Iosif Shklovsky - Research

Research

He specialized in theoretical astrophysics and radio astronomy, as well as the Sun's corona, supernovae, and cosmic rays and their origins. He showed, in 1946, that the radio-wave radiation from the Sun emanates from the ionized layers of its corona, and he developed a mathematical method for discriminating between thermal and nonthermal radio waves in the Milky Way. He is noted especially for his suggestion that the radiation from the Crab Nebula is due to synchrotron radiation, in which unusually energetic electrons twist through magnetic fields at speeds close to that of light. Shklovsky proposed that cosmic rays from supernova explosions within 300 light years of the sun could have been responsible for some of the mass extinctions of life on earth.

In 1959 Shklovsky examined the orbital motion of Mars's inner satellite Phobos. He concluded that its orbit was decaying, and noted that if this decay was attributed to friction with the Martian atmosphere, then the satellite must have an exceptionally low density. In this context he voiced a suggestion that Phobos might be hollow, and possibly of artificial origin. This interpretation has since been refuted by more detailed study, but the apparent suggestion of extraterrestrial involvement caught the public imagination, though there is some disagreement as to how seriously Shklovsky intended the idea to be taken. However, Shklovsky and Carl Sagan argued for serious consideration of "paleocontact" with extraterrestrials in the early historical era, and for examination of myths and religious lore for evidence of such contact.

His 1962 book, Вселенная, жизнь, разум (“Universe, Life, Intelligence”), was expanded upon and reissued in 1966 with American astronomer Carl Sagan as co-author under the title “Intelligent Life in the Universe” (1966). This was the first comprehensive discussion of this field. Discussing the biological as well as astronomical issues of the subject, its unique format, alternating paragraphs written by Shklovsky and Sagan, demonstrated the deep mutual regard between the two and allowed them to express their views without compromise.

In 1967, before the discovery of pulsars, Shklovsky examined the X-ray and optical observations of Scorpius X-1 and correctly concluded that the radiation comes from an accreting neutron star.