Born Tartu, (Estonia), 19 August 1883
Died Spas-Demensk near Smolensk, (Russia), 14 April 1942
Leonid Kulik was a leading Soviet meteoriticist who is best known for his investigations of the 1908 Tunguska, Siberia, impact site. His father was a physician. Kulik’s secondary education was completed in 1903 at the Gymnasium in the town of Troitsk, Orenburg Province, in the Ural Mountains, where he won a gold medal. He then pursued an education at the Institute of Forestry in Saint Petersburg until he was inducted into military service in 1904 and sent to Kazan on the Volga River. On his own initiative, he attended lectures at the Faculty of Physics and Mathematics at Kazan University. In 1910, Kulik was arrested for revolutionary activities but, after serving a short time in prison, was sent to the Ilmen region of the Urals. During the next 2 years (1911–1912), he was paroled to work in the Forestry Department on the condition of making frequent reports to the police chief in the town of Zlatoust. In 1912, Kulik married Lidiya Ivanovna; both later served on the scientific staff of the Mineralogical Museum of the Academy of Sciences in Saint Petersburg. In the course of his fieldwork, Kulik had the good fortune to meet and work with a leading scientist, Vladimir Ivanovich Vernadsky, who became known as the father of geochemistry in the USSR. With the outbreak of war, Kulik joined the army and served on the western front.
After the October 1917 Revolution, Kulik’s record of arrest under the Czarist regime redounded to his advantage. Early in 1918, he went to the Soviet Academy of Sciences in Petrograd and started working on meteorites. Later that same year, Kulik led an expedition, organized by the academy, to investigate the fall of a stony meteorite on 27 February 1918, near the town of Kashin, in the province of Tver, a short distance north of Moscow. He returned with a 122-kg specimen of the Glasatovo chondrite, named for the village where it fell.
In 1921, the Mineralogical Museum of the Academy of Sciences in Petrograd established a meteorite section with Vernadsky as director. Vernadsky assigned Kulik to lead a 2-year expedition to gather information on the fall of a giant meteorite witnessed in Siberia in June 1908. Reports in provincial newspapers had described a brilliant fireball, visible over a vast area, moving from approximately the south to the north, accompanied by deafening explosions and a great trembling of the ground when it struck the Earth. Using a railroad car designated for the purpose, Kulik visited many places in Siberia and gathered eyewitness accounts. One story implied that the meteorite had landed at Tomsk in western Siberia. Kulik found no meteorite at Tomsk, but learned that the fireball had passed over the Yenesei Province and landed somewhere near the mouth of the Podkamennaya Tunguska River, a site so remote that he could not visit it on that trip.
Throughout his travels, Kulik collected reports of numerous meteorite falls, and sometimes obtained specimens. He made special efforts to educate the people he met about meteorites, and enlisted many volunteers to serve as corresponding observers who would send reports back to the institute on a regular basis. During the 1920s, Kulik issued updated instructions to this network, which grew in membership and in the volume of reports and specimens that were returned to Petrograd each year.
In 1927, Kulik led the first of several expeditions to the Tunguska area to investigate the 1908 fall. From the remote fur-trading station of Vanovara in eastern Siberia, he traveled by horse and reindeer into the deep forest. Kulik was led by local guides, some of whom had witnessed the event at fairly close range. Even after 19 years, the destruction he encountered was awesome beyond all expectations. Kulik found that a vast area of the forest had been uprooted and flattened, with treetops fanning outward. Only on later expeditions did he determine that the fallen trees pointed radially away from the center of an explosion. The tree roots faced a swampy area of low mounds and peat bogs pocked with rounded holes, up to a few dozen meters across, that Kulik believed were the craters made by a swarm of impacting meteorites.
In 1928 and again in 1929/1930, Kulik led two more arduous expeditions to Tunguska in an effort to excavate the water-filled holes and recover the meteorites. He directed the draining and trenching of one large depression, and the boring with hand augers into others. Kulik also conducted geodetic and magnetic surveys of the entire area. But all to no avail; he found no meteorites in the ground or on the surface. However, photographs of the flattened forest, taken on his expeditions, caused a sensation at home and abroad.
Back in Petrograd, Kulik argued for an aerial survey of the Tunguska region. The first attempt, made in 1930, was postponed twice for logistical problems. Faced with delays, Kulik conducted other inquiries. In 1933, he investigated a shower of stony meteorites that occurred on 26 December at Pervomaiskii Poselok in the Vladimir Province of Russia. It was seen over such a wide area that Kulik determined the approximate site of the fall from the reports sent to the Meteorite Institute. He visited the area immediately and obtained about 16 kg of specimens from local citizens. Kulik did not find the strewn field right away, but used a theodolite to calculate the trajectory of the fireball. After the snow melted, he went directly to the strewn field, aided by a group of schoolboys, and collected 97 stones weighing a total of 50 kg. This was the first known instance in which an instrumental calculation revealed the site of a meteorite fall.
In 1937, during an attempted aerial survey of Tunguska, the plane crash-landed but with no harm done to Kulik or the other passengers. Finally, in 1938, the aerial survey successfully revealed that the uprooted trees lay in an elliptical area with a center of devastation some 12–15 km across in the northwestern portion of the ellipse. The total affected area was 250 km2. Kulik returned to the site in the following year to correlate the aerial photographs with geodetic stations he had set up in the region. Further studies, however, were prevented by the onset of World War II.
When Kulik investigated the Tunguska site, only a few scientists favored a meteorite impact as the origin of craters found on the Earth or Moon. However, Kulik’s summary of eyewitness accounts of the fireball, together with his photographs of the devastation at the site, provided clear evidence that a large extraterrestrial body had wreaked destruction on the Earth in historic times. This finding prompted many scientists to take a new look at the possibilities of meteorite impacts as geological processes.
Kulik found no crater and no meteorites at Tunguska because, like most scientists of the time, he did not understand the explosive potential of meteorites moving through the Earth’s atmosphere at cosmic velocities. Today, astronomers and meteoriticists agree that the incoming body exploded in the atmosphere over Tunguska without reaching the ground and without depositing any meteorite fragments. The remaining point of contention is whether that body was a fragment of a comet or a friable asteroid.
By the start of World War II, Kulik held the position of curator of meteorites at the Soviet Academy of Sciences, a well-earned appointment that recognized his leading role in promoting the growth and documentation of the Soviet Union’s collection of meteorites. He was the first person to serve as the scientific secretary of the Academy’s Committee on Meteorites, which was chaired by Vernadsky. Kulik retained his civilian status because of weak eyesight. Nonetheless, he voluntarily joined the so called minutemen and was captured by the German army and put into a camp. He wrote a series of letters describing his daily life in the camp, where he did some paramedical work. Kulik contracted typhus and died.