Steven Soter is an astrophysicist currently holding the positions of scientist-in-residence for

New York University New York University (NYU) is a private university, private research university in New York City, New York, United States. Chartered in 1831 by the New York State Legislature, NYU was founded in 1832 by Albert Gallatin as a Nondenominational ...

's Environmental Studies Program and of Research Associate for the Department of Astrophysics at the

American Museum of Natural History The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interconn ...

. He is a proponent of the

International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

's definition of planet.

Education

Soter received his

bachelor's degree A bachelor's degree (from Medieval Latin ''baccalaureus'') or baccalaureate (from Modern Latin ''baccalaureatus'') is an undergraduate degree awarded by colleges and universities upon completion of a course of study lasting three to six years ...

in astronomy and physics from

UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California, United States. Its academic roots were established in 1881 as a normal school then known as the southern branch of the C ...

in 1965 (advisors George Abell and Peter Goldreich) and his doctorate in astronomy from

Cornell University Cornell University is a Private university, private Ivy League research university based in Ithaca, New York, United States. The university was co-founded by American philanthropist Ezra Cornell and historian and educator Andrew Dickson W ...

in 1971 (advisors Thomas Gold,

Carl Sagan Carl Edward Sagan (; ; November 9, 1934December 20, 1996) was an American astronomer, planetary scientist and science communicator. His best known scientific contribution is his research on the possibility of extraterrestrial life, including e ...

, and Joseph Burns).

Career in astrophysics

In 1974, Soter suggested that dust produced by meteoritic bombardment of Saturn's moon Phoebe might orbit the planet until colliding with Saturn's moon Iapetus and be responsible for the unique dark-bright dichotomy of the latter. Although not the unique cause, dust originating from

Saturn Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 tim ...

's irregular satellites was later found in data from the Cassini spacecraft to indeed play a crucial role in the coloration of Iapetus. The discovery of Saturn's " Phoebe ring" in 2009 further strengthened the probability that this process first described by Soter plays a significant role in shaping Iapetus's appearance. In 1977-1979, Soter co-wrote, along with Carl Sagan and Ann Druyan, Carl Sagan's monumental 1980 astronomy documentary series ''

Cosmos The cosmos (, ; ) is an alternative name for the universe or its nature or order. Usage of the word ''cosmos'' implies viewing the universe as a complex and orderly system or entity. The cosmos is studied in cosmologya broad discipline covering ...

''. Since then, he has also acted as advisor on a number of science documentaries, such as the IMAX films '' Blue Planet'' and '' Cosmic Voyage''. In 1997, Soter took a position at the

's Hayden Planetarium, and eventually progressed to the position of research associate. He also made significant contributions to research related to the ancient Greek city Helike. In 2007, after the IAU voted on a definition of planet, Soter published an article in ''

Scientific American ''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it, with more than 150 Nobel Pri ...

'' in which he outlined a mathematical formulation, the "planetary discriminant," to describe how the IAU's requirement that a planet must have " cleared its neighborhood" of other objects might be applied in practice. He had already written a more technical article on the same subject in 2006, submitted to ''The Astronomical Journal'' before the IAU resolution. In 2014, he partnered with Druyan again to co-write a new television miniseries, '' Cosmos: A Spacetime Odyssey'', hosted by his AMNH colleague Neil deGrasse Tyson.

References

External links

Information on Steven Soter
at

website * 1943 births Living people Scientists from Los Angeles Cornell University alumni University of California, Los Angeles alumni People associated with the American Museum of Natural History {{US-physicist-stub