Jacobson Receives 2017 Ronald Greeley Early Career Award in Planetary Science

Seth A. Jacobson will receive the 2017 Ronald Greeley Early Career Award in Planetary Science at the 2017 American Geophysical Union Fall Meeting, to be held 11–15 December in New Orleans, La. The award recognizes “significant early career contributions to planetary science.”



The Ronald Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley award winner is Seth Jacobson, an assistant professor at Northwestern University.

Seth received his Ph.D. in astrophysical and planetary sciences from the University of Colorado Boulder in 2012 for work in asteroid dynamics including the evolution and formation of binary asteroids. His work on rotational fission of small bodies explains many of the observed dynamical properties and classes of near-Earth asteroids.

In his postdoctoral work at Nice Observatory, Seth has focused on major problems in terrestrial planet formation. By combining N-body simulations and geochemical and geophysical observations, Seth has made important contributions to our general understanding of the formation of the inner solar system and the Earth–Moon system. By combining observations of siderophile elements in Earth’s mantle with planet accretion models, Seth proposed a “cosmic clock” that relates the timescale for planet growth to the amount of residual primitive material and used it to constrain the age of the Moon-forming giant impact. Seth’s work on understanding rocky planet accretion and differentiation as concurrent processes sheds light on the differences between Venus and Earth, including Venus’s lack of a magnetic field.

In the words of a senior colleague, Seth is a “volcano of ideas.” Seth’s dynamism, curiosity, and creativity have established him as a young leader in planet formation research. The planetary science community congratulates Seth Jacobson for his outstanding early-career achievements.

—Sarah T. Stewart, University of California, Davis


It’s an honor to be selected by the Planetary Sciences section of AGU for the Ronald Greeley Early Career Award. I appreciate the recognition from the awarding committee and those who nominated me. One of the most influential undergraduate courses in my career was built around Ron’s book Planetary Surfaces and a field trip to look at terrestrial analogues in northern Arizona.

Throughout my education and my nascent career, the planetary science community has always been welcoming and encouraging to me. From far above Cayuga’s waters to the Flatirons, the Côte d’Azur, and now the shores of Lake Michigan, I have found inspiring colleagues willing to share their success with me, as well as lasting friendships. Particularly, I am thankful to planetary science for introducing me to Patrick, Catherine, Briony, Jay, Toshi, Christine, Robbie, Paul, Erik, Matija, Aurélien, Bert, Josef, Michiel, Federica, and Steve. I am also especially grateful to my advisors over the years: Jean-Luc, Dan, Dave, and Morby, as well as our colleagues at Cornell, Colorado, Bayreuth, and Nice Observatory.

I would like to dedicate this award to my wife, who always impresses me by her ability to find success in adversity and face changes bravely. I am also grateful to my family for their support of my career.

As I advance in my career, I plan to honor Ron’s legacy with a commitment to mentorship and service to the planetary science community. I will work to make the field of planetary science as welcoming and encouraging to everyone as it has been to me.

—Seth A. Jacobson, Northwestern University, Evanston, Ill.