Out Spotlight LXVIII

Today's Out Spotlight is Dr. James B. Pollack.


Pollack was an American astrophysicist who worked for NASA's Ames Research Center. He was a world-renowned expert in the study of planetary atmospheres and particulates. It was his work that led to many advances in our understanding of the solar system.

Born on July 9,1938, Pollack was brought up in Woodmere, Long Island by a family that was in the women's garment business in New York. He was a high school valedictorian and graduated from Princeton University in 1960. He received his master's in nuclear physics at University of California, Berkeley in 1962 and his Ph.D from Harvard in 1965, where he was a student of the famous astronomer Carl Sagan. He later became a colleague of Sagan's.

He was openly gay. Dorion Sagan told how his father, Carl, came to the defense of Pollack's lover in a problem with obtaining treatment at the university health service emergency room.



Pollack specialized in atmospheric science, especially the atmospheres of Mars and Venus. He investigated the possibility of terraforming Mars, the extinction of the dinosaurs and the possibility of nuclear winter since the 1980s with Christopher McKay and Sagan. He and Sagan correctly postulated that the seasonal color variations on Mars were caused by wind storms and dust, rather than plant life. The work of Pollack et al. (1996) on the formation of giant planets ("core accretion paradigm") is seen today as the standard model. Pollack also discovered the first real evidence that the clouds of Venus are composed of sulphuric acid. He also explained the reason for the paradox that Saturn's rings showed low microwave emissivity but high radar reflectivity.

He explored the weather on Mars using data from the Mariner 9 spacecraft and the Viking mission. On this he based ground-breaking computer simulations of winds, storms, and the general climate on that planet. An overview of Pollack's scientific career was given in the memorial talk "James B. Pollack: A Pioneer in Stardust to Planetesimals Research" held at a Astronomical Society of the Pacific 1996 symposium.

He was one of five scientists, including Sagan, who introduced the term "nuclear winter" and, with a 1983 article, ignited a bitter dispute among scientists over whether a nuclear war would be likely to result in a catastrophic global chilling.

He was a recipient of the Gerard P. Kuiper Prize in 1989 for outstanding lifetime achievement in the field of planetary science.

He participated in every major NASA flight mission since Apollo until his death in 1994 from a rare form of spinal cancer.


A crater on Mars was named in his honor in 1997.