prize (E. L. Krinov was the first and, more recently, V. S. Safronov has become the third). Although seriously ill already, Boris Yuljevich responded to the proposal of the Meteoritical Society to write an invited paper for Meteoritics and prepared (in collaboration with V. A. Bronshten) "The Tunguska Event
IN MEMORIAM: BORIS YULJEVICH LEVIN and Meteors with Terminal Flares," published also in the Solar System Research Journal. It was his last scientific publication. B. Yu. Levin made valuable contributions to cometary physics as well. All experts in cometary astronomy know the Levin formula that determines a comet's brightness as a function of the comet-Sun distance. For many years B. Yu. Levin was a member of the IAU Working Group of Planetary System Nomenclature and made great contributions to the solution of many "delicate" problems connected with choosing and giving names to morphological features on the surfaces of celestial bodies. His intellect, his broad-mindedness, his professional approach to being an astronomer, and his immense scientific prestige were successfully brought into concord in this important activity. B. Yu. Levin was the author of 150 scientific papers as well as several monographs and popular-science pamphlets ("Origin of the Earth and Planets," "Meteorites," and others). A series of his papers deals with the history of astronomy (specifically, the history of the cosmogonic Laplace hypothesis). Boris Yuljevich Levin was the Editor-in-Chief of the journal Letters to the Soviet Astronomical Journal from its founding (1974) until his death. He edited many good books on astronomy. He was also an excellent lecturer, a skilled speaker who knew several languages well. His memory will live forever in the history of Soviet and world science. M. YA. MAROV Institute o f Applied Mathematics Moscow
V. A. BRONSHTEN Committee on Meteorites Moscow
279